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—page 11—

(Continued onpage 3)

And then therewere three.

For years, Dr. Atkins’ NewDiet Revolution

has dominated best-seller lists.But by last November, Atkinshad company. Dr. Phil’s TheUltimate Weight Solution hadcracked the top ten. And The South Beach Diet satcomfortably at number one.Where it should be.

South Beach isn’t perfect. Its rationale has some flaws.And just because people buya self-help book, you can’tassume that they’ll follow itsadvice (or we’d all be trim,sculpted, happily married,wealthy, and living apurpose-driven life).

But for the first time in along time, one of themost popular weight-lossbooks is recommending ahealthy diet. Whether it

helps those unwanted poundsdisappear any better than otherdiets is another question.

(Continued on page 3)

B y B o n n i e L i e b m a n

H E A L T H L E T T E R

The Scoop

on Doughnuts

—page 13—

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fter all theseyears, pub-lishers knowwhat sells.

And, with a few excep-tions, what’s selling noware books about “goodcarbs.”

Books like The SouthBeach Diet, The Zone, andGood Carbs, Bad Carbsargue that “bad” carbsare making us fat. Eventhe Atkins diet, whichhas urged dieters to limitall carbs since the 1970s,has modeled its recentadvice (especially forPhase 2) after the “good-carb” books. In a nut-shell, here’s what theyclaim:

1. Bad carbs cause a quickrise in blood sugar.

2. High blood sugar raisesblood insulin levels.

3. Insulin leads to weightgain (either by makingthe body store fat or bylowering blood sugar lev-els so much that it causeshunger).

The solution? Simple, saythe books. All dieters haveto do is eat “good” carbs(like whole grains, vegeta-bles, and beans) instead of“bad” carbs (like sugar,white bread, and pota-toes).

Yet most obesity ex-perts, including those whobelieve in that advice,agree that the researchcupboard is bare. “It’s amazing how few good studies havelooked at how different carbohydratesaffect weight loss,” says Walter Willett,chair of the nutrition department atthe Harvard School of Public Health.

“So far, the long-term evidence onweight loss is meager. We need biggerand longer randomized trials.”

slower is better.” Howdo you know whichfoods are which?

“In the early 1980s,Dr. David Jenkins led ateam of Canadianresearchers whodevised a scale to mea-sure the rapidity anddegree with which afixed quantity of foodincreases your bloodsugar,” writes SouthBeach author ArthurAgatston. “They calledit the glycemic index.”

In fact, the index ismuch more compli-cated than most bookspretend.

“People think that afood has a definitiveglycemic index, but itdepends on how thefood is processed,stored, ripened, cut,and cooked,” saysXavier Pi-Sunyer, anobesity expert atColumbia UniversityCollege of Physiciansand Surgeons in NewYork.

Furthermore, dietbooks imply that“good” carbs likewhole grains have alow glycemic index(GI, for short), while“bad” carbs like sugars,white flour, and otherrefined grains have ahigh GI. In fact:

■ Bread is typicallyhigh-GI, whetherwhole-wheat or white,

because it’s made from finely groundflour.

■ Pasta is low-GI, whether whole-wheat or white, but there are varia-tions. “Thin linguine has a higher GIthan thick linguine,” notes Pi-Sunyer.“How would we advise the publicabout this major difference?”

G l y c e m i c C o n f u s i o n

The South Beach Diet calls them “slowsugar” and “fast sugar.” To Good Carbs,Bad Carbs, they’re “tricklers” and“gushers.”

But the message is the same: “As faras obesity is concerned,” says SouthBeach, “fast sugar is worse for you;

C O V E R S T O R Y

“Lose weight! Increase energy! Look great! This book will...show you how to change your life once and for all.”

“I’m not exaggerating when I say that this diet can, as a fringebenefit, save your life.”

“...learn to live a healthier, fuller life from this point forward.”

Guess which of those promises come from which of the three top-sell-ing diet books, Dr. Atkins’ New Diet Revolution, The South Beach Diet,and Dr. Phil’s The Ultimate Weight Solution. (Answer: they’re in order.)Most diet books follow a formula. Amid the dispelled myths, tips, andpersonal success stories, nearly all promise that:

■ it’s not a diet but a way of life,■ the food is delicious and you won’t be hungry,■ you’re overweight because you ate the wrong (not too much) food,■ you’ll lose weight because you’ll eat the right (not less) food, and■ the diet will prevent either the major—or virtually all—diseases.

If you believe all that, we’ve got some old Enron stock for you.

Phot

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C O V E R S T O R Y

■ Rice ranges from high-GI (instantwhite) to low-GI (Uncle Ben’s con-verted white), with brown and long-grain white rice in the middle. “Arewe going to specify for the publicwhich kind of rice they should eat and which kind they shouldn’t?” asksPi-Sunyer.

■ Sugars range from high-GI (glucose)to low-GI (fructose). Sucrose (tablesugar) is smack in the middle. What’smore, “researchers have found no rela-tion between the sugar content offoods and their glycemic index,” saysPi-Sunyer.

And it’s not even clear that the rise inblood sugar that comes from eatinghigh-GI foods leads to high blood insu-lin levels, or that higher insulin leadspeople to overeat, says Pi-Sunyer.1

“The glycemic index may account forless than a quarter of the insulin re-sponse to a food,” he suggests. “Andthere is no evidence that the typicalpost-meal levels of insulin increasefood intake or body weight.”

Which leads to the question: howgood is the evidence that low-glycemic-index foods promote weight loss?

N o M a g i c B u l l e t

You’ll find a glycemic-index ranking offoods in The Zone; Dr. Atkins; GoodCarbs, Bad Carbs; and The New GlucoseRevolution.

But unlike the other books, The New Glucose Revolution was written byscientists who have actually studied theglycemic index. In fact, one of itsauthors, Thomas Wolever of theUniversity of Toronto, was one of theresearchers who helped devise thescale.

The glycemic index is no magicbullet for dieters, says Wolever.

“I’ve yet to see evidence that a low-GI diet aids weight loss,” he explains.“One or two studies show it and anumber of others don’t.”

Despite the “Lose Weight” claim onthe cover of Wolever’s The New GlucoseRevolution, “it’s not really a diet book,”he says. “It’s information about theglycemic index and how to use it forhealth.” Wolever’s research uses a low-glycemic-index diet to lower the risk ofheart disease and to control diabetes.

“The chapter on weight says that alow-GI diet may be helpful for people

the Atkins’ low-evidence revolution

robert Atkins died last spring after falling on the icy

pavement outside his New York City office. A few

months later, his clinic closed its doors for good.

But his work lives on, not only in the diet books that continue to sell like hot-

cakes (low-carb, of course), but in the more than 100 snack bars, frozen dinners,

muffin mixes, ice creams, and other foods and supplements that carry his name.

The pitch: Atkins-brand foods have fewer “net” carbohydrates than conventional

foods. What are net carbs? They’re what’s left after Atkins Nutritionals replaces

some of the foods’ carbs with protein from soy and wheat, and after it deducts

other carbs that, according to the company, have “a minimal impact on blood

sugar.” (The list includes fiber, glycerin, sugar alcohols, and polydextrose.)

The remaining carbohydrates appear in the “Net Atkins Count” circle on the

package. Creative accounting? You bet. Good science? Hardly.

■ Atkins Nutritionals won’t say whether it has tested its foods to make sure thatthey don’t raise blood sugar. Just because a food is sweetened with glycerin,sugar alcohols, or other sugar substitutes doesn’t necessarily mean that it’sgentler on your blood sugar. For example, a sugar-free apple muffin or bananacake raises blood sugar as much as its sugar-sweetened counterpart.1

■ Atkins’ books claim that only carbs that raise blood sugar cause weight gain,but the evidence is scanty.

What’s more, low-carb foods aren’t cheap. A 12-ounce box of pasta costs$5.99. Four cups of instant soup run $12. Fifteen brownies will set you back $32.

SupplementsAtkins Nutritionals also sells pills to “help break up a weight loss logjam.” Amongthe ones Atkins recommends:

■ Coenzyme Q10: Take 100 mg a day, since an “exploratory” study two decadesago found that people who took CoQ10 lost more weight than people who didn’t.Reality check: The study, which was never published in a peer-reviewed scien-tific journal, was never followed up.

■ Carnitine: Take 1,500 mg a day, just in case you have a deficiency of theamino-acid derivative.Reality check: No good research shows that overweight people are deficient incarnitine, or that taking 1,500 mg a day helps people lose weight.2

■ Chromium: Take up to 1,000 micrograms a day, because preliminary research15 years ago suggested that it helped build muscle and burn fat.Reality check: Better studies since then have come up empty.

—David Schardt

1 Amer. J. Clin. Nutr. 76: 5, 2002.2 Int. J. Sport Nutr. Exer. Metab. 10: 199, 2000.

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who want to lose weight,” he says.“But the best way to do that is toreduce calorie intake and increase activ-ity level.”

When Wolever put people on low-GIdiets to control their diabetes, thepounds didn’t melt away. “Peopletended to lose a little weight, but itwasn’t significant,” he explains. “Andwe found no differences in how fullthey felt on low-GI foods.”

In fact, in one study of 35 peoplewith diabetes, those who were givenhigh-GI cereals (corn flakes, puffed rice,or crispy rice) lost two pounds after sixweeks, while those who got low-GIcereals (Bran Buds or a Cheerios-typecereal, plus an added fiber called psyl-lium) lost no weight.2

Others agree that the research is in itsinfancy.

“A low-GI diet may suppress hunger.But until there is research over the longterm, we just don’t know,” says SusanRoberts of the Jean Mayer U.S. Depart-ment of Agriculture Human NutritionResearch Center on Aging at TuftsUniversity in Boston.

A recent review of the evidencereached this conclusion:3 “The idealhuman intervention study on low-GIvs high-GI diets has not yet beenconducted.”

For example, in many studies, thediets differ in fiber or protein content,not just in the glycemic index of theirfoods. “A lot of articles hypothesizeabout the glycemic index, but there arenot a lot of controlled studies to seewhether a low-GI diet works,” saysBonnie Brehm, an obesity researcher atthe University of Cincinnati.

B e y o n d t h e I n d e x

If a low-GI diet is no guarantee that we’llall look like Demi Moore and what’s-his-name, so what? Maybe it’s not a lowglycemic index, but more whole grainsor fiber, that can keep us slim.

“It’s hard to draw conclusionsbecause the studies on fiber are all toodifferent—some use supplements, someuse real food, some have a small fiberincrease, some have a modestly bigincrease,” says Tufts’ Susan Roberts.

Studies on whole grains and weightare even scarcer. “Our study foundthat diets higher in whole grains andfiber slow weight gain compared to

Dr. Phil’s pills

if you hit it right, a popular diet book can be a

gold mine. But the big players know how to dig

even deeper. Dr. Phil—who at 6’4” and 240 pounds

is clearly overweight—wants fans to pay $120 for his

vitamins and up to $90 for his bars and drink mixes

every month. Here’s the scoop:

Weight Management SupplementsIf you’ve got a waist smaller than 35 inches (women) or 40 inches (men), Dr. Philwants you to buy his Weight Management Supplement & Complete Multivitaminfor Pear Body Types. If you have a larger waist, you need his supplement for AppleBody Types. Either way, it’s 12 pills a day, 60 bucks a month.

What’s the difference? Very little. Both contain the same 23 vitamins and miner-als, plus carnitine (an amino-acid derivative) and four herbs. The “pear” pills alsohave a speck of soy isoflavones, green tea, and Rhodiola rosea root. In contrast, the“apple” pills contain Gymnema sylvestre leaves, vanadium, and white kidney beanextract.

Never mind that there are no studies showing that the supplements promoteweight loss in anyone, pear or apple. No matter what fruit your body looks like,Dr. Phil thinks you need to “take your weight management efforts to the nextlevel” by plunking down an additional $60 a month on 10 “Intensifier” pills a day.The Intensifiers contain:

■ Coenzyme Q10: “Required for the production of energy in the body.”Reality check: May help with congestive heart failure, not excess weight.

■ Conjugated linoleic acid (CLA): “May reduce the deposit of excess body fatand increase the ratio of lean body mass to fat, when combined with a low-calorie diet and exercise.”Reality check: May also cause liver damage and worsen insulin resistance.

■ EPA and DHA: “Support healthy body membranes and heart health.”Reality check: These omega-3 fats, which are found in fish oil, may help preventsudden cardiac death, but have nothing to do with weight loss.

■ Tyrosine and L-theanine: “May help reduce every day stress.”Reality check: No good studies back up the benefits of theanine or the trivialamount of tyrosine in Dr. Phil’s Intensifier pills.

■ Vitamin C: “Protects your body against the damaging effects of free radicals.”Reality check: There is no evidence that vitamin C has any impact on weight.

Nutrition ShakesYou’re nobody in the weight-loss game unless you sell a meal replacement shake.Shape Up! Shakes contain “scientifically researched levels of ingredients that canhelp you change your behavior to take control of your weight,” says Dr. Phil.

In fact, they’re just a run-of-the-mill powder made from milk, eight kinds of fiber,and added vitamins (which you don’t need if you’re already taking his 22 pills aday...or your own inexpensive multi).

Nutrition BarsDr. Phil’s Shape Up! bars are concoctions of sugars, oil, soy protein, fiber, and stillmore added vitamins. So much for his advice to keep sugars and fats “off-limits ifyou want to successfully control your weight.”

—David Schardt

C O V E R S T O R Y

(continued on p. 8)

C O V E R S T O R Y

6 N U T R I T I O N A C T I O N H E A L T H L E T T E R ■ J A N U A R Y / F E B R U A R Y 2 0 0 4

The SouthBeach DietBy ArthurAgatston

NAME

Switching togood carbs stopsinsulin resistance,cures cravings,and causesweight loss.Good fats protectthe heart andprevent hunger.

Yes: Seafood,chicken breast, leanmeat, low-fat cheese,most veggies, nuts,oils; (later) wholegrains, most fruits,low-fat milk oryogurt, beans.

Less: Fatty meats,full-fat cheese, re-fined grains, sweets,juice, potatoes.

Restricts car-rots, bananas,pineapple, andwatermelon.

You won’t everbe hungry(despite menusthat average just1,200 calories aday).

The UltimateWeightSolutionBy PhilMcGraw

Foods that taketime to prepareand chew lead toweight loss. Other“Keys to WeightLoss Freedom”include “no-failenvironment,”“right thinking,”“healing feelings,”and “circle ofsupport.”

Yes: Seafood, poul-try, meat, low-fatdairy, whole grains,most veggies, fruits,(limited) oils.

Less: Fatty meats,sweets, refinedgrains, full-fat dairy,microwaveableentrées, fried foods.

Readers maybuy Dr. Phil’sexpensive,questionablesupplements,bars, andshakes (see“Dr. Phil’sPills,” p. 5).

“Each of thesenutrients [in hissupplements]has solid clinicalevidence (and arecord of safety)behind it.”

Dr. Atkins’ New DietRevolutionBy Robert C. Atkins

A low-carb diet isthe key to weightloss (and goodhealth) becausecarbs cause highinsulin levels.

Yes: Seafood, poul-try, meat, eggs,cheese, salad veg-gies, oils, butter,cream; (later) limitedamounts of nuts,fruits, wine, beans,veggies, wholegrains.

Less: Sweets, refinedgrains, milk, yogurt.

Long-termsafety notestablished.

“Only by doingAtkins can youlose weight eat-ing the samenumber of calo-ries on whichyou used to gainweight.”

GoodCarbs, Bad CarbsBy JohannaBurani & Linda Rao

Switching fromhigh-glycemic-index foods(“gushers”) tolow-glycemic-index foods(“tricklers”) aidsweight loss.

Yes: Sourdoughbread, beans, mostfruits, low-fat dairy,most veggies, chips,pasta, Special K,pudding, poundcake.

Less: White bread,sweets, Raisin Bran,potatoes, water-melon.

Dieters mayassume thatthey can eat asmany “trick-lers” as theywant and notgain weight.

“…in spite of thetitle Good Carbs,Bad Carbs, thereare no badcarbs.”

CLAIM WHAT YOU EAT

IS THE SCIENCE SOLID?

IS THE DIETHEALTHY?

WORSTFEATURE

MOSTPREPOSTEROUS

CLAIM

Mostlyhealthy foods.

Healthy version ofAtkins diet that’sbacked by solid evi-dence on fats andheart disease.

Tough-love manualthat relies more onDr. Phil’s opinionthan on science.

Mostlyhealthy foods.

Gives nomenus, recipes,or advice on howmuch of what toeat.

Too much redmeat may raiserisk of colon orprostate cancer.

Lack of fiber,vegetables, andfruits may raiserisk of heart dis-ease, stroke, can-cer, diverticulosis,and constipation.

Low-carb “bible”overstates the resultsof weak studies andthe evidence onsupplements. (How-ever, in recent smallstudies, people lostmore weight after6—but not 12—months on Atkinsthan on a typicaldiet.)

Dumbed-down,sloppy version ofThe New GlucoseRevolution thatinflates the impor-tance of theglycemic index.

Mostlyhealthy foods.

Few recipes,menus, or spe-cifics.

Some low-glycemic-indexfoods are un-healthy (e.g.,sponge cake,chips, chocolatebars).

s it the title? Is it the promises? Is it word of mouth? It’s not clear how people pick a diet book, but onething’s for sure: the decision is rarely based on good science. Here’s our take on the most popular diet books.Since no large long-term studies have pitted them head-to-head, we can’t evaluate the diets’ ability to make

you skinnier. Instead, we’ve graded each book’s scientific credibility (“Is the Science Solid?”) and whether the dietit recommends is healthy. (In “What You Eat,” “Yes” means frequently, “Less” means rarely, if ever.)

The books are listed in order according to Amazon.com’s top-selling “Diet and Weight Loss” books in mid-November.We added Dean Ornish’s Eat More, Weigh Less and the Weight Watchers cookbook because a recent study testedboth diets. We excluded other cookbooks and how-to spin-offs of the top-sellers.

The chart gives only thumbnail sketches. See the books for more details.

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NAME CLAIM WHAT YOU EAT

IS THE SCIENCE SOLID?

IS THE DIETHEALTHY?

WORSTFEATURE

MOSTPREPOSTEROUS

CLAIM

Eat Right 4Your TypeBy Peter J.D’Adamo &CatherineWhitney

Your blood typedetermines yourdiet, supple-ments, and per-sonality because itis “the key to yourbody’s entireimmune system.”

Yes:Type O: Meat, sea-food, fruits, veggies.(Less: Wheat, beans.)Type A: Fruits, veg-gies, beans, mostseafood. (Less:Meat, dairy, wheat.)Type B: Meat, beans,fruits, veggies. (Less:Chicken, wheat.)Type AB: Seafood,dairy, fruits, veggies. (Less: Red meat.)

May convincepeople to usethese diets totreat cancer,asthma, infec-tions, diabetes,arthritis, hyper-tension, andinfertility.

“If you are aType A womanwith a familyhistory of breastcancer, considerintroducingsnails into yourdiet.”

The NewGlucoseRevolutionBy JennieBrand-Miller,ThomasWolever, KayeFoster-Powell,and StephenColagiuri

Low-glycemic-index foods keepyou satisfiedlonger and helpyou burn morebody fat and lessmuscle.

Yes: Beans, pasta,most fruits, veggies,low-fat dairy, poul-try, lean meat,seafood.

Less: Potatoes,white bread, fattymeats, full-fat dairy,watermelon.

Advice is diffi-cult to followbecause gly-cemic indexvaries so muchfor each food(e.g., bananasrange from 30to 70).

Low-glycemic-index diets areeasy to teachand easy tolearn.

WeightWatchers NewCompleteCookbook

Following a pointsystem helpsdieters cut caloriesand lose weight.

Yes: Fruits, veggies,low-fat dairy, poul-try, seafood, leanmeats, grains.

Less: None.

SomepackagedWeightWatchers foods(none are men-tioned in thecookbook)aren’t exactlynutritious.

Not applicable(cookbook).

Eat More, Weigh LessBy DeanOrnish

Slashing fat is thekey to weight loss.

Yes: Beans, fruits,veggies, grains, (lim-ited) non-fat dairy.

Less: Meat, seafood,poultry, oils, nuts,butter, dairy (exceptnon-fat), sweets,alcohol.

Unnecessarilyrestricts sea-food, turkeyand chickenbreast, oils,nuts, and fat-free dairy.

Eating a very-low-fat vegetar-ian diet is easy.

About as scientific asa horoscope.

Not applicable(diet variesaccording toblood type,ancestry, etc.).

No science cited,but its sensibleadvice is used bymillions.

Mostlyhealthy foods.

Reasonable interpre-tation of the sci-ence, thoughstronger for heartdisease and diabetesthan for weight loss.

Mostlyhealthy foods.

Fuzzy limitson low-glycemic-index foods,including pasta,sourdoughbread, honey,some sugarycereals, andsome dried fruits.

Diet worked (whencombined withexercise and stressreduction) in asmall-but-long-termstudy.

Mostlyhealthy foods.

Too manycarbs may raisetriglycerides andlower HDL(“good”) choles-terol if peopledon’t exercise,lose weight, andreduce stress.

Enter The ZoneBy Barry Sears

Eating the rightmix of the rightfats, carbs, andprotein keeps youtrim and healthyby loweringinsulin.

Yes: Seafood, poul-try, lean meat, fruits,most veggies, low-fat dairy, nuts.

Less: Fatty meats,full-fat dairy, butter,shortening, (limited)grains, sweets,potatoes, carrots,bananas.

May convincepeople to usethe diet to treatcancer, AIDS,chronic pain,impotence,alcoholism,depression,and arthritis.

“I believe thatthe hormonalbenefits gainedfrom a Zone-favorable diet willbe consideredthe primarytreatment for allchronic diseasestates, with drugsbeing used assecondarybackup.”

Exaggerates evi-dence that the Zonediet is the key toweight loss andimplies that the dietcan cure virtuallyevery disease.

Mostlyhealthy foods.

Few recipesor menus.

The Fat Flush PlanBy AnnLouiseGittleman

Detoxifying theliver and lymphsystem, takingomega-3 fats thatburn calories, andavoiding insulin-raising carbs pro-mote weight loss.

Yes: Eggs, meat,poultry, seafood,most veggies, fruits,organic coffee, nuts,cranberry juice;(later) beans, wholegrains, cheese.

Less: Sweets, butter,margarine, refinedgrains, caffeine, milk,yogurt, yeast.

Useless fat-flush kit costs$68 per monthfor vitamins,omega-3 fats,etc., that “trig-ger fat burn-ing...and nour-ish our tiredand over-worked livers.”

“The best way togive those fattydeposits [in yourthighs and arms]the old heave-hois by cleansingyour lymphaticsystem with abouncing actionor by movingyour arms whilewalking briskly.”

Kooky mishmash ofold detox lore andnew good-carbtheory.

Mostlyhealthy foods.

Too much redmeat and eggs.

diets high in refined carbohydrates,”says Eric Rimm of the Harvard Schoolof Public Health.

But the difference in weight wassmall—only a few pounds over 12years—and it’s impossible to knowwhether whole-grain eaters did otherthings to avoid obesity.4

“Would I like to see trials that ran-domly assign people to eat wholegrains or refined grains for a year?” asksRimm. “Sure.” In the meantime, herecommends whole grains for every-one, overweight or not.

“There’s a growing body of evidencethat whole grains are more beneficialthan refined grains to reduce the risk ofheart disease, diabetes, and obesity.”

D i e t v s D i e t

After years of ignoring popular dietbooks, researchers recently started test-ing Dr. Atkins head-to-head against“conventional diets,” which cut calo-ries mostly from fat. Three researchteams released preliminary results lastyear.5-7

“Our study, as well as the two others,were all relatively small and short-term,but the results of all three were consis-tent,” says the University of Cincin-nati’s Bonnie Brehm. “The healthyobese women in our study lost moreweight on the Atkins diet than on theAmerican Heart Association’s diet.”

Brehm’s study lasted only sixmonths. In another study, the Atkinsdieters also lost more weight, but thedifference between the two groups dis-appeared after a year. Still, what dieterwouldn’t jump at the chance to loseextra weight for six months?

What’s more, “we don’t have asmuch reservation as we used to aboutthe cardiovascular risk factors of anAtkins diet,” adds Brehm. “The weightloss seems to override the high satu-rated fat content of the diet.”

But what happens to LDL (“bad”)cholesterol and other risk factors forheart disease once weight stabilizes isan open question, she adds. Also, herstudy tested women with normal, nothigh, cholesterol.

“Is the Atkins diet effective?” asksBrehm. “Yes. But I still wouldn’t rec-ommend it until we have moreresearch on its safety.”

Others are also hesitant to endorse adiet that’s loaded with red meat.

“The Atkins diet is potentially relatedto a long-term risk of cancer” if peoplestay on it long enough, says Harvard’sEric Rimm.

A few months on Atkins may notcause problems. “But two years on ared meat diet could initiate a cancer,”he adds. “It could show up as a polypin seven years and as colon cancer inten.”

And Brehm worries about too littlefiber, fruits, and vegetables on anAtkins-type low-carb diet.

“The women in our study averagedonly five grams of fiber a day,” shenotes. (That’s one-sixth of whatexperts recommend.) And despitewhat Atkins claims, “they did haveconstipation problems.”

Phase 2 of the Atkins diet allowsmore fruits and vegetables, sheacknowledges. “But if you don’t loseenough weight in Phase 2, you have tomove back to Phase 1, so you’re onthat restricted diet longer than thebook says.

“I don’t see the medical communityrecommending Atkins as a healthy dietbecause it’s so restricted,” says Brehm.“You miss out on fiber and any phyto-chemicals in fruits and vegetables thatwe may not even know about yet.”

T h e B o t t o m L i n e

Where does that leave the ever-expand-ing legions of dieters?

According to media reports lastNovember, a new study found no dif-

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C O V E R S T O R Y

ference in weight loss on four diets—Atkins, The Zone, Dean Ornish, andWeight Watchers. But until the studyhas been vetted and published, it’s tooearly to weigh its conclusions.

Ornish’s book, Eat More, Weigh Less,resurrects an old question: shoulddieters eat a very-low-fat diet, whichgets 70 to 75 percent of its caloriesfrom carbohydrates?

Carbs shouldn’t exceed 60 or 65percent of calories, say the NationalHeart, Lung, and Blood Institute, theAmerican Heart Association, and theNational Academy of Sciences.

“Too many carbs may raise triglyc-erides and lower HDL [good] choles-terol,” says Alice Lichtenstein of Tufts’Human Nutrition Research Center onAging, who coauthored the AmericanHeart Association’s guidelines on very-low-fat diets.

That didn’t happen when Ornish put35 people with heart disease in his Life-style Heart Trial for five years. (Theirarteries became less clogged.) Was it allthe fiber they were eating? Possibly.

“It’s also possible that other parts ofOrnish’s program—vigorous exercise,stress reduction, and weight loss—pro-tected them,” says Lichtenstein. “Ifpeople don’t follow his diet and otheradvice closely, too many carbs couldcause trouble.”

Ornish aside, people who think theycan eat any and all carbs without con-sequences are wrong.

“When the pendulum swung as far asit could to low-fat diets in the 1980s,we may have gone too far recommend-ing higher carbs,” says Brehm. “Peoplemay have lost sight of the fact thatcarbs have calories.”

Now they know better.“We’re saying that you need to cut

back on carbs, and you can eat moreunsaturated fat,” Brehm explains.“People may be ready for a morerefined tool that separates good carbsand fats from bad.” Sound familiar?

“The South Beach Diet teaches youto rely on the right carbs and the rightfats,” says the book’s first page.

1 Amer. J. Clin. Nutr. 76: 290S, 2002.2 Amer. J. Clin. Nutr. 72: 439, 2000.3 Obesity Reviews 3: 245, 2002.4 Amer. J. Clin. Nutr. 78: 920, 2003.5 J. Clin. Endocrinol. Metab. 88: 1617, 2003.6 New Eng. J. Med. 348: 2074, 2003.7 New Eng. J. Med. 348: 2082, 2003.

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