Truth in Advertising in the Fitness Industry

Calorie Myths

More than the ScoreSeptember 8, 2007

Glenn Gaesser, Ph.D.

Professor and Director

Kinesiology Program

Curry School of Education

Dr. Phil’s UltimateWeight Solution

TheSouth BeachDiet

Dr. Atkin’sNew DietRevolution

SugarBusters!

Enter the ZoneProtein Power

Pritikin

Ornish

Glucose Revolution

Good Carbs? Bad Carbs? No Carbs?

High Glycemic?

Low Glycemic?

Cause of obesity?

Calorie Myths

• Can “bad carbs” be good?

• Can exercise make you fatter?

• Can being “overweight” be a sign of good health

The Calorie Conundrum• Intense focus on weight (loss)

• Prevalence of weight loss attempts at all-time time

• Diet industry ~ $35 billion/year

• Exercise programs mainly geared to “burn fat”

Google Search:Weight Loss Options

Key words Hits

• “fat burning exercise” 42,300

• “fat burning foods” 167,000

• “permanent weight loss” 376,000• “six-pack abs” 573,000

How many Abdominal Crunches does it take to burn one pound of fat?

a. 250

b. 2,500

c. 25,000

d. 250,000

How many Abdominal Crunches does it take to burn one pound of fat?

a. 250

b. 2,500

c. 25,000

d. 250,000

Measuring Calorie Burning During Exercise

What About Exercise?

• Burns Calories

• Reduces Body Fat

• Adds Muscle

Replacing 1 Pound of Fat with 1 Pound of Muscle will Burn how Many

Extra Calories each Day?

a. 5

b. 50

c. 75

d. 100

Replacing 1 Pound of Fat with 1 Pound of Muscle will Burn how Many

Extra Calories each Day?

a. 5

b. 50

c. 75

d. 100

Does Exercise Reduce Body Fat?

--Population Studies

--Exercise Intervention Studies

2021222324252627282930

0 1 2 3 4 5

Physical Activity Level

Bo

dy

Ma

ss

Ind

ex

. NHS

NHS (Post)

Finnish

IWHS

Copenhagen

German

Tromso

Association Between Physical Activity Level and Body Mass Index Among Women

22

23

24

25

26

27

28

29

0 1 2 3 4 5

Physical Activity Level

Bo

dy

Ma

ss

Ind

ex

. HPFS

Whitehall

Finnish

Copenhagen

German

Tromso

Zutphen

Goteborg

Association Between Physical Activity and Body Mass Index Among Men

Donnelly et al, Exerc Sport Sci Rev, 33: 169-174, 2005

Change in Body Fat Mass Following Aerobic Exercise Training in Obese Women

-10

-5

0

5

10

Fat

Mas

s C

hang

e (k

g)

Subjects

“Losers” (N = 20)

“Gainers” (N=11)

Larmarche et al., Metabolism, 41: 1249-1256, 1992

Cha

nge

in b

ody

fat (

kg)

Cha

nge

in b

ody

fat (

kg)

Up to one-half of women will not lose a single pound of body fat with

exercise….

Up to one-third of women will actually gain body fat as a result of

exercise.

Change in BMI Over 10-year Follow-up in Active and Inactive Older Persons

2021222324252627282930

Active Inactive

Bod

y M

ass

Inde

x

.1987 1997

Petrella et al., Diabetes Care, 2005; 28: 694-701

Dr. Phil’s UltimateWeight Solution

TheSouth BeachDiet

Dr. Atkin’sNew DietRevolution

SugarBusters!

Enter the ZoneProtein Power

Pritikin

Ornish

Glucose Revolution

Prevalence of Obesity and Weight Loss Attempts1960’s – 2000’s

0

10

20

30

40

1960's 1980's 1990's 2000's

% o

f U

.S. A

dults

.

Obesity

Wt Loss Attempt

Major Predictor of Future Weight Gain and Obesity Risk

Frequent Weight Loss Attempts!

Carbohydrate Phobia

Are Carbs bad?

“Shape of the Future:R. Atkins Diet”

--Newsweek

“Atkins Diet:Is It Safe?”

--McCall’s

“Risks in the new low-carbohydrate

diet”

--Reader’s Digest

“Shape of the Future:R. Atkins Diet”

--Newsweek

1975

“Atkins Diet:Is It Safe?”

--McCall’s1973

“Risks in the new low-carbohydrate

diet”

--Reader’s Digest

1965

Déjà vuall over again?

The So-called“Low-Fat” Phase

of the American Diet1980s – 1990s

Carbohydrate Intake (Percent of Total Kcal)NHANES 1971 – 2000

30

35

40

45

50

55

1971-1974 1976-1980 1988-1994 1999-2000

Inta

ke (

Per

cen

t)

Men

Women

MMWR (2004), 53(04): 80-82

“Low Fat” Years

Fat Intake (Percent of Total Kcal)NHANES 1971 – 2000

20

25

30

35

40

45

1971-1974 1976-1980 1988-1994 1999-2000

Inta

ke (P

erce

nt)

Men

Women

MMWR (2004), 53(04): 80-82

“Low Fat” Years

Did we really go“low fat?”

Fat Intake (Grams/day)NHANES 1971 – 2000

0

20

40

60

80

100

120

1971-1974 1976-1980 1988-1994 1999-2000

Inta

ke (

Gra

ms/

day

)

Men

Women

“Low Fat” Years

MMWR (2004), 53(04): 80-82

Energy Intake, 1971 – 2000 [NHANES]

2618266624392450

1877179815221542

0

500

1000

1500

2000

2500

3000

1971-1974 1976-1980 1988-1994 1999-2000

Inta

ke (

Kca

l/day

)

Men

Women

MMWR (2004), 53(04): 80-82

“Low fat” years

“Low-fat” was a myth

The “low-fat” period of the American diet was, in reality,

HIGH CALORIE

Calories do Count

22

23

24

25

26

27

28

25 35 45 55 65

Carbohydrate (% of total)

Body

Mass

Index

.

NHANES (men)

NHANES (women)

CSFII (men)

CSFII (women)

WHS

NHS I

NHS II

HPFS

Association between CARBOHYDRATE intakeand BODY MASS INDEX

Adapted from: Gaesser, J. Am. Dietetic Assoc., in press

22

23

24

25

26

27

28

29

30

75 125 175 225

Glycemic Load

Body

Mass

Index

.

NHS I

NHS II

WHS

HPFS

Swedish (SMC)

Canadian NBSS

Association between GLYCEMIC LOADand BODY MASS INDEX

Adapted from: Gaesser, J. Am. Dietetic Assoc., in press

22

23

24

25

26

27

28

29

30

25 35 45 55 65 75 85 95

Glycemic Index

Body

Mass

Index

. NHS I

NHS II

WHS

HPFS

ARIC (Whites)

ARIC (Blacks)

Zutphen

Melbourne CCS

Canadian NBSS

Japan (JMETS)

Association between GLYCEMIC INDEXand BODY MASS INDEX

Adapted from: Gaesser, J. Am. Dietetic Assoc., in press

It’s the Calories,Not the Carbs

Is Overweight really a health problem?

Body Weight and Health

“Just a few extra pounds could mean fewer years”

--Washington Post, August 23, 2006

NIH-AARPDiet and Health Study

“Overweight, obesity, and mortality in a large prospective cohort of persons 50 to 71

years old”

New Engl J Med 2006; 355: 763-778

Authors’ Conclusion

“Excess body weight during midlife, including overweight, is associated with an increased

risk of death.”

NIH-AARP Diet and Health Study

• 3+ million surveys sent out in 1995/96• 567,169 returned (~18% return rate)• 527,265 used in main data analysis• 10-year follow-up• Main conclusion based 111,081 (21% of

those returned; <4% of surveys mailed) men and women who never smoked and provided information on “recalled weight” at age 50

BMI Standards

• <18.5 Underweight

• 18.5-24.9 Normal Weight

• 25.0-29.9 Overweight

• >30 Obese

BMI Category Associated with the Lowest, and Highest, Relative Risk For Mortality - Men

Variable Lowest risk BMI category* Highest risk BMI category*

Overall Overweight UnderweightWhite Overweight UnderweightBlack Overweight UnderweightHispanic Overweight ObeseAsian, Pac Island, NA Overweight ObeseAge 50-55 Overweight UnderweightAge 56-60 Overweight UnderweightAge 61-65 Overweight UnderweightAge 66-71 Overweight UnderweightSmoker Overweight UnderweightFormer smoker Overweight UnderweightNever smoked Overweight ObesePreexisting chronic disease Overweight UnderweightNo preexisting disease Overweight ObeseFollow-up <5 years Overweight UnderweightFollow-up >5 years Overweight ObeseBMI at age 50** Normal ObeseBMI at age 50, never smoked Normal Obese

BMI Category Associated with the Lowest, and Highest, Relative Risk For Mortality - Women

Variable Lowest risk BMI category* Highest risk BMI category*Overall Normal = Overweight UnderweightWhite Normal = Overweight UnderweightBlack Overweight UnderweightHispanic Normal ObeseAsian, Pac Island, NA Normal ObeseAge 50-55 Overweight UnderweightAge 56-60 Normal ObeseAge 61-65 Overweight UnderweightAge 66-71 Normal UnderweightSmoker Overweight UnderweightFormer smoker Normal = Overweight UnderweightNever smoked Normal ObesePreexisting chronic disease Overweight UnderweightNo preexisting disease Normal ObeseFollow-up <5 years Normal UnderweightFollow-up >5 years Overweight ObeseBMI at age 50** Normal ObeseBMI at age 50, never smoked Normal Obese

Authors’ Conclusion

“Excess body weight during midlife, including overweight, is associated with an increased

risk of death.”

This conclusion is based on results from 21% of the sample population

Results from the other 79% of the sample population do not support this

conclusion

Body Weight and Health

“Some Extra Heft May be Helpful, New Study Finds.”

--New York Times, April 20, 2005

All-Cause Mortality, Relative RiskNHANES I, II, III [Ages 25-59]

0.0

0.5

1.0

1.5

2.0

<18.5 18.5-25 25.0-30 30-35 >35

Flegal et al., JAMA 293: 1861-1867, 2005

Rel

ativ

e R

isk

BMI

“The idea that a given body weight, or percentage body fat, is a

meaningful indicator of health, fitness, or prospects for longevity is

one of our most firmly held beliefs—and one of our most dubious

propositions.”

--G. Gaesser, Big Fat Lies, 1996

What does it all mean?

• Health benefits of regular exercise are INDEPENDENT of changes in body weight, or loss of body fat

• Health benefits of healthy eating are INDEPENDENT of changes in body weight, or loss of body fat

Exercise

• 30 minutes of moderate-intensity activity,

5 days per week

OR:

• 20 minutes of vigorous-intensity activity,

3 days per week

AND:

• ~2 days per week of strengthening exercises

Diet

• Choose whole-grain, fiber-rich foods

• Fruits, vegetables

• Reduce intake of saturated and trans fats

• No need to count calories

Enjoy the Game!