healthy eating 2011

8/11/2019 Healthy Eating 2011

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A Harvard Medical School Special Health Repor

Price: $26

Healthy EatingA guide to the new nutrition

In this report:

Diet and your health

Which fats are good?

Do you needvitamin pills?

SPECIAL BONUS SECTION

Healthy snacking

This Harvard Health Publication was prepared exclusively for Noe Gonzalez - Purchased at http://www.health.harvard.edu/


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HEALTHY EATING

SPECIAL HEALTH REPORT

Faculty Editor

Teresa Fung, Sc.D., R.D., L.D.N.

Adjunct Associate Professor,Harvard School of Public Health

Associate Professor of Nutrition, Simmons College

Writers

Sandra GordonSusan Gilbert

Editor, Special Health Reports

Kathleen Cahill Allison

Art Director

Heather Derocher

Production Editors

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Melissa Rico

Illustrators

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Scott Leighton

Published by Harvard Medical School

Anthony L. Komaroff, M.D., Editor in Chief

Edward Coburn, Publishing Director

Copyright 2011 by Harvard University. Written permission is

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ISBN 978-1-935555-57-5

The goal of materials provided by Harvard Health

Publications is to interpret medical information for the

general reader. This report is not intended as a substitute for

personal medical advice, which should be obtained directly

from a physician.

ContentsEating for health . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

The food pyramid . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

New Dietary Guidelines for Americans . . . . . . . . . . . . . . . . . . . 4

Foods with healthy fats, carbs, and proteins . . . . . . . . . . . 5

All about fat . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

What about carbohydrates? . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

Update on protein . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

Getting vitamins from food (not pills) . . . . . . . . . . . . . . . 15

Fruits and vegetables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

Colorful choices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

SPECIAL BONUS SECTION: Healthy snacking . . . . . . . . . 19

Foods to avoid . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

Added sugar . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

Dairy fat . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

Baked sweets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

White carbohydrates . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

Processed and high-fat meats . . . . . . . . . . . . . . . . . . . . . . . . 24

Sugary beverages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

Salt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

The food-health connection . . . . . . . . . . . . . . . . . . . . . . . 26

Hindering heart disease and stroke . . . . . . . . . . . . . . . . . . . . 27

Halting hypertension . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

Defeating diabetes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

Battling breast cancer. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

Controlling colorectal cancer . . . . . . . . . . . . . . . . . . . . . . . . . 33

Preventing prostate cancer . . . . . . . . . . . . . . . . . . . . . . . . . . 35Beating bone loss . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36

Banishing birth defects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

Eradicating eye disease . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38

Discouraging diverticular disease . . . . . . . . . . . . . . . . . . . . . 38

Arresting Alzheimers disease . . . . . . . . . . . . . . . . . . . . . . . . 39

How safe is your food? . . . . . . . . . . . . . . . . . . . . . . . . . . . 40

The biggest threat: Contamination . . . . . . . . . . . . . . . . . . . . . 40

Handling food safely . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41

What about pesticides? . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42

Additives and your health . . . . . . . . . . . . . . . . . . . . . . . . . . . 42Other food safety issues . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43

Shopping for food . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45

Reading a food label . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45

Choosing meat and fish . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45

Buying grains and beans . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46

Shopping for fruits and vegetables . . . . . . . . . . . . . . . . . . . . . 46

Browsing the dairy case . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47

Eating out . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47

Resources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48

Glossary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49This Harvard Health Publication was prepared exclusively for Noe Gonzalez - Purchased at http://www.health.harvard.edu/


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Harvard Health Publications | Harvard Medical School | 10 Shattuck Street, Second Floor | Boston, MA 02115

Dear Reader,

Healthy eating is easier than ever. ats because we know so much more about what a

healthy diet looks like than we did even five years ago. Choosing healthy foods based on good

science remains the best known way to reduce your chances of developing heart disease and

diabetes and to help ward off hypertension, osteoporosis, and some forms of cancer.

Weve known for many years that certain foods promote good healthespecially fruits,

vegetables, some oils and fats, and whole grains. But the latest nutritional science shows that

there is not a single healthy diet. Instead, there are many patterns of eating around the

world that sustain good health. ey share these things in common: lots of fruits, vegetables,

and whole grains; healthy fats from fish and plant sources; low amounts of salt; and few addedsugars or solid fats. A healthy eating pattern also includes enough energy (calories) to fuel the

body, but not so much as to cause weight gain.

e U.S. Department of Agriculture (USDA) and the Department of Health and Human

Services (HHS) have jointly released the new Dietary Guidelines for Americans. ese

new guidelines emphasize lowering calorie consumption and increasing physical activity

to control the increasing prevalence of obesity, which contributes to heart disease, stroke,

diabetes, and some cancers. e guidelines, described in this report, urge people to choose

nutrient-dense foods, such as vegetables, and to avoid foods with empty calories, such as

sugary sweets and refined white carbohydrates.

As a nutrition researcher and an ordinary citizen, Im convinced that eating more whole

foodsunprocessed foods with few ingredients listed on the label, if the product has a label

at allisnt all that difficult. I know resourceful people with full-time jobs and families who,

for example, make their own organic yogurt because they got tired of paying the high prices

at the supermarket. It takes a little organizing to have the ingredients on hand and the right

equipment, but actually putting it all together takes just minutes. ats what this report will

help you discoverthat healthy eating is easier than you think. ere are many ways to get

away from factory-processed foods laden with fat, sugar, and salt.

is report provides the information you need to make the link between food and health.

And it will guide you in making healthy choices whether at home or on the road. Bon apptit!

Sincerely,

Teresa Fung, Sc.D., R.D., L.D.N.

Faculty Editor



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2 Healthy Eating www.hea l th .ha rva rd .edu

Not long ago, a healthy diet could be summed up

in two simple concepts. One: maintain a balanced

diet of proteins, carbohydrates, and fats. Two: get the

recommended amounts of vitamins and minerals.

Cover these bases, and youd have enough energy to

power your bodys cells and enough nutrients to pre-

vent deficiency diseases.

e basic notions of a healthy diet remain the

same, but science has expanded on them. Everyone

needs a mix of proteins, carbohydrates, and fats, plus

enough vitamins and minerals, but we now know that

some of the choices within these categories are bet-

ter than others. ere are good fats, which promote

health, and bad fats, which increase your risk of ill-

ness. e same is true for carbohydrates and possibly

for proteins. Regarding vitamins and minerals, the

latest thinking goes beyond diseases caused by defi-

ciency and now includes a knowledge of how these

substances affect our healthfrom bone strength to

birth defects, and from heart health to hypertension.

e form food comes in is also important. e

healthiest foods are those that have undergone as lit-

tle processing as possible, like those made from whole

grains that come with their natural fiber and nutrients,

rather than products made from white flourwhich

is stripped of these beneficial componentsand then

saturated with added salt, sugar, and fat. Although

many processed foods are fortified with vitamins,

the processing first removes their natural complement

of nutrients and fiber. ose naturally occurring com-

binations are what the human body has evolved to

thrive on over thousands of years. Foods reformulated

in factories cant begin to replicate the intricate nutri-

ent combinations that nature itself has devised.

e sad fact is that processed foods such as chips,

cookies, processed cheeses and meats, sodas, and

Eating for health

The widest section at the bottom of thispyramid is for things that are most impor-

tant. The top is for foods to be eaten only

sparingly, if at all. Begin at the bottom

with daily exercise and weight control. On

the next step up are the healthiest foods:

vegetables and fruits, healthy fats and oils,

and whole grains. These should make up

the bulk of your diet. Work your way up the

pyramid until, at the top, youll find foods

such as red meat, butter, and white starches

that you should eat sparingly, if at all.

Figure 1 The Healthy Eating Pyramid

Adapted from Eat, Drink, and Be Healthy:

The Harvard Medical School Guide to Healthy

Eating, by Walter Willett, M.D.

OPTIONAL:ALCOHOL IN MODERATION(Not for everyone)

DAILY MULTIVITAMINPLUS EXTRA VITAMIN D(For most people)

USE SPARINGLY: RED MEAT & BUTTER

REFINED GRAINS: WHITE RICE,

BREAD, PASTA, POTATOES

SUGARY DRINKS & SWEETS

SALT

DAIRY (1-2 servings a day)ORVITAMIN D/CALCIUM SUPPLEMENTS

FISH, POULTRY & EGGSNUTS, SEEDS, BEANS & TOFU

HEALTHY FATS & OILSFRUITS & VEGETABLES

DAILY EXERCISE & WEIGHT CONTROL

WHOLE GRAINS:

BROWN RICE, OATS, 100% WHOLE GRAIN

BREAD, WHOLE WHEAT PASTA & CEREAL

HEALTHY FATS & OILS

OLIVE, CANOLA, SOY,

SUNFLOWER, PEANU

OTHER VEGETABLE O

TRANS-FREE MARGA



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www.hea l th .ha rva rd .edu Healthy Eating 3

energy drinks remain top sources of mostly empty

calories for adults and children in the United States. In

the typical American diet, 35% of our total daily calo-

ries come from foods high in saturated (solid) fat and

added sugar, dubbed SoFAS by the USDA. ats high.

e USDA recommends that we get no more than 5%

to 15% of our total daily calories from SoFAS, with the

rest of our caloriesat least 85%from nutrient-dense,

minimally processed foods, such as whole grains, fruits

and vegetables, lean protein, and low-fat dairy products.

Beyond these basics of good nutritiongetting

a variety of nutrients from whole foods and limiting

salt, added sugar, and solid fatsit pays to become a

more adventurous eater. You can, for example, move

beyond foods made with wheat flour to other inter-

esting grains like quinoa, buckwheat, barley, and even

corn meal. If youre not sure how to cook with them,

the recipes on the packaging can help. Explore the

produce department as well, or try something differ-

ent when eating out. By expanding your palate, youll

cast a wide net and consume a broader range of nutri-

ents within your daily calorie budget that can help you

put up a more powerful food fight against disease.

The food pyramidIts a clever idea: organize foods into a pyramid with

the healthy foods at the wide bottom, to indicate

these should form the foundation of the diet, and put

unhealthy foods at the narrow top, to suggest you

should eat only small amounts. e USDA developed

its first food pyramid in 1992, and chances are its still

hanging in many classrooms and doctors offices around

the country. But nutrition information has changed a

great deal since then. In addition to the USDAs most

recent food pyramid, other experts, including those at

Harvard, have come up with their own food pyramids.

Harvards Healthy Eating Pyramid

In the Harvard pyramid, the widest sections toward

the bottom are for healthy things. e narrow top sec-

tion is for foods that should be eaten only occasion-

ally, if at all (see Figure 1). Harvard nutrition experts

point out that we now know that most fats from plants

and fish (unsaturated fats) are good for you, while

those from animals (saturated fats) and in many pro-

cessed foods (trans fats) are unhealthy. So sources of

these different types of fat are listed separately on the

pyramid according to their health benefits: healthy

fats near the bottom, unhealthy fats at the narrow top.

Look at the Healthy Eating Pyramid and youll see

that the largest part, the foundation, consists of daily

exercise and weight control. Although good food choices

will improve the health of overweight and obese people,

to be truly healthy its important to maintain a normal

weight and stay physically active. Physical activity and

weight control help prevent several serious illnesses.

e next level includes foods with good fats

and good carbohydrates. is level tells you that the

most important foods to eat are fruits and vegetables,

whole-grain foods (good carbohydrates), and plant

oils (good fats).

Next come nuts, seeds, and legumes. e Healthy

Eating Pyramid places nuts and legumes in their own

category instead of lumping them with meat and fish to

form one protein category. is reflects findings that

some forms of protein are healthier than others (see

Update on protein, page 12). Fish, poultry, and eggs

are on the same level. Next are dairy products. At the

very top are the foods you should eat least frequently:

refined starches and sweets (bad carbohydrates) and

red meat (particularly processed meat) and bad fats,

including saturated fats from animal products like but-

ter and trans fats found in many processed foods.

In doing the research for the Healthy Eating Pyr-

amid, Harvard scientists examined the diets of more

than 100,000 female nurses and male health profession-

als taking part in two long-term studies. ey found

that men whose diets most closely followed the Healthy

Eating Pyramid lowered their overall risk of major dis-

eases by 20% over eight to 12 years, compared with

men whose diets scored lowest on the healthy eating

recommendations. Women in the study who followed

the Healthy Eating Pyramid lowered their overall risk

by 11% compared with those who scored lowest. e

big wins came with cardiovascular disease. e top

nutritional scorers among both men and women cut

their risk by one-third or more. Healthy diet and life-

style lowered the risk of heart attacks even in people

who were taking medications for high cholesterol or



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high blood pressure, showing that good nutrition has

its own benefits independent of medications.

e Healthy Eating Pyramid isnt set in stone. As

nutrition researchers turn up more information over

time, it will change to reflect important new evidence.

And its not the only pyramid. If youd like to check

out some other healthy eating pyramids adapted to

Mediterranean, Latin American, Asian, and vegetarian

foods, go to the Web site for Oldways, the respected

nutrition think tank, at www.oldwayspt.org.

NEW DIETARY GUIDELINESFOR AMERICANSEvery five years, the government asks a committee to

review the latest nutritional science and create recom-

mendations for the public. e most recent guidelines

from U.S. Department of Agriculture and the Depart-

ment of Human Services have a new emphasis: weight

control. In previous years, the guidelines focused on

nutrients: What proportion of fats, proteins, and car-

bohydrates is optimum for health? Or, what amounts

of different vitamins and minerals do you need to

avoid deficiencies and ward off disease?

e slogan for the new guidelines is: Calories in,

calories out. Put another way: Americans should strive

to maintain a calorie balance, eating no more calories

than they burn each day. If you are overweight, the goal

is to eat fewer calories than you burn each day in order to

reach a healthy weight. Calorie control and daily physi-

cal activity are the cornerstones of the new guidelines.

Why the emphasis on weight control? e Dietary

Guidelines report explains it this way: Poor diet and

physical inactivity are the most important factors con-

tributing to an epidemic of overweight and obesity affect-

ing men, women, and children in all segments of our

society. Even in the absence of overweight, poor diet and

physical inactivity are associated with major causes of

morbidity and mortality in the United States. With this

in mind, the Dietary Guidelines include these recom-

mendations for foods to cut back and foods to increase:

Foods to reduce

Reduce daily sodium intake to less than 2,300 mil-

ligrams (mg) and further reduce intake to 1,500 mg

among persons who are 51 and older and those of

any age who are African American or have hyper-

tension, diabetes, or chronic kidney disease.

Consume less than 10% of calories from saturated

fatty acids by replacing them with monounsaturated

and polyunsaturated fatty acids.

Consume less than 300 mg per day of dietarycholesterol.

Keep trans fatty acid consumption as low as possible.

Reduce the intake of calories from solid fats and

added sugars.

Limit the consumption of foods that contain refined

grains, especially those with solid fats, added sugars,

and sodium.

If alcohol is consumed, it should be consumed in

moderationup to one drink per day for women

and two drinks per day for menand only by adultsof legal drinking age.

Foods and nutrients to increase

Strive to increase your intake of these foods while

staying within your calorie goals.

Eat a variety of fruits and vegetables, especially dark

green, red, and orange vegetables, fruits, and beans

and peas.

Consume at least half of all grains as whole grains.Increase whole-grain intake by replacing refined

grains with whole grains.

Increase intake of fat-free or low-fat milk and milk

products, such as milk, yogurt, cheese, or fortified

soy beverages.

Choose a variety of protein foods, which include sea-

food, lean meat and poultry, eggs, beans and peas,

soy products, and unsalted nuts and seeds.

Choose seafood in place of some meat and poultry.

Replace protein foods that are high in solid fats withproteins that are low in solid fats and calories.

Use healthy vegetable oils to replace solid fats

where possible.

Choose foods that provide more potassium, dietary

fiber, calcium, and vitamin D, which are nutrients of

concern in American diets. ese foods include vegeta-

bles, fruits, whole grains, and milk and milk products.



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How do you know the difference between a good fat

and a bad fat? e same question applies to car-

bohydrates and proteins. ese foods, known as mac-

ronutrients, are the basic categories of nutrients that

humans need. ey provide the body with energy, and

they enable the body to carry out many normal bio-

logical functions. A healthy diet consists of a mix of

foods from each of these three macronutrient catego-

ries, although not in equal amounts. e latest science

tells us that instead of focusing on individual nutri-

ents, its best to think about your overall dietary pat-

tern. Try for a mix of whole foods from nature, not

factory-made foods, with a variety of sources of fats,

carbs, and proteins.

ere is no one healthy diet, but many, from

around the world. One example of a healthy mix of

fats, carbohydrates, and proteins is the Mediterra-

nean diet; another is known as the DASH (Dietary

Approaches to Stop Hypertension) diet (see Eat-

ing plans for good health, page 29). It and variations

known as DASH-style diets are high in fruits and

vegetables and healthy plant oils.

A panel of U.S. and Canadian scientists backed by

the National Academy of Sciences Institute of Medi-

cine has set dietary reference intakes (DRIs) for mac-

ronutrients based on research on diet and health (see

How much of each? at right). e DRIs set forth the

range of macronutrients in a diet balanced to main-

tain a healthy weight and to prevent serious conditions

such as heart disease, cancer, hypertension, and diabe-

tes.e DRIs also provide guidelines for fiber (a form

of indigestible carbohydrate that serves several func-

tions in the body) and vitamins and minerals.

All about fatFat now makes up about one-third of the average

Americans diet. At one time, experts encouraged peo-

ple to eat less fat. ese days, experts are more con-

cerned about the type of fat you eat, especially for

heart health, thanks in part to decades of studies at

Harvard Medical School and the Harvard School of

Public Health. is change was further supported in

2006 when the Womens Health Initiative, a national

study of about 49,000 women, showed that a low-

fat diet didnt significantly reduce the womens risk

of heart disease, breast cancer, or colon cancer. As

it turns out, its the type of fat you eat, not the total

amount, that counts.

e body needs fat. Its a major energy source and

also helps you absorb certain vitamins and nutrients.

Certain fats from plant sources and fish turn out to

be the most beneficial. ese unsaturated fatswhich

come mainly in the form of vegetable oils, nuts, and

Foods with healthy fats, carbs, and proteins

How much of each?

Following are the dietary reference intakes (DRIs) for fats,carbohydrates, and proteinsthe amounts needed dailyto meet nutritional needs for adults while minimizing risk

for disease. But keep in mind that more important thanstrictly adhering to these percentages is making sure tochoose healthy sources for fats, carbohydrates, andproteins, as described in this report.

Fats:20% to 35% of daily calories (reduce saturatedand trans fats as much as possible while consuming anutritionally adequate diet).

Protein:10% to 35% of daily calories.

Carbohydrates:45% to 65% of daily calories (reduceconsumption of added sugar).

Fiber (indigestible carbohydrate):14 grams per every1,000 calories. Thats about 21 to 38 grams a day, basedon age and sex, as follows:

men ages 50 and younger: 38 grams/day

women ages 50 and younger: 25 grams/day

men over age 50: 30 grams/day

women over age 50: 21 grams/day.

Dietary Reference Intakes: The Essential Guide to Nutrient Requirements,

Institute of Medicine (National Academy of Sciences).



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whole grainsare good for you. ere are two types

of unsaturated fat: polyunsaturated fat and mono-

unsaturated fat. ese good fats can help lower LDL

(bad) cholesterol, prevent abnormal heart rhythms,

and prevent heart disease. (For more information on

fats and specific illnesses, see e food-health con-

nection, page 26.)

Only some fats are bad for you: trans fats (found

in some manufactured foods and margarines) and

some saturated fats (found mainly in meat and whole-

fat dairy foods). Bad fats boost your chances of devel-

oping heart disease by increasing blood levels of two

of its main risk factors, LDL cholesterol and triglycer-

ides. Trans fats also lower levels of protective HDL, the

good cholesterol.

e DRI for fat gives considerable leeway: 20%

to 35% of your daily calories can come from fat. is

means you can get up to 35% of your calories from fat

and still have a diet thats good for your heart, helps

reduce your risk of hypertension, and lets you main-

tain your weight or even lose weight. Even more may

be fine, so long as its mostly healthy fats from fish and

vegetables (see Eating plans for good health, page 29).

Although research results are conflicting, its best

to limit red meat, particularly processed meat, and

full-fat dairy products like butter, cheese, and ice

cream. Try to choose non-fat or low-fat dairy products

and lean cuts of meat, poultry, fish, soy, and beans. Pro-

cessed and cured meats are particularly linked to an

increased risk of cardiovascular disease. For trans fats,

there is no safe level, and the guidelines recommend

eating as little as possible.

Whats the difference between a good fat and a bad

fat? All fats have a similar chemical structure: a chain

of carbon atoms bonded to hydrogen atoms. What dif-

fers is the length and shape of their carbon chains and

the number of hydrogen atoms connected to the car-

bon atoms. Seemingly slight differences in structure

translate into crucial differences in the body.

Bad fat

e two forms of unhealthy fat, trans fats and satu-

rated fats, share a physical trait: theyre solid at room

temperature. ink of butter, margarine, shortening,

or the marbled fat in a steak. But bad fats abound in

some liquids, too, including whole milk, cream, and

palm and coconut oils. ese fats drive up your total

cholesterol, tipping the balance toward LDL choles-

terol, the destructive type that prompts blockages to

form in the coronary arteries, the hallmark of heart

disease. e expert panel of the National Cholesterol

Education Program recommends cutting back on

saturated and trans fats as a means of preventing and

controlling heart disease.Saturated fat.e word saturated here refers to

the number of hydrogen atoms in this type of fat. In

saturated fat, the chain of carbon atoms holds as many

hydrogen atoms as possible, making it literally satu-

rated with hydrogen atoms. Each carbon atom in the

chain is connected to the next by a single bond, leav-

ing the maximum number of bonding points available

to hold hydrogen. By contrast, in unsaturated fats, the

carbon atoms have fewer than the maximum number

of hydrogens.

Saturated fat, which is concentrated in full-fat

dairy products and meat, has received some posi-

tive publicity in the media lately. Maybe youve seen

reports that it doesnt cause heart disease aer all.

Unfortunately, many media stories oversimplified

the conclusions of the scientists who conducted a

21-study meta-analysis published in Te American

Journal of Clinical Nutrition in 2010.

e study really said that there was not enough

evidence to conclude that saturated fat increases the

risk of heart disease, but that replacing saturated fat

with polyunsaturated fat may indeed reduce risk of

heart disease.

Two other major studies in the same academic

journal narrowed the prescription slightly, concluding

that replacing saturated fat with polyunsaturated fats

like vegetable oils or high-fiber carbohydrates is the

best bet for reducing the risk of heart disease. All told, if

you are trying to reduce saturated fat, your best choice

is to replace it with polyunsaturated oils, like corn oil.

In regards to cholesterol, a diet high in saturated

fats boosts total cholesterol by elevating harmful

LDL. Like all dietary fat, saturated fat also raises the

protective HDL. But eating unsaturated fat is a bet-

ter choice because it lowers the bad cholesterol and

raises the good.



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Trans fats (partially hydrogenated oils).Trans fats are

rapidly fading from the scene, thanks to the govern-

ment requirement that they be listed on food labels.

Trans fats were created in the laboratory to provide

cheap alternatives to butter. Food chemists learned

how to solidify vegetable oil by heating it in the pres-

ence of hydrogen and a heavy-metal catalyst such as

palladium. e process, called hydrogenation, gives

the carbon atoms more hydrogen atoms to hold, mak-

ing polyunsaturated fat (a good fat) more like satu-

rated fat in structure. ats how solid vegetable fats

such as shortening and margarine came into being.

On food label ingredient lists, this manufactured sub-

stance is typically listed as partially hydrogenated oil.

Trans fats are even worse for you than saturated

fats. Not only do they increase your LDL cholesterol,

but they also reduce your beneficial HDL cholesterol.

e Institute of Medicine expert panel stated that trans

fats have no known health benefits and that there is no

safe level of consumption.

Since 2006, the FDA has required trans fat con-

tent to be listed as a separate line item on food labels.

As a result, the food industry has reduced trans fats in

many foods, and some local governments have banned

trans fats in restaurant foods. Happily, these mainly

man-made fats, which used to be in everything from

commercial cookies to fast-food fries, are now much

less prevalent. Harvard researchers and the Center for

Science in the Public Interest, a consumer advocacy

group, recently analyzed 83 reformulated supermarket

and restaurant foods and found that nearly all of them

were free or mostly free of trans fat, and that saturated

fat hadnt replaced it, yielding products and menu

items with a healthier balance of fats.

Be aware that although many labels now state

0 trans fat, manufacturers can still sneak them in.

According to the labeling law, if a product has no

more than half a gram of trans fat per serving, the

label can list it as having 0 grams of trans fat. By mak-

ing the serving size very small (two small cookies, for

example), the manufacturer may thus be able to label

a product as having 0 grams trans fat per serving. But

if you eat six cookies, you may have consumed nearly

3 grams of trans fat. Check the label for hydrogenated

oils and be wary of foods with small serving sizes.

And keep in mind that just because a cookie is listed

as having no trans fat, its still a cookie, which can be

loaded with saturated fat, sugar, and empty calories.

Good fat

Good fats come mainly from vegetable, nut, and fish

products. ey differ from bad fats by having fewer

hydrogen atoms bonded to their carbon chains. ey

are liquid, not solid, at room temperature. ere are

two broad categories of beneficial fats: polyunsatu-

rated and monounsaturated.Polyunsaturated fats.When you pour liquid cook-

ing oil into a pan, theres a good chance youre using

polyunsaturated fat. Corn oil, sunflower oil, and saf-

flower oil are common examples. (e exceptions

are sunflower and safflower oils labeled high-oleic,

which come from crops intentionally bred to produce

mostly monounsaturated fats.) Polyunsaturated fats

are essential fats. at means theyre required for nor-

mal body functions, but your body cant manufacture

them and so you must get them from food. Polyun-

saturated fats help build cell membranes, the exte-

rior casing of each cell, and the sheaths surrounding

nerves. eyre vital to blood clotting, muscle move-

ment, and inflammation. ey reduce LDL more than

other types of fats, improving your cholesterol profile.

Even better, they also lower triglycerides.

A polyunsaturated fat has two or more double

bonds in its carbon chain. ere are two types of

polyunsaturated fats: omega-3 (n-3) fatty acids and

omega-6 (n-6) fatty acids. (e numbers refer to the

distance between the end of a carbon chain and the

first double bond.) Both types offer health benefits.

Research has shown that omega-3s in dietary fish

and fish oil supplements help prevent and even treat

heart disease and stroke. e reasons are several: these

fats help reduce blood pressure, raise HDL, lower tri-

glycerides, andperhaps most importantlyprevent

lethal heart-rhythm disorders. Evidence also suggests

they may help reduce the need for corticosteroid medi-

cations in people with rheumatoid arthritis. Unfortu-

nately, most of the other studies linking omega-3s to

a wide range of other health improvements, including

reducing risk of dementia, are inconclusive, and some

of them have major flaws, according to a systematic



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review of the evidence by the Agency for Healthcare

Research and Quality.

Omega-3s come mainly from fish, but you can

also find them in flaxseeds, walnuts, canola oil,

and unhydrogenated soybean oil. Fatty fish such as

salmon, mackerel, and sardines are especially good

sources of omega-3s. e DRI for alpha-linolenic acid,

the omega-3 in vegetable oils, is 1.6 grams per day for

men and 1.1 for women.

Omega-6 fatty acids are even more protective

against heart disease. High levels of linoleic acid, an

omega-6, are in such vegetable oils as safflower, soy-

bean, sunflower, walnut, and corn oils. (Be aware,

however, that high-oleic safflower and sunflower

oils, oen used in chips, have much lower omega-3

and omega-6 content.) e DRI for linoleic acid is 17

grams per day for men ages 19 to 50 and 12 grams for

women in this age group. For adults ages 51 to 70, the

DRI is 14 grams for men and 11 grams for women.Monounsaturated fats.When you dip your bread in

olive oil at an Italian restaurant, youre getting mostly

monounsaturated fat. Unlike a polyunsaturated fat,

which has two or more double bonds of carbon atoms,

a monounsaturated fat has just one. e result is that

it has more hydrogen atoms than a polyunsaturated

fat, but fewer than a saturated fat. Although theres no

DRI for monounsaturated fats, the Institute of Medi-

cine recommends using them as much as possible

along with polyunsaturated fats to replace saturated

and trans fats. Good sources of monounsaturated fats

are olive oil, peanut oil, canola oil, avocados, and most

nuts, as well as high-oleic safflower and sunflower oils.

e discovery that monounsaturated fat could

be healthful came from the Seven Countries Study

during the 1960s. is study revealed that people in

Greece and other parts of the Mediterranean region

enjoyed both a low rate of heart disease and a high-fat

diet. e fat in their diet, however, was not the ani-

mal fat common in other countries with higher rates

of heart disease: it was olive oil, which has mainly

monounsaturated fat. is finding produced a surge

of interest in olive oil and the Mediterranean diet,

a style of eating regarded as a healthful choice today.

What about carbohydrates?Carbohydrates encompass a broad range of foods,

including table sugar, fruits and vegetables, and grains

such as rice and wheat. e DRI for carbohydrates is

45% to 65% of your daily calories. But, as the Healthy

Eating Pyramid shows, most of these carbohydrates

should come from whole-grain foods, vegetables, and

fruits. If most of the carbohydrates you eat are bad

carbohydrates (white bread, white potatoes, white

rice, and other refined starches or sugars found at the

top of the Healthy Eating Pyramid), you could end up

gaining weight and putting yourself at risk for disease.

e list of bad carbohydrates may come as a sur-

prise. Why point the finger at potatoes? eyre vege-

tables, aer all. Why are they in the same category as

sweets? To answer these questions, you have to con-

sider the glycemic index of a food.

e glycemic index reflects the spike in blood

sugar caused by eating a certain amount of a particu-

lar food compared with that of white bread or pure

sugar. In general, healthy carbohydrate foods have a

lower glycemic index than unhealthy ones. White

pasta has a higher glycemic index than whole-wheat

pasta because it raises blood sugar more than the same

amount of whole-wheat pasta.

You may also have heard the term glycemic load.

is is oen a more useful term because it describes

both the amount of carbohydrate in a serving of food

and how fast that amount will raise your blood sugar

level. e glycemic load is simply the foods glycemic

Building your plate

At mealtime, simplify the process of healthy eating bydividing your plate in half. Fill one half with vegetables.Divide the other half into two quarters, filling one quarterwith lean protein such as fish or skinless chicken. Fill theremaining quarter with whole grains such as brown rice,whole-wheat pasta, barley, or quinoa.

Keep portion sizes moderateto avoid weight gain.

Choose beverages with littleor no sugar.

Then, after you eat, go out fora walk.



12/53


index times the amount of carbohydrate in a serving.

For example, a big slice of white bread will spike the

blood sugar more than a little slice of the same white

bread. e glycemic index is the same for both pieces,

but the glycemic load is higher for the large piece. For

menu-planning purposes, the glycemic load is more

meaningful than the glycemic index because its based

on the portion size of a particular food eaten.

Foods with a high glycemic index are digested more

quickly than foods with a low glycemic index (see Table

1). Rapidly digested foods can be dangerous because

they flood your bloodstream with sugar all at once.

Sudden, high spikes of blood sugar trigger a gush of

insulin to clear the sugar from your blood. e problem

is that this quick surge of insulin can leave your blood

sugar too low aer just a few hours. When your blood

sugar is too low, you feel hungry; if its low soon aer a

meal, youre apt to overeat and possibly gain weight.

Another problem with a steady diet of high-

glycemic meals is that over many years, your bodys sys-

tem of responding to insulin could become impaired.

is is called insulin resistance. When your cells are less

responsive to insulin, the resulting overload of sugar in

your bloodstream forces the pancreas to produce more

insulin in an effort to move the sugar (glucose) from

the blood into the cells. is itself will further reduce

the response of muscles to insulin to take up sugar from

the blood. As this situation worsens, blood sugar rises

chronically to an abnormal level defined as type 2 dia-

betes. If the pancreas is forced into overdrive for a sus-

tained period, it may wear down and eventually lose

some of its ability to produce insulin, leading to insu-

lin deficiency and worsening of type 2 diabetes. Insu-

lin resistance can also cause other problems, including

heart disease and perhaps some cancers.

Good carbs, bad carbs

e high-carbohydrate foods that are good for you can

help protect against health problems in part because

they have a relatively low glycemic load. eyre

digested slowly, which means they cause a gradual

rise in blood sugar. How can you tell the difference?

Table 1 Choosing foods with a low glycemic index

LOW GLYCEMIC INDEX (BEST CHOICE) MODERATE GLYCEMIC INDEX HIGH GLYCEMIC INDEX

Vegetables

asparagus, avocado, broccoli, carrots, celery,chard, lettuce, mushrooms, okra, onion,peppers, spinach, tomatoes, zucchini

beets, butternut squash, green peas, parsnips,plantain, pumpkin, sweet potato

corn, French fries, potato, potato chips

Fruits

apples, berries, cantaloupe, cherries,grapefruit, grapes, kiwi, lemon, nectarines,oranges, peaches, pears, plums

applesauce, banana, dried fruit, mango,papaya, pineapple, watermelon

fruit juices and drinks

Nuts

almonds, cashews, peanut butter (no addedsugar), peanuts, pecans, pistachios, walnuts

peanut butter (with sugar)

Grains

steel-cut oats amaranth, barley, bread (whole-grain,minimally processed), breakfast cereal (high-fiber), brown rice (varies by type), buckwheat(kasha), bulgur, millet, pasta (not canned),quinoa, wheat berries, wild rice

Products made with highly processed whiteflour such as bagels, buns, corn bread, Englishmuffins, pita, breakfast cereals, couscous,crackers, pancakes, pasta (canned), popcorn,pretzels, rice cakes, stuffing, taco shells,tortillas, white rice

Dairy

cheese, milk, yogurt (no added sugar)

Source: Ending the Food Fight,by David Ludwig with Suzanne Rostler (Houghton Mifin, 2008). See www.glycemicindex.com to look up more foods.



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You can gauge whether a carbohydrate is good or bad

based on these characteristics:How heavily processed is the food?Some scientists

think that the glycemic load of the average Ameri-

can diet has increased because were eating greater

amounts of prepared foods that contain heavily pro-

cessed carbohydrates. One factor in a grain products

glycemic load is its degree of refinement. In general,

the smaller the pieces, the faster theyre digested.

is is one reason finely ground white wheat flour is

digested faster than coarsely ground (sometimes called

stone-ground) wheat flour. Its the same with steel-

cut oats compared with instant or quick oatmeal.

Processing also removes the fibrous casing from

grains. is casing is good for you because it slows

digestion and contains a host of nutrients that may

lower the risk of some diseases. Studies show that

whole-grain foods such as brown rice and barley,

which have their fibrous casing intact, are healthier

than the more heavily processed refined grains. In

results from two large ongoing studies, the Nurses

Health Study and the Health Professionals Follow-

up Study, people who ate the most whole grains (four

slices of whole-wheat bread daily) were less likely than

other people to develop type 2 diabetes, heart disease,

and several types of cancer, including cancer of the

mouth, stomach, colon, gallbladder, and ovary.Is it really whole grain?Not all foods in the gro-

cery store that claim to be whole grain really are.

Whole-wheat bread may include a lot of refined

white flour. Look for labels that say 100% whole

wheat (or oats or rye or another grain). Read the

ingredients list to make sure that the first ingredient

is a whole grain.

Some whole-grain foods can be easily spotted by

their color. Brown rice is a whole grain (its brown

because its casing is intact), but white rice isnt. But

color isnt always a good indicator because some

whole-grain products dont look the part. As youll

notice in restaurants advertising whole-wheat pizza

crust and on grocery store shelves, some whole-grain

breads and other items are now white. Whole-wheat

white bread may sound like an oxymoron, but its the

real deal. is new color trend is part of the increas-

Calories and teaspoons of sugar in 12 ounces of each beverage.

For more information, see the The Nutrition Source, www.hsph.harvard.edu/nutritionsource/healthy-drinks.

Figure 2How sweet is it?

Drink sparingly and infrequently

170 Calories

Cola

A better choice, but dont overdo itBest choice

NUMBEROFTEASPOONSOFSUGARPER12OZ.SERVING

200 Calories

Cranberryjuice cocktail

90 Calories

Sportsdrink

170 Calories

Orangejuice

15Calories

Seltzer with asplash of juice

15Calories

Coffee or tea witha sugar packet

0 Calories

Sugar-freenaturally

(water, teas,seltzer, etc)

12

11

10

9

8

7

6

5

4

3

2

1



14/53


ingly creative effort that food companies are making

to introduce whole-grain products into the grocery

carts of the white-bread-only consumer. To make

whole-grain bread white, manufacturers use an albino

variety of whole-wheat flour thats lower in gluten and

soer in texture. Because the flour isnt refined, its

technically a whole grain. However, its so new to the

market that its glycemic index is still unknown.How much fiber is in the food?Fiber is the indigest-

ible part of grains, vegetables, and fruits. Its delays the

time it takes for the food to be digested. Whole-grain

foods have more fiber than refined foods (see Fiber:

e workhorse, below).How much fat is in a meal or snack?Youll reduce

the spike in blood sugar from carbohydrates by com-

bining the food with protein or fats. Because fats take

longer to digest than carbohydrates, the more fat a

meal or snack has, the more slowly it will be digested

and, possibly, the less detrimental an effect it will have

on your blood sugar. Just make sure that the fat or pro-

tein is a healthful one. A handful of cashews or other

nuts is a better snack than a cookie made with butter

or trans fats.

Fiber: The workhorse

Fiber is a form of indigestible carbohydrate found

mainly in plant foods. Over the years, fiber has been

hailed as a potential weapon against cancer, high cho-

lesterol, and heart disease. Fibers vaunted health ben-

efits were diminished slightly by findings that it doesnt

prevent colon cancer or colon polyps (precursors of

colon cancer). Studies continue to be published, how-

ever, presenting a mixed picture. (See Controlling

colorectal cancer, page 33.) What is known is that

fiber slightly reduces LDL cholesterol, improves insulin

resistance, and is linked to a lower rate of heart disease,

type 2 diabetes, and obesity. eres also some evidence

that fiber might reduce the risk for duodenal ulcers,

breast cancer, and ovarian cancer. Its considered one

of the most important health attributes of foods.

Fiber slows digestion and therefore lowers a foods

glycemic load, which likely helps to prevent diabetes.

By increasing the bulk of foods and creating a feeling

of fullness, fiber may also help you avoid overeating

and becoming overweight.

Studies such as the Nurses Health Study and the

Health Professionals Follow-up Study have found that

people with the lowest rates of heart disease and heart

attack have the highest intakes of fiber. ese studies

formed the basis for the DRIs for fiber.

e DRI for fiber is 38 grams for men up to age 50

and 25 grams for women in this age group. For pregnant

women, the DRI is 28 grams, and for breast-feeding

women, 29 grams. DRIs are lower for people over age 50:

30 grams for men, 21 grams for women. ats because

older people tend to eat less food. On average, Ameri-

cans eat only about 15 grams of fiber a day.

You can probably identify some high-fiber foods,

such as bran cereals and whole-grain bread (see Table

2). But not all foods billed as high-fiber really have

much; read the labels on packaged foods to see the

number of grams of fiber they contain. You can be

sure of getting fiber if you eat fruits, vegetables, and

whole-grain foods such as whole-wheat bread, brown

rice, bran, or oats each day.

Fiber can also take the form of over-the-counter

supplements, which come as pills or powders. ese

provide some of the same benefits as fiber in foods.

Table 2 Good sources of fiber

FOOD FIBER CONTENT IN GRAMS*

Split peas, cooked, 1 cup 16.3

Red kidney beans, boiled, 1 cup 13.1

Raspberries, raw, 1 cup 8.0

Whole-wheat spaghetti, 1 cup 6.3

Oat-bran muffin, medium 5.2

Pear, medium with skin 5.1

Broccoli, boiled, 1 cup 5.1

Apple, medium with skin 4.4

Oatmeal, quick, regular, or instant,cooked, 1 cup 4.0

Green beans, cooked, 1 cup 4.0

Brown rice, cooked, 1 cup 3.5

Popcorn, air-popped, 2 cups 2.3

Whole-wheat bread, one slice 1.9

*Fiber content can vary among brands and varieties.

Source: USDA National Nutrient Database for Standard Reference, 2007.



15/53


But foods naturally high in fiber have the edge, as they

help you feel full on fewer calories, which can help

keep your weight in check. Fiber pills dont provide

that feeling of fullness.If you decide to take fiber sup-

plements, be sure to take them with plenty of water to

maximize their benefits.

Here are some ways to make sure that your diet

meets the DRI for fiber.

Eat whole-grain cereal for breakfast. Oats are an

excellent choice, particularly steel-cut oats, which

have the most fiber and the lowest glycemic index. If

you prefer cold cereal, choose products that contain

bran or list whole wheat, oats, barley, or another whole

grain first on the list of ingredients.Choose whole-grain breads.As with cereals, true

whole-grain breads list a whole grain first in the ingre-

dients. Whole-grain sliced bread, pita bread, and rolls

are equally good.Skip the French fries and baked potatoes.Instead of

white potatoes, eat sweet potatoes (sometimes called

yams). Instead of white rice, eat brown rice or another

intact grain as a side dish. Good choices are buck-

wheat (kasha), bulgur, millet, quinoa, and barley.Try whole-wheat pizza and pasta.Prepared pizzas

made with whole-wheat crust are joining whole-wheat

pastas on supermarket shelves. Many are now made

with a variety of flour or flour blends that look white

and cook up lighter, but are actually whole wheat. Tra-

ditional brown whole-wheat pasta is a great choice,

too, but if it doesnt appeal to you, another option is to

mix whole-wheat pasta with regular white pasta.Cook with whole-wheat flour.You can make breads,

muffins, and other home-baked goods healthier if you

mix whole-wheat flour with white flour. Many stores

sell a multigrain pancake mix you can use for pan-

cakes or waffles. Or instead of traditional whole-wheat

flour, buy white whole-wheat flour, which has a finer

grain than traditional whole-wheat flour and looks

white. It can be substituted for regular white flour

in many recipes. If you use traditional whole-wheat

flour, a straight substitution wont work for every rec-

ipe, because whole-wheat flour is heavier than white

flour. Try starting with a ratio of one part whole wheat

to three parts white to see if you like the results. If you

think the dish could stand a heavier, grainier texture,

try increasing the share of whole-wheat flour. You may

need to increase the amount of liquid at the same time.

Update on proteinHow much protein do you need? at question has

been the subject of debate for decades, and the range

set by the DRIs is wide: 10% to 35% of your daily calo-

The soy story

For a long time, soybean-based beverages and foods likesoy milk and tofu were the royalty of health foods: vegetar-ian, rich in protein, maybe responsible for the lower ratesof heart disease and cancer in China and Japan. That manyAmericans had to acquire a taste for soy made it seemeven healthier in that eat-your-peas way.

Early research suggested that soy protein was hearthealthy because it could lower LDL (bad) cholesterol lev-els, but subsequent studies and judgments have dampenedthat enthusiasm. The results for soy protein have beenso unimpressive that the American Heart Association hasasked the FDA to rescind its 1999 decision that allowedfood companies to label soy products as having heartdiseasereducing benefits.

There have also been worries that the estrogen-likechemicals in soy, called isoflavones (pronounced eye-so-FLAY-vones), might promote the growth of estrogen-sensitive cells and therefore increase the chance of breastcancer recurrence. Study results reported in 2009 in the

Journal of the American Medical Association(JAMA) allaythat concern to some extent.

But how soy and its isoflavones behave in the body iscomplicated. In some partssuch as boneisoflavonesappear to mimic estrogen, occupying the same receptorsand therefore having a similar, if weaker, effect. If soys iso-flavones impersonate estrogen in bone, thats a good thing,because estrogen protects against bone loss by inhibitingosteoclasts, cells that break down bone, and stimulatingosteoblasts, cells that build it up. But in other parts of thebodythe breast, for examplethe estrogen-like effectsof isoflavones might mean extra cell growth and division

and an increase in the risk of a cancer developing.The bottom line: Soy has emerged from the thousands

of studies a bit humbled. Its an excellent source of protein,which is especially important to vegetarians and veganswho need plant-based protein. And, yes, there are manynutritionally valid reasons to steer toward a vegetariandiet. But current science suggests that although soy is arelatively healthy food choice, it is not a particularly impor-tant player in preventing disease.



16/53


ries can come from protein. For most men and women,

protein provides about 15% of their total daily calories,

which is right in the ballpark. Youre better off, how-

ever, if you choose proteins from foods like fish, skin-

less chicken, beans, soy, nuts, and whole grains.

Protein is everywhere in your body. Its in your

muscle, organs, bone, skin, and every other body part

or tissue. It has many functions, including building the

enzymes that trigger many of the important chemical

reactions. About 20 amino acids supply the raw mate-

rial for the bodys proteins. Following genetic instruc-

tions, the body strings together these amino acids into

chains to make the specific proteins it needs. If those

amino acids arent available, your body scavenges pro-

tein from its tissues to get them.

Ideally, the body needs a daily supply of amino

acids to make new proteins. is supply comes from

the protein in food. A lack of protein in the diet can

slow growth, reduce muscle mass, lower immunity,

weaken the heart and respiratory system, and even

cause death. Most people in the United States and other

industrialized countries eat plenty of protein, though.

So how much protein should you eat? In estab-

lishing the upper limit of 35%, the Institute of Medi-

cine cautioned against exceeding that amount because

some studies show that high-protein diets may pro-

mote some diseases, such as osteoporosis. When you

eat a lot of protein, especially animal protein, your

body draws some calcium out of your bones to help

metabolize it. But so long as you eat sufficient calcium

your bones will not suffer.

Indeed, studies suggest that eating plenty of pro-

tein may reduce heart disease. In the Nurses Health

Study, the women who ate the most proteinwhich

in this analysis was about 25% of their daily calories

were 25% less likely to have had a heart attack or to

have died of heart disease than the women who ate the

least protein, 15% of their calories. is finding agrees

with the 2005 results of the OmniHeart Study, which

showed that increasing dietary protein from 15% to

25% lowered blood pressure, LDL cholesterol, triglyc-

erides, and estimated risk of heart disease.

What kind of protein is best? When it comes to

foods that prevent or promote disease, experts know

less about dietary protein than they do about fats

and carbohydrates. Still, large, ongoing studies have

revealed some connections between the type of pro-

tein people eat and their risk for particular illnesses.

Of particular interest is whether protein from

vegetable sourcessuch as lentils, beans, and nuts

Fish is an excellent source of protein, and its healthy oils pro-tect against cardiovascular disease. However, nearly all fishand shellfish contain traces of mercury, a toxic metal, andsome seafood contains other pollutants known as POPs. Assmall fish are eaten by larger fish up the food chain, concen-trations of mercury and POPs increase, so that large, preda-tory deep-ocean fish tend to contain the highest levels. Thatmakes it best to avoid eating these large fish, such as shark,swordfish, tilefish, and king mackerel.

Because a diet rich in seafood protects the heart and

benefits neurological development, fish remains an impor-tant component of a healthy diet.Recommendation: Most adults can safely eat about

12 ounces (two 6-ounce servings) of a variety of cookedseafood a week as long as they avoid the large predatoryocean fish mentioned above and pay attention to local sea-food advisories.

For women who are pregnant or may become pregnant,nursing mothers, and children ages 12 and younger, caution is

needed to avoid potential harm to a fetuss or a young childsdeveloping nervous system. The same amount, 12 ounces, isconsidered safe with these additional guidelines:

Eat up to 12 ounces (two average meals) a week of a vari-ety of fish and shellfish that are lower in mercury. Five ofthe most commonly eaten fish that are low in mercury areshrimp, canned light tuna, salmon, pollock, and catfish.

Another commonly eaten fish, albacore (white) tuna,has more mercury than canned light tuna. So, when choos-ing your fish and shellfish, eat no more than 6 ounces (one

average meal) of albacore tuna per week.Check local advisories about the safety of fish caught by

family and friends in your local lakes, rivers, and coastalareas. If no advice is available, eat up to 6 ounces (oneaverage meal) per week of fish from local waters, but dontconsume any other fish during that week.

Follow these same recommendations when feeding fish andshellfish to your young child, but serve smaller portions.

What to do about mercury in fish



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is healthier than protein from meat, which is a major

source of protein in the Western diet. Evidence sug-

gests that substituting vegetable protein for animal

protein may lower the risk for heart disease. In an anal-

ysis of Nurses Health Study data, a low- carbohydrate

diet moderately lowered the risk of coronary artery

disease, but only when the fat and protein came from

vegetable sources, according to an article published in

2006 in Te New England Journal of Medicine.

Again in 2010, when researchers from the Harvard

School of Public Health analyzed more Nurses Health

Study data, they found that eating one serving per day of

nuts, fish, or chicken in place of red meat lowered the risk

of heart disease by 30%. e study concluded that shi-

ing to protein-rich foods other than red meat could play

an important role in lowering the risk of heart disease.

Processed meats may be the real culprit. A study

published in the journal Circulation in 2010analyzed

data from 20 studies of diet and health from 1.2 mil-

lion initially healthy participants, about 3% of whom

went on to develop heart disease, diabetes, or stroke.

Results showed that red meat wasnt associated with

heart disease or type 2 diabetes as long as it was

unprocessed. Processed meat, such as bacon and hot

dogs, boosted the risk of heart disease by 42% and

type 2 diabetes by 19%.

Still, eating red meat (beef, pork, and lamb) or

processed meats increases the risk of colon cancer.

One possible explanation is that cooking meat at high

temperatures, such as on the grill, produces cancer-

causing substances called heterocyclic amines, among

others. Or the culprit might be the nitrates used in

processing the meat rather than meat itself or the

cooking method. In any event, youre probably much

better off with natural peanut butter or hummus on

your sandwich rather than ham, salami, or baloney.

Over all, there are plenty of reasons to favor plant

proteinsuch as protein-rich vegetables and beans

over red and processed meats. ese plant proteins

come in healthier packages than meat protein (see

Table 3). And not only are these plant-based foods a

good source of healthy polyunsaturated and monoun-

saturated fat, they also provide fiber, which has several

health benefits (see Fiber: e workhorse, page 11)

as well as vitamins and minerals.

e best animal sources of protein are fish and

poultry, because theyre relatively low in saturated fat.

Fish, especially fatty fish such as salmon, also provide

omega-3 fats, which help prevent heart attacks, sudden

cardiac death, and certain types of stroke by decreasing

blood clots, erratic heart rhythm, inflammation, and tri-

glycerides, while raising beneficial HDL cholesterol. Fish

and chicken are good options but should still be con-

sidered accessories to your diet, filling just one quarter

of your plate, while filling the remaining three quarters

with whole grains, vegetables, beans, and other produce.

If you eat red meat, make it only an occasional part of

your diet; opt for small portions, choose lean cuts, and

to minimize your colon cancer riskavoid charring

your meat on the grill. Also, avoid processed meats, such

as ham, bacon, pastrami, salami, sausage, bratwurst, hot

dogs, and pepperoni, since these foods raise the risk of

colon cancer, heart disease, and diabetes.

Table 3 Good sources of protein

These foods contain lots of protein and little or no unhealthy fat.

FOOD PERCENTAGE OF CALORIES FROM PROTEIN

Fish 87%

Tofu 53%

Skim milk 39%

Low-fat yogurt 33%

Broccoli 28%

Kidney beans 27%

Lentil soup 25%

Peanuts 18%

Source: U.S. Department of Agriculture



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Every day your body produces skin, muscle, and

bone. It churns out red blood that carries nutrients

and oxygen to remote outposts, and it sends nerve sig-

nals skipping along thousands of miles of brain and

body pathways. It also formulates chemical messen-

gers that shuttle from one organ to another, issuing

the instructions that help sustain your life. To do all

that, your body requires at least 30 vitamins, minerals,

and dietary components that your body cant manu-

facture in sufficient amounts. So you need to get them

from foods or other sources.

ese essential vitamins and minerals are oen

called micronutrients because unlike the case with

macronutrientsprotein, fat, and carbohydrates

your body needs only tiny amounts of micronutrients.

Yet failing to get these small quantities virtually guar-

antees disease. Old-time sailors learned that living for

months without fresh fruits or vegetablesthe main

sources of vitamin Ccaused the bleeding gums and

listlessness of scurvy. In some developing countries,

people still become blind from vitamin A deficiency.

And even in the United States, some children develop

the so, deformed bones of rickets because they dont

get enough vitamin D (see Table 4).

Just as a lack of micronutrients can cause sub-

stantial harm to your body, getting sufficient quanti-

ties can provide a substantial benefit. For example, a

combination of calcium, vitamin D, vitamin K, mag-

nesium, and phosphorus protects your bones against

fractures. Many micronutrients interact. Vitamin C,

for example, helps you absorb iron. e interplay of

micronutrients isnt always cooperative, however. For

example, even a minor overload of the mineral man-

ganese can worsen iron deficiency.

Vitamins are different from minerals. A vitamins

chemical structure can be broken down by heat, air,

or acid, whereas minerals hold on to their chemical

structure. at means the minerals in soil and water

easily find their way into your body through the plants,

fish, animals, and fluids you consume. But its tougher

to shuttle vitamins from food and other sources into

your body because cooking, storage, and simple air

exposure can inactivate these fragile components.

Your need for certain nutrients varies with your

age, gender, and other important characteristics. As

a rule, your best strategy is to get vitamins and min-

erals from food, not supplements. A vast amount of

research has shown that you can cut your risk for

chronic disease and disability by following a healthy

diet, as well as exercising regularly and avoiding

smoking. e evidence for taking vitamin and mineral

supplements is much less convincing. ere are likely

many more beneficial components of healthy foods

than the ones scientists have identified so far, as well

as synergistic effects among them.

Today, many foods are fortified with vitamins to

the point where deficiencies are rare. Two important

vitamins, Folic acid and Vitamin D have oen been

singled out by health experts who recommend taking

supplements. But the increasing vitamin fortification

of the food supply has made even these vitamins so

plentiful in food that most people get enough from

food. Here are two examples. Folic acid. One of the most firmly established

links between a vitamin and disease prevention

involves the B vitamin known as folic acid (also called

folate). Women who take folic acid are less likely to

have babies with certain birth defects called neural

tube defects. Because of this, all women of childbear-

ing age are advised to get 400 micrograms (mcg) daily

in foods or supplements to guard against the pos-

sibility of birth defects. Some research suggests that

women of childbearing age should get 800 mcg per

Getting vitamins from food (not pills)

Failing to get the required amounts of the

essential vitamins and minerals virtually

guarantees disease.



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day. You can get this amount through a healthy diet

and a daily multivitamin. Most breads and cereals

are fortified with folic acid and it is plentiful in some

foods including as dark leafy greens, oranges, toma-

toes, and legumes. Vitamin D. is vitamin enables your body to

pluck calcium from food sources passing through

your digestive tract rather than harvesting it from

your bones. It helps prevent osteoporosis and may

protect against some cancers and possibly against car-

diovascular disease, hypertension, diabetes, and auto-

immune disorders.

Exposure to sunlight prompts the skin to man-

ufacture vitamin D, which is why its known as the

sunshine vitamin. e Institutes of medicine rec-

ommends all people younger than age 71 get 600 IU

per day and people 71 and older get 800 IU per day.

Most people can get this amount in food, particularly

if they drink milk which is fortified with vitamin D.

People who live in northern climates or have dark

skin may need supplementation to reach the recom-

mended 800 IU. Do not exceed the Upper Daily Limit

of 4,000 IU.

Fruits and vegetablesWeve known for decades that fruits and vegetables

contain important vitamins, minerals, and other

nutrients. Science has also established that a plant-

based diet that includes lots of fruits and vegetables

can lower your risk of some life-threatening diseases

such as heart disease, the nations No. 1 killer for both

men and women. Moreover, if you pile on the pro-

duce, theres less room for the unhealthy foods.

Its important to note that even though fruits and

vegetables deliver lots of vitamins and other nutri-

ents, you dont get the same benefits by taking vitamin

pills and supplements. Out of hundreds of studies

that have tried to separate individual components

of foods and determine their specific health effects,

only a tiny handful have produced convincing results.

Many have fallen flat. Remember when people were

taking vitamin E for everything from heart disease to

memory loss? How about vitamin C to prevent colds?

Or antioxidants to prevent cancer? Promising early

evidence has failed to pan out for taking these nutri-

ents in pill form.

Fruits and vegetables contain hundreds of com-

ponents known as phytochemicals, the majority of

which have yet to be identified. ese phytochemicals

appear in a vast number of combinations in the plants

found in nature. Fruits and vegetables are also high

in fiber, which serves many functions in the body.

In particular, fiber keeps the digestive system run-

What about antioxidants?

Taking antioxidants in pill form or added to foods doesntprotect health, according to the latest research. Its bestto get these nutrients in their naturally occurring forms:in fruits, vegetables, and whole grains.

The term antioxidants is a catchall for any compound that

can counteract unstable molecules, such as free radicalsthat damage DNA, cell membranes, and other parts ofcells. Free radicals in the body are a natural byproduct ofenergy metabolism and are also generated by exposureto ultraviolet rays, tobacco smoke, and air pollution. Theylack a full complement of electrons, which makes themunstable, so they steal electrons from other molecules,damaging those molecules in the process. Free radicalscan be helpful, too. When cells in your immune systemmuster to fight intruders, the oxygen they use spins offan army of free radicals that destroy viruses, bacteria,and damaged body cells.

Vitamin C can disarm free radicals. Other antioxidantvitamins are vitamin E, beta carotene, and related carot-enoids (a class of orange plant pigments). Antioxidantminerals are selenium and manganese. Many antioxi-dants are chemicals other than vitamins and minerals,including certain pigments and isoflavones. The packageof antioxidants found in fruits and vegetables combinedwith the naturally occurring fiber and phytochemicals inthese foods has a variety of healthful benefits, includinglowering the risk of heart disease, diverticular disease,and many other conditions.

Taking individual antioxidants in supplement form

has not been proven to confer similar health benefits.Findings suggest little overall disease protection fromantioxidant pills. It could be that its the orchestration ofantioxidants naturally present in foods, rather than one ortwo vitamins in high doses, that can lower your risk of se-rious illnesses. So its worthwhile to get your antioxidantsfrom foodssuch as oranges, tomatoes, sweet potatoes,carrots, broccoli, berries, whole grains, and nuts notfrom pills.



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ning smoothly and may reduce the risk of heart dis-

ease, diabetes, some gastrointestinal problems such as

diverticulitis (see e food-health connection, page

26), and obesity. Finally, fruits and vegetables are high

in beneficial minerals such as potassium, which low-

ers blood pressure.

Major studies such as the Nurses Health Study

and the Health Professionals Follow-up Study have

shown that a diet rich in fruits and vegetables can

help lower the risk of hypertension, heart disease, and

stroke, and that people who follow such a diet live

longer than those who dont. e DASH diet study

(see Eating plans for good health, page 29) directly

tested a diet high in fruits and vegetables, and showed

a significant blood pressure reduction. People over age

45 had an especially good response to the dietan

important finding because hypertension and its con-

sequences increase with age.

Can a diet high in fruits and vegetables help pre-

vent cancer? So far, its not clear. Studies show that

such a diet may reduce the risk of some forms of can-

cerprobably esophageal, stomach, and lung can-

cers, according to a review of hundreds of studies by

the International Agency for Research on Cancer. But

a recent study in the Journal of the National Cancer

Institute involving 400,000 men and women followed

over nearly nine years found only a very weak asso-

ciation between fruit and vegetable consumption and a

reduced cancer risk.

ere is some evidence that eating plenty of fruits

and dark green leafy vegetables, such as spinach and

collard greens, may lower the risk of macular degen-

eration, an eye disease that impairs vision. Dark green

leafy vegetables have also been linked to a reduced

risk of type 2 diabetes.

Such findings give fruits and vegetables a promi-

nent place in the Healthy Eating Pyramid, which rec-

ommends eating fruit two to three times a day and

eating vegetables in abundance. Many experts rec-

ommend eating five to 13 servings of fruits and vege-

tables a day (2 cups to 6 cups daily). Yet according

to the Centers for Disease Control and Prevention

(CDC), only 14% of Americans eat five or more serv-

ings daily. A public health campaign, Fruits & Veg-

giesMore Matters, aims to close that gap. e

campaign, a joint project launched by the Produce

for Better Health Foundation and the CDC, suggests

eating more fruits and vegetables at every sitting.

For more information, see the campaigns Web site at

www.fruitsandveggiesmorematters.org.

Colorful choicesThe vibrant colors of fruits and vegetables are more

than just window dressing. Think of the produce

department as a store where you shop for a col-

orful wardrobe: choose lots of different colors for

the greatest impact. The reason to choose foods

of many colors is that the healthiest diet includes

a variety of foods. And when it comes to produce,

color is the most outward sign of the different

nutrients in different plants. To increase the benefit,

Do local and sustainablemean healthy?

Anything that gets people eating whole foods rather thanfactory-produced foods is a good thing. While science hasyet to prove that a peach grown locally on a sustainable ororganic farm is healthier than one shipped in from a far-

away country, the interest in local, sustainable agricultureis raising interest in eating healthy, whole, fresh foods.

Sustainable agriculture refers to the use of traditionalfarming methods to create a self-contained ecosystem thatproduces food while eliminating artificial fertilizers andpesticides, thereby supporting the environment while en-couraging rural farmers way of life. Sustainable agriculturecuts down on farms heavy petroleum use by setting limitson how far food can be trucked from the farm to market.It also reduces petroleum use by growing crops withoutpesticides and fertilizers, most of which are derived frompetroleum. Sustainable cattle graze on grass, providing

natural fertilizer in the form of manure and reducing theneed for the antibiotics used heavily for cattle that live intight quarters and eat grain. Such use of antibiotics encour-ages the development of powerful strains of resistant mi-crobes, thereby increasing antibiotic resistance in general.

These are positive benefits. But is food produced this waymore nutritious? Not enough studies have been done toanswer this question, but farming in an environmentally re-sponsible way to conserve natural resources, reduce waste,and lower energy consumption contributes to a healthyplanet and therefore to human health over all.



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choose produce with deep, rich colors like blueber-

ries, carrots, broccoli, and spinach. Fruits and veg-

etables with deep colors contain the most powerful

phytochemicals.

No single type of fruit or vegetable can deliver all

the beneficial phytochemicals and other substances.

Try to get at least one serving daily from each of the

following categories:

dark green or leafy vegetables (dark lettuce, kale,

spinach, collard greens, broccoli)

yellow or orange fruits and vegetables (squash, car-

rots, nectarines, cantaloupe)

red, blue, and purple fruits and vegetables (red pep-

pers, tomatoes, strawberries, blueberries, beets)

legumes (lentils and other beans)

citrus fruits (oranges, grapefruits, lemons, limes).

Table 4Vitamins and minerals with extra health benefits

VITAMIN OR MINERAL BENEFITSRECOMMENDED AMOUNT

BY AGE

UPPER LIMIT

(UL) PER DAYGOOD FOOD SOURCES

Vitamin B6(pyridoxal, pyridoxine,pyridoxamine)

Helps lower homocysteine levels.Not clear whether it lowers heartdisease risk. Helps make red bloodcells. Influences cognitive abilities andimmune function.

Ages 1950:

Men: 1.3 mgWomen: 1.3 mg

Ages 51+:

Men: 1.7 mg

Women: 1.5 mg

100 mg Meat, fish, poultry,legumes, tofu and othersoy products, potatoes,noncitrus fruits such asbananas and watermelon.

Vitamin B12(cobalamin)

Helps lower homocysteine levels. Notclear whether it lowers heart diseaserisk. Assists in making new cells andbreaking down some fatty acids andamino acids. Protects nerve cells andencourages their nor

healthy eating 2011

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