Food and Nutrition 1021 – Lesley Macaskill – Lecture 003Wednesday, September 25th

Notes

Know Canada's food guide

Know AMDR ranges

Know serving amounts, not necessarily how much an adult or child needs.

Food Labels & Regulations, Phytochemicals

Lecture Objectives

Identify the mandatory components of a food label, describe the purposes of food labels and recall which foods require nutrition facts tables.

Explain the terms used in nutrition facts tables, such as serving size, servings per container, etc.

Differentiate between nutrient amounts and percentages of daily values in the nutrition facts table

Recognize the 13 nutrients required to be on the nutrition facts table and the units for each

Calculate the amount of starch in a food using the information in the nutrition facts table

Provide an example of and describe the difference between biological role claims, health claims, nutrient contents descriptors and nutrition facts.

Recall the diet-related health claims allowed on food labels in Canada.

Choose the most nutrient-dense food when presented with 2 nutrition facts tables.

Identify phytochemicals, potential benefits and food sources discussed in class

Define and list potential benefits of functional foods, probiotics and plant sterols

What Foods don't need a food label or to list nutritional information?

What Food Labels Must Incline

The common or usual name of the product

The name & address of the manufacturer, packer or distributor

The net contents in terms of weight, measure or count

The nutrient contents of the product• Nutrition Facts panel

The ingredients, in descending order of predominance by weight

Nutritional Facts Panel

Must list calories plus 13 core nutrients:

1. Fat (total)2. Saturated Fat3. Trans Fat4. Cholesterol5. Sodium6. Carbohydrate (total)7. Fibre8. Sugars9. Protein10. Vitamin A11. Vitamin C12. Calcium 13. Iron

Sometimes serving size can be misleading.

Nutritional Facts Panel

Percent Daily Values (%DV)• Describes how much a serving of food contributes to your total intake of a nutrient• Based on a diet of 2000 Calories per day• Can be used to determine if a product is low or high in a particular nutrient

Calculating % Daily Value• The Daily Value for iron s 14mg.• You see that a product contains 2 mg of iron.• What is the % DV of iron in this food?

14%

Nutritional Facts can tell you about more nutrients (optional)

Fat, Cholesterol & Sodium

Nutrient amounts and percentages of Daily Values• Grams of fat per serving• Mg of cholesterol• Mg sodium

Carbohydrate

• Grams of carbohydrate per serving including starch, fibre, and sugars◦ Breakdown shows grams of dietary fibre and sugar◦ The sugars include those that occur naturally in the food plus any added sugars.

Example 2 slices of wonder bread

total grams – carbs 37grams fibre – 1 grams sugar – 3starch?

33 – just subtract fibre and sugar

Protein

• Grams of protein per serving• Is there a % DV for protein listed?

In Canada we do not see a % DV for Canada.

The Daily Values are of two typesSome suggest an intake goal to strive forExamples: vitamins A & C

Others constitute healthy daily maximumsExamples: cholesterol, total fat, saturated & trans fat

Nutrient Function Claims

Formerly called “biological roles claims”

A carefully worded, prescribed statement on a food that meets strict criteria that outlines the role a nutrient may have on our biological system.

Health Claims

• Link a food or food component with reduced risk of disease or a condition• New to Canadian labels in 2003• 5 claims are permitted on how diet affects health• The health claim must be followed by a statement that the product is a good source of the

food/food component

Permitted Diet-Related Health Claims – examples

• “moderation in intake of sodium may reduce the risk for high blood pressure”• “diets low in saturated and trans fat may reduce the risk for heart disease”• “a diet rich in a variety of fruits and vegetables may reduce the risk of some types of cancer”• “a healthy diet with adequate calcium and regular exercise may help to achieve strong bones in

children and adolescents and may reduce the risk of osteoporosis in older adults”

Nutrient Content Claims

• Claims about the amount of a nutrient in a food• regulated statements made when a food meets certain criteria• optional• often on the front of food packages• a quick and easy way to get information about a food

Light – can be used on foods that are reduced in fat or reduced in calories.

Nutrient Content Claims – when you want to decrease the amount of certain nutrients

Nutrient Content Descriptors

What Food Products have Nutrition Facts?

Almost all pre-packaged foods have Nutrition Facts, with some exceptions:• fresh fruit and vegetables

Source• con t ain s a u se fu l am ou n t of t h e

nu t r ien t • an ex am p le is “ sou rce o f f ib re ”

High or g ood

sou rce

• Prov id es 1 5% or m ore of t h e DV of t h e n u t r ien t

• an ex am p le is “ g ood sou rce o f 9 essen t ia l nu t r ien t s”

Very Hig h or

Ex ce llen t sou rce

• Prov id es 2 5% or m ore of t h e DV of t h e n u t r ien t

• an ex am p le is “ ex ce llen t sou rce o f ca lc iu m ”

Free• none or hard ly any of t h is n u t r ien t• an ex am p le is “ sod iu m free”

Low• a sm all am oun t• an ex am p le is “ low fat ”

Reduced

• at least 25 % less of t he nu t r ien t t h an a sim ila r p roduct

• an ex am p le is “ reduced in Calor ies”

Lig h t • can be used on foods t hat are reduced in fa t or reduced in Calo r ies

• raw meat/poultry (except ground), fish and seafood• foods prepared or processed at the store

◦ bakery items, sausage, salads• foods that contain very few nutrients

◦ coffee beans, tea leaves, spices• alcoholic beverages

Use Nutrition Facts to make Informed Food Choices

• to help you choose foods that meet your needs• to easily compare similar foods• to look for foods with more or less of a specific nutrient• to select foods for special diets

Canada must add nutrients to anything made from wheat.

List of Ingredients

• all of the ingredients for a food are listed by weight, from the most to the least (the ingredient that is in the largest amount is listed first)

• is present on prepackaged foods• is a source of allergy information• is a source of certain nutrient information

Phytochemicals

(Plant Chemicals)• foods consist of thousands of different chemicals• Can be beneficial, neutral or harmful• Consider how differently they can affect individuals, at different doses or at different life stages

Research on phytochemicals is in its infancy• What is current today will likely be challenged a year from now by further studies

In most cases, the health benefits observed with intakes of certain foods cannot be ascribed to individual phytochemicals

What do phytochemicals do in the body?

Some phytochemicals have profound effects on the body through actions such as

• Acting as antioxidants

• Mimicking hormones• Altering blood constituents in ways that may protect against some diseases

Flavonoids

Whole Grains, Wine, and Tea• Historically, diets containing whole grains, fruits, vegetables, herbs, spices, teas, and red wines

have been reputed to possess health-promoting qualities• They all contain flavonoid phytochemicals• Flavus means yellow

Red Wine

One flavonoid of red wine/grapes has disease-fighting qualities

However, the amount of it in the wine/grapes may be too low to benefit human health

The potential benefits may not be worth the immediate/potential risk from the alcohol

Flavonoids

flavonoids often impart a bitter taste to food, so food producers may refine away natural flavonoids to produce a milder flavour

• Example: To make white grape juice or white wine, the red, flavonoid-rich grape skins are removed to lighten the flavour and colour of the product◦ This process reduces the flavonoid content

Flavonoids in Chocolate

• The antioxidant effects of dark (bittersweet) chocolate may turn out to be as powerful as those of tea or red wine

• Should you start eating dark chocolate every day?

Soybeans

• Compared to North Americans, Asians living in Asia suffer less frequently from: ◦ osteoporosis◦ cancers, especially of the breast, colon, and prostate◦ heart disease◦ Asian women also suffer fewer menopause symptoms

◦ Asians consume far more soybeans & soy products such as miso, soy drink & tofu than do Westerners

Soybeans

• Soybeans contain phytochemicals known as • phytoestrogens

• Chemical relatives of the human hormone estrogen•• Alter or mimic estrogen’s effects on some body tissues• May reduce some menopausal symptoms such as hot flashes• May also reduce adult bone loss• They also act as antioxidants

Asians consume far more soybeans & soy products such as miso, soy drink & tofu than do Westerners.

We know with certainty that phytoestrogens are plant derived chemical relatives of the human hormone estrogen.

• They weakly mimic or modulate the hormone's effects on some body tissues• The act as antioxidants.

Flaxseed

Historically, people have used flaxseed for relieving constipation or digestive distress.

Currently, flaxseed and its oil are under study for potential health benefits

Contains lignants, compounds converted into biologically active phytoestrogens by bacteria that normally reside in the human intestine

Flaxseed

A review of the literature shows promise in animal studiesSuppressing cancer and shrinking tumour sizes

However, studies on humans are lacking

Risks: may interfere with vitamin and mineral absorption when taking a high daily doseLarge quantities of flaxseed can cause digestive distress

The Bottom Line on Flaxseed

• Although no clear role has been established for flaxseed in the prevention of human cancer◦ Including a spoonful or two of ground flaxseed in the diet may not be a bad idea◦ Flaxseed richly supplies linolenic acid

▪ A needed nutrient often lacking in the North American diet

Tomatoes

People around the world who eat the most tomatoes, about 5 tomato-containing meals per week, are less likely to suffer from cancers of the esophagus, prostate, stomach or than those who avoid tomatoes

Tomatoes

Lycophene is the phytochemical likely promoting this effect • A red pigment with antioxidant activity• Found in guava, papaya, pink grapefruit, tomatoes (especially cooked tomatoes and tomato

products), and watermelon

Tomatoes – Lycopene

Lycopene may inhibit the reproduction of cancer cells• Some research suggests that an increased risk of breast cancer is linked to low blood levels of

lycopene and related compounds• Low blood lycopene also correlates with an elevated incidence of heart disease, heart attack,

and stroke• Lycopene may also protect against the damaging sun rays that cause skin cancer

Phytoestrogens – it's not all good

Phytoestrogen supplement use may involve some risk

one soy phytoestrogen, genistein, when given in high doses in animals appeared to speed division of breast cancer cells in laboratory cultures and in mice.

Instead of suppressing cancer growth it promoted it.

Garlic

Descriptions of its uses for headaches, heart disease, and tumors are recorded in early Egyptian medical writingsIn modern medical research, over 3,000 publications have investigated the potential health benefits of

garlic• Many have reported positive findings

Garlic

Organosulfur compounds in garlic have been shown to inhibit cancer development in lab animalsOthers have shown to improve blood cholesterol levels to promote heart health

Though these findings hold promise, studies of garlic supplements, such as powders and oils, have been disappointing

Bottom Line on Phytochemicals

Researchers who study phytochemicals conclude that the best-known, most effective, and safest sources for phytochemicals are foods, not supplements

Functional Foods

Foods claiming to provide health benefits beyond those of the traditional nutrients

Examples:Chocolate, garlic & soyCholesterol-reducing margarineProbiotic yogurt

Plant Sterols

Newly approved for addition to: spreads, mayonnaise, margarine, salad dressings, yogurt/yogurt drinks, fruit/veg. juices in Canada

Claim to reduce blood cholesterol by up to 15% in just 3 weeks (when combined with a move to a healthy diet)

What are Probiotics?

Microorganisms that are believed to alter the native bacteria in the digestive tract in ways that may reduce diseasesLactobacillus organisms may be useful for improving the diarrhea that often occurs from the use of antibiotic drugs or other causes

• Especially among children

Probiotics

More research is needed to verify suggestions that probiotic preparations may: • alleviate lactose intolerance and allergies• enhance immune function• protect against digestive tract cancers (particularly colon cancer) and ulcers• reduce urinary and vaginal infections in women• lower blood cholesterol

What are prebiotics?

• Non-digestible carbohydrates that act as food for probiotics• Inulin is an example and it is found naturally in many vegetables and grains• Prebiotics are also added to processed foods and can be purchased as a supplement

• Benefits: help to keep a healthy balance of bacteria in the digestive system• Contain fibre and other nutrients

Western in conjunction with Brescia gave yoghurt to HIV+ Africans and it boosted their immune systems.

Other Functional Foods

Is Every Food Functional?• Many functional foods occur in nature

◦ A serving of broccoli sprouts provides a concentrated source of phytochemicals associated with cancer prevention▪ Broccoli itself contains this phytochemical in less impressive but still healthy doses

• Drinking a half-cup of ______________ juice may reduce the incidence of urinary tract infections

Page 52 – Nutritional Facts and Claims on Food Labels

Page 53 + 54 – What's on a Food Label

Page 55 – Nutrient Content Descriptor Terms on Food Labels

Page 56 – Diet Related Health Claims

57 to 60 – Meal Examples with Nutrients

62 – Phytochemical and Functional Food Terms

63 – A Sampling of Phytochemicals, Possible Effects and Food Sources

64 -- How Scientists View Phytochemical, Flavonoids, Antioxidants

65 – Phytochemicals in Fruit and Vegetables

66 – Flaxseed, Tomatoes

67 – Garlic, Supports and Detractors of Phytochemical/Bioactive Compound Supplements, The Concept of Functional Foods

68 – Categories of Functional Foods, Cholesterol reducing margarine, juice, and candies, yogurt, conjugated lionleic acid (CLA)

69 – Tips for Consuming Phytochemicals

72 – Cells

73 – Enzyme, fat cells

74 – Nutritional genomics, tissues, organs, body system, blood, lymph, arteries, veins, capillaries, plasma, extracellular fluid

75 – Blood flow in the cardiovascular system, intracellular fluid

76 – How the body fluids circulate around cells, lungs, intestine, liver, kidneys

77 – Oxygen-carbon dioxide exchange in the lungs, hormones

78 – Pancreas, insulin, glucagon, cortex, hypothalamus, fight-or-flight reaction, nervous system interact with nutritional

79 – Neurotransmitters, epinephrine, norepinephrine, metabolism

80 – The immune system, microbes, antigen, immune system, lymphocytes, phagocytes, t-cells, b-cells, antibodies

Immune system enables the body to resist diseases.

81 – the digestive system, grehlin, why do people like sugar, fat, and salt

82 – digestive tract, digestive system, digest, absorb, peristalsis, segmentation, stomach, sphincter

84 – Chyme, pyloric, small intestine, large intestine, colon, feces

86 – gastric juice, pH, mucus,

87 -- bile, eulsifier, pancreatic juice, bicarbonate

88 – Summary of chemical digestion

89 – villi, microvilli

92 – hiccups, heartburn

93 – antacids, acid reducers, ulcer, hernia, gastroesophageal reflux disease (GERD)

94 – constipation, diarrhea, irritable bowel syndrome, nephrons, bladder

95 – storage systems, glycogen, adipose tissue

96 – variation in nutrient stores

98 – Alcohol