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Brain and Behavior: Obesity and Weight Control. Rena R. Wing, Ph.D. Professor of Psychiatry and Human Behavior Brown Medical School Director, Weight Control & Diabetes Research Center The Miriam Hospital. Brain & Behavior April 2005. Weight = Energy In – Energy Out. Accuracy: - PowerPoint PPT Presentation
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Rena R. Wing, Ph.D.Rena R. Wing, Ph.D.Professor of Psychiatry and Human BehaviorProfessor of Psychiatry and Human Behavior
Brown Medical SchoolBrown Medical SchoolDirector, Weight Control & Diabetes Research CenterDirector, Weight Control & Diabetes Research Center
The Miriam HospitalThe Miriam Hospital
Brain and Behavior:
Obesity and Weight Control
Brain & Behavior April 2005
Weight = Energy In – Energy Out
Accuracy:
•Energy intake in one year = 955,000 calories
•Gaining one pound in one year = 3,500 calories
•Error of 0.4% or 11 calories per day will produce a weight gain of one pound
Am J Physiol Gastrointest Liver Physiol 286: G7-G13, 2004; 10,1152/ajpgi. 00448.2003.
• Body Mass Index (BMI):Body Mass Index (BMI): kg / mkg / m22
weight in kilograms divided by height in meters squaredweight in kilograms divided by height in meters squared
• Obese: BMI Obese: BMI >> 30 30
• Body Mass Index (BMI):Body Mass Index (BMI): kg / mkg / m22
weight in kilograms divided by height in meters squaredweight in kilograms divided by height in meters squared
• Obese: BMI Obese: BMI >> 30 30
Obesity Trends Among U.S. Adults between 1985 and 2002
Obesity Trends Among U.S. Adults between 1985 and 2002
Obesity Trends* Among U.S. AdultsBRFSS, 1985
No Data <10% 10%–14%
(*BMI ≥30, or ~ 30 lbs overweight for 5’ 4” woman)
Obesity Trends* Among U.S. AdultsBRFSS, 1986
No Data <10% 10%–14%
(*BMI ≥30, or ~ 30 lbs overweight for 5’ 4” woman)
Obesity Trends* Among U.S. AdultsBRFSS, 1987
No Data <10% 10%–14%
(*BMI ≥30, or ~ 30 lbs overweight for 5’ 4” woman)
Obesity Trends* Among U.S. AdultsBRFSS, 1988
No Data <10% 10%–14%
(*BMI ≥30, or ~ 30 lbs overweight for 5’ 4” woman)
Obesity Trends* Among U.S. AdultsBRFSS, 1989
No Data <10% 10%–14%
(*BMI ≥30, or ~ 30 lbs overweight for 5’ 4” woman)
Obesity Trends* Among U.S. AdultsBRFSS, 1990
No Data <10% 10%–14%
(*BMI ≥30, or ~ 30 lbs overweight for 5’ 4” woman)
Obesity Trends* Among U.S. AdultsBRFSS, 1991
No Data <10% 10%–14% 15%–19%
(*BMI ≥30, or ~ 30 lbs overweight for 5’ 4” woman)
Obesity Trends* Among U.S. AdultsBRFSS, 1992
No Data <10% 10%–14% 15%–19%
(*BMI ≥30, or ~ 30 lbs overweight for 5’ 4” woman)
Obesity Trends* Among U.S. AdultsBRFSS, 1993
No Data <10% 10%–14% 15%–19%
(*BMI ≥30, or ~ 30 lbs overweight for 5’ 4” woman)
Obesity Trends* Among U.S. AdultsBRFSS, 1994
No Data <10% 10%–14% 15%–19%
(*BMI ≥30, or ~ 30 lbs overweight for 5’ 4” woman)
Obesity Trends* Among U.S. AdultsBRFSS, 1995
No Data <10% 10%–14% 15%–19%
(*BMI ≥30, or ~ 30 lbs overweight for 5’ 4” woman)
Obesity Trends* Among U.S. AdultsBRFSS, 1996
No Data <10% 10%–14% 15%–19%
(*BMI ≥30, or ~ 30 lbs overweight for 5’ 4” woman)
Obesity Trends* Among U.S. AdultsBRFSS, 1997
No Data <10% 10%–14% 15%–19% ≥20
(*BMI ≥30, or ~ 30 lbs overweight for 5’ 4” woman)
Obesity Trends* Among U.S. AdultsBRFSS, 1998
No Data <10% 10%–14% 15%–19% ≥20
(*BMI ≥30, or ~ 30 lbs overweight for 5’ 4” woman)
Obesity Trends* Among U.S. AdultsBRFSS, 1999
No Data <10% 10%–14% 15%–19% ≥20
(*BMI ≥30, or ~ 30 lbs overweight for 5’ 4” woman)
Obesity Trends* Among U.S. AdultsBRFSS, 2000
No Data <10% 10%–14% 15%–19% ≥20
(*BMI ≥30, or ~ 30 lbs overweight for 5’ 4” woman)
Obesity Trends* Among U.S. AdultsBRFSS, 2001
No Data <10% 10%–14% 15%–19% 20%–24% ≥25%
(*BMI ≥30, or ~ 30 lbs overweight for 5’ 4” woman)
Source: Behavioral Risk Factor Surveillance System, CDC
No Data <10% 10%–14% 15%–19% 20%–24% ≥25%
(*BMI ≥30, or ~ 30 lbs overweight for 5’ 4” woman)
Obesity Trends* Among U.S. AdultsBRFSS, 2002
Overweight & Obesity Overweight & Obesity in Rhode Island (2003)in Rhode Island (2003)
OverweightOverweight 38.5%38.5%
ObeseObese 18.4%18.4%
TOTALTOTAL 56.9%56.9%
Toxic Environment: Toxic Environment: Sedentary lifestylesSedentary lifestyles
• TelevisionTelevision
• ComputersComputers
• Cell phonesCell phones
• Remote controlsRemote controls
Physiological
Sociocultural
Individual/Behavioral
AAntecedents
BBehaviors
CConsequences
AAntecedents
BBehaviors
CConsequences
Low fat, Low Calorie Diet, Physical Activity
AAntecedents
BBehaviors
CConsequences
Low fat, Low Calorie Diet, Physical Activity
Stimulus Control
Changing Thoughts
and Feelings
Self-Monitoring, Goal-setting
Positive Reinforcers
Contingency
Contracts
Source of Calories
• Fat ………………Fat ……………… 9 calories/gram9 calories/gram
• Carbohydrates ….Carbohydrates …. 4 calories/gram4 calories/gram
• Protein ………….Protein …………. 4 calories/gram4 calories/gram
• Alcohol …………Alcohol ………… 7 calories/gram7 calories/gram
Low Calorie - Low Fat Diet Recommendations
Weight < 200 lbsWeight < 200 lbs
1000 - 12001000 - 1200
20 - 30%20 - 30%
22 - 4022 - 40
Weight > 200 lbsWeight > 200 lbs
1500 - 18001500 - 1800
20 - 30%20 - 30%
33 - 6033 - 60
Calories
Fat %
Fat (g)
Mean Percent Change in Weight among Subjects on the Low Carbohydrate Diet and Those on the Conventional Diet
Baseline Carried Forward Analysis
0
2
4
6
8
10
12
Cha
nge
in W
eigh
t (%
)
0 3 6 9 12Month
Low-carbohydrate diet
Conventional diet
* *
NEJM 348;21 2003
Weight Loss Maintenance Using Meal Replacements
0
2
4
6
8
10
12
Per
cen
tag
e re
du
ctio
n i
n i
nit
ial
wei
gh
t
Time (months)Ditschuneit et al., AJCN; 1999; 69: 198-204
Standard then Meal Replacement
Meal Replacement
0 2 4 6 8 10 12 14 16 18 20 22 24 26 28
Law of Thermodynamics
Resting Metabolic Rate (65%)Resting Metabolic Rate (65%)
Thermic Effect of Food (10%)Thermic Effect of Food (10%)
Exercise Exercise
(25%)(25%)
Food and liquid intakeFood and liquid intake
(100%)(100%)
Energy OutEnergy OutEnergy InEnergy In
1.1. Does exercise alone produce weight loss?Does exercise alone produce weight loss?
YesYes – but modest (2-4 kg) – but modest (2-4 kg)
• Does diet and exercise produce greater initial Does diet and exercise produce greater initial
weight loss than diet only?weight loss than diet only?
YesYes – but modest (2 kg) – but modest (2 kg)
• Does diet and exercise produce better long-Does diet and exercise produce better long-
term weight loss than diet only?term weight loss than diet only?
YesYes
Long Term Weight Loss
Study Diet Only Diet + ExercisePavlou 18 mo -3 -11Sikand 2 yr -0.8 -9.2Skendner 1 yr -6.8 -8.9
2 yr +0.9 -2.2Wadden 1 yr -15.3 -13.5
2 yr -6.9 -8.5Wing 1 yr -3.8 -7.9Wing 1 yr -5.5 -7.4
2 yr -2.1 -2.5
Physical Activity StrategiesPhysical Activity Strategies
• Short boutsShort bouts
• Home exerciseHome exercise
• Aerobic vs resistanceAerobic vs resistance
0
-2
-4
-6
-8
-10
-12
-14
-166 12 18
Cha
nge
in B
ody
Wei
ght,
kg <150 min/wk
>150 min/wk
>200 min/wk
Dose Response of Exercise on Weight Loss
Time, mo
AAntecedents
BBehaviors
CConsequences
Low fat, Low Calorie Diet, Physical Activity
Stimulus Control
Changing Thoughts
and Feelings
Self-Monitoring, Goal-setting
Positive Reinforcers
Contingency
Contracts
Modest Weight Loss Improves HealthModest Weight Loss Improves Health
•Improves glycemic control Improves glycemic control
•Improves cardiovascular risk factors Improves cardiovascular risk factors
•Improves psychological well-beingImproves psychological well-being
•Prevents or delays onset of type 2 diabetesPrevents or delays onset of type 2 diabetes
Diabetes Prevention ProgramDiabetes Prevention Program
• Over 3000 overweight adults with impaired Over 3000 overweight adults with impaired glucose toleranceglucose tolerance
• Randomly assigned to:Randomly assigned to:– Intensive lifestyle interventionIntensive lifestyle intervention
– MetforminMetformin
– PlaceboPlacebo
• Followed annually for over 3 yearsFollowed annually for over 3 years
Goal-based Behavioral InterventionGoal-based Behavioral Intervention
• An intensive program with the following An intensive program with the following
specific goals:specific goals:
>> 7% loss of body weight and maintenance 7% loss of body weight and maintenance
of weight lossof weight loss
>> 150 minutes/week of physical activity 150 minutes/week of physical activity
Lifestyle Intervention ResultsLifestyle Intervention Results
•Average activity = 225 minutes/weekAverage activity = 225 minutes/week
– 74 % met goal at week 2474 % met goal at week 24
–58% met goal at end of study58% met goal at end of study
•Average weight loss = 7% (7 kg or 14 lb) at Average weight loss = 7% (7 kg or 14 lb) at week 24 and 4% (4 kg or 8.8 lb) at end of week 24 and 4% (4 kg or 8.8 lb) at end of studystudy
–50% met 7% weight goal at week 2450% met 7% weight goal at week 24
–38% met 7% weight goal at end of study38% met 7% weight goal at end of study
-8
-6
-4
-2
0
0 1 2 3 4
Years from Randomization
Wei
ght C
hang
e (k
g)
Placebo
Metformin
Lifestyle
Mean Weight ChangeMean Weight Change
The DPP Research Group, NEJM 346:393-403, 2002
0 1 2 3 4
0
10
20
30
40Placebo (n=1082)Metformin (n=1073, p<0.001 vs. Plac)Lifestyle (n=1079, p<0.001 vs. Met , p<0.001 vs. Plac )
Percent developing diabetes
All participants
All participants
Years from randomization
Cum
ulat
ive
inci
denc
e (%
)Incidence of DiabetesIncidence of Diabetes
Risk reductionRisk reduction31% by metformin31% by metformin58% by lifestyle58% by lifestyle
BRFSS (1996) Data BRFSS (1996) Data BMI 25-27BMI 25-27
Physician Advised to Lose WeightPhysician Advised to Lose Weight
No ComorbiditiesNo Comorbidities 5.6%5.6%
Yes ComorbiditiesYes Comorbidities 13.6%13.6%
Trying to Lose WeightTrying to Lose Weight
If not advised If not advised 33.4%33.4%
If advisedIf advised 77.5%77.5%
National Weight Control Registry National Weight Control Registry (NWCR)(NWCR)
• Founded in 1993 by Drs. Rena Wing and James HillFounded in 1993 by Drs. Rena Wing and James Hill
• Registry of “successful losers”Registry of “successful losers”
• Minimum of 30 lbs of weight loss for a minimum of Minimum of 30 lbs of weight loss for a minimum of one yearone year
• >> 18 years of age 18 years of age
National Weight Control RegistryNational Weight Control Registry
• Over 4,000 members Over 4,000 members
• Weight loss averages 30 kgWeight loss averages 30 kg– 28.7 kg in women28.7 kg in women
– 35 kg in men35 kg in men
• Maintained the minimum weight loss (13.6 kg) for Maintained the minimum weight loss (13.6 kg) for
5.5 years5.5 years
• 16% maintained the minimum weight loss > 10 16% maintained the minimum weight loss > 10
yearsyears
NWCR: Maintenance StrategiesNWCR: Maintenance Strategies
• No similarity in how weight was lostNo similarity in how weight was lost
• Great similarity in how weight is being Great similarity in how weight is being
maintainedmaintained
– Low fat, low calorie dietLow fat, low calorie diet
– High daily levels of physical activityHigh daily levels of physical activity
– Frequent self-monitoringFrequent self-monitoring
Current Eating HabitsCurrent Eating Habits
• Average intake: 1380 kcalsAverage intake: 1380 kcals
• Average 24% fatAverage 24% fat
• Average 5 meals per dayAverage 5 meals per day
• Most eat breakfast dailyMost eat breakfast daily
• Eat out 3 meals/weekEat out 3 meals/week
• Very few follow an “Atkins” type of dietVery few follow an “Atkins” type of diet
Physical Activity in the NWCRPhysical Activity in the NWCR
• 91% report physical activity as an important 91% report physical activity as an important aspect of weight maintenanceaspect of weight maintenance
• Most NWCR members far exceeded the 150 Most NWCR members far exceeded the 150 minutes per week physical activity goal that is minutes per week physical activity goal that is recommended by the Surgeon Generalrecommended by the Surgeon General
• Average of 2600 calories per week of physical Average of 2600 calories per week of physical activity (equivalent to 1 hour per day)activity (equivalent to 1 hour per day)
CONCLUSION
• Modest weight loss improves health
• Most effective programs include low calorie/low fat diet, physical activity, and behavior modification
• Health-care providers are in a unique position to assess, advise, and reinforce weight loss efforts