Energy Balance and Weight Control

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Energy Balance and Weight Control

• Dr. David L. Gee
• FCSN 245-Basic Nutrition

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Energy Balance

• EB E(in) - E(out)
• E(in) dietary intake of energy
• E(out) energy expenditure

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Energy BalanceThe Key to Weight Change

• When E(in) lt E(out)
• Negative energy balance
• weight loss
• When E(in) gt E(out)
• Positive energy balance
• weight gain
• When E(in) E(out)
• Zero energy balance
• no weight change

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How do you measureEnergy (in)

• Calories
• energy required to heat 1 kg water by 1 degree C.
• Bomb Calorimeter

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How do you measure E(out)

• Direct Calorimetry
• measures heat directly
• bomb calorimeter (for food)
• room calorimeter
• Indirect Calorimetry
• measures oxygen consumed or
• carbon dioxide produced

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The effects of energy imbalance are cumulative!!

• If EB of 100 Cal/day
• EB of 36,500 Cal/year
• If 1 lb fat 3500 Cal
• Then see wt gain of 10 lbs per year !!!
• Therefore, knowing what affects energy balance is
  important
• Small consistent daily changes accumulate to
  large weight changes

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Energy Out

• Components of E(out)
• Basal Metabolic Rate (BMR)
• Activity (Act)
• Thermic Effect of Food (TEF)
• E(out) BMR Act TEF

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Basal Metabolic Rate

• Energy essential for life support
• Circulation
• Respiration
• Temperature Maintenance
• Nerve Transmission
• Kidney Function, etc

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Basal Metabolic Rate

• Estimation of BMR
• BMR 0.9 - 1 Cal / kg BW / hr
• Example
• 120 lbs / 2.2 lbs/kg 55 kg
• BMR 55 x 1 x 24hr/d
• BMR 1320 Cal / day

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Basal Metabolic Rate

• Factors affecting BMR
• Age
• Height
• Growth
• Body Composition

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Basal Metabolic Rate

• Factors affecting BMR
• Fever
• Stress
• Undernutrition

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Energy for Activity

• Sedentary (adds 25-35 of BMR)
• Light (35-50)
• Moderate (50-70)
• Heavy (gt70)
• Example
• Light Activity 40 x 1320 530 Cal
• Moderate Activity 60x1320 790 Cal
• Sedentary 30x1320 396 Cal
• Mod to Sed 41 pounds of fat per year!!

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Thermic Effect of Food

• Increased energy expenditure after a meal.
• 5-10 of BMR
• Cost of digestion, absorption, assimilation of
  nutrients
• Ex 5 x 1320 60 Cal

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Estimation of E(out)

• E(out) BMR Act TEF
• Example
• E(out) 1320 530 60 1910 Cal
• BMR 69 of E(out)
• Act 28 of E(out)
• TEF 3 of E(out)

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Healthy Weight and the Non-Diet Approach

• David L. Gee, PhD
• Professor of Food Science and Nutrition
• Central Washington University

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Prevalence of Overweight in the US

• 1990 56 of Americans were overweight
• 23 were obese
• 2000 64 of Americans were overweight
• 30 were obese
• At this rate
• In 2010 73 overweight
• In 2020 84 overweight
• In 2030 96 overweight
• Increases in overweight/obesity were seen in
• Both males and females
• All age groups
• All ethnic groups

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The increase in prevalence in people with BMI gt
25 was almost Entirely due to increased
prevalence of obese!!! Overweight may be a
transitional state for most Americans !!!
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Ethnicity and Overweight (BMIgt27.5) Prevalence
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Epidemic Increase in Childhood Overweight,
1986-1998JAMA 2862845-2848 (2001)

• National Longitudinal Survey of Youth
• 1986-1998
• 8,270 children, aged 4-12 yrs
• Prior studies show it took 30 years for
  overweight prevalence to double. Current study
  show doubling time to be less than 12 years.
• Rate of increase particularly high in African
  American and Hispanic children

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Prevalence of Overweight Children in the US
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Epidemic Increase in Childhood Overweight,
1986-1998JAMA 2862845-2848 (2001)
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Prevalence of overweight in children.

• CDC (2004)
• Overweight above the 95th percentile for BMI
  based on NHANES II data from 1970s
• For adolescents 12-19 yrs
• 1974 7.4
• 2002 15.6

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Genes/Biology vs Environment

• Overweight is a result of both
• Adoption studies (biology)
• Adopted adults have BMI that are more similar to
  biological parents than to adoptive parents.
• Animal studies (biology)
• genetically obese rats and mice

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Genes/Biology vs Environment (cont.)

• Migration studies (environment)
• Japanese
• Hawaiian Japanese
• Californian Japanese
• Dietary Change Studies (biology and environment)
• SW Native Americans

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Pima Indians

• Mexican Pima Indians
• subsistence farming ranching
• 20 fat diet, 40 hrs/wk physical work
• Arizona Pima Indians
• mechanized agriculture, sedentary lifestyle
• 40 fat diet

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Pima Indians

• Arizona Pima Indians are
• 1 inch taller
• 57 pounds heavier
• 70 obese
• 50 with diabetes by age 35

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Genes vs Environment Conclusions

• Genes for weight gain predisposes some
  individuals towards weight gain.
• Environment determines which of those individuals
  actually gain weight.

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Why lose weight?

• Obesity is associated with greater risk of
• Diabetes
• Hypertension stroke
• Coronary heart disease
• Most cancers (except lung cancer)
• Sleep apnea, arthritis, gall stones, .
• Overfat vs Underfit ????
• Good question
• Vast majority of overfat are underfit

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Obesity and Causes of Death in the US
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The Obesity Epidemic in AmericaWhos
responsible?

• Personal responsibility
• Environmental influences
• Do we need a Food Police?
• http//www.nytimes.com/2005/06/12/business/yourmon
  ey/12food.html?pagewanted1

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What is a Healthy Weight?

• A broad range of weight which allows for minimal
  risks for chronic diseases.
• Goes beyond using only body weight as a criteria
  for good health.

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Determination of your "healthy weight".

• Step 1. Body Mass Index
• BMI BW(kg)/Ht2(m2)
• Dr. Phil
• from Nutrition Action Health Letter, Jan. 2004
• 64" 78" x 0.0254(m/in) 1.93m
• 240lbs / 2.2(lb/kg) 109kg
• BMI 109/(1.932)109/3.72
• 29.3

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BMI Classifications

• BMI 19 - 25 gt Desirable
• BMI 25 - 30 gt Overweight
• BMI 30 - 35 gt Obese, category 1
• BMI 35 - 40 gt Obese, category 2
• BMI gt 40 gt Severe obesity
• Healthy weight is a broad range of weight
• For 510, BMI 19-25
• 132 174 lbs

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BMI and Mortality Risk
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Healthy Weight (cont.)

• If your BMI gt 25, then consider presence of other
  health risk factors.

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Healthy Weight (cont.)

• Body Fat Distribution
• upper body fatness associated with higher health
  risks
• Waist Circumference (1998 NIH)
• gt 35 for females,
• gt 40 for males

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Healthy Weight (cont.)Know your blood lipids!

• Hyperlipidemia/dyslipidemia
• TC gt 240 mg/dl
• LDL-C gt 160 mg/dl
• HDL-C lt 40 mg/dl
• TG gt 200 mg/dl

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Healthy Weight (cont.)Know your blood pressure!

• High Blood Pressure
• Systolic BP gt 140 mm Hg or
• Diastolic BP gt 90 mm Hg or
• Borderline or Pre-hypertensive
• gt130/85

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Healthy Weight (cont.)Know your blood sugar and
history

• Hyperglycemia (Diabetes)
• Fasting Blood Glucose
• gt 126 mg/dl
• Impaired Glucose Tolerance
• Pre-diabetic
• gt110 mg/dl
• Gestational Diabetes
• Family History of Diabetes

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Healthy Weight Summary

• If your BMI is 19-25, you are at a Healthy
  Weight.
• Health problems are not weight related
• If your BMI is gt 25 and you have no other risk
  factors, you are at a Healthy Weight.
• If your BMI is gt 25 and you have one or more risk
  factors, you are NOT at a Healthy Weight.
• Weight loss is likely to improve your health

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Should everybody who is overweight try to lose
weight?Will weight loss improve your quality of
life?A Prospective Study of Weight Change and
Health-Related Quality of Life in Women

• JAMA Dec. 1999
• Nurses Health Study
• 40,098 women, 4 yr longitudinal study
• Weight changes
• Quality of life questionnaire
• Physical function
• Vitality
• Freedom from bodily pain
• Mental health

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The effect of weight gain/loss onVitality Score

• Weight gain
• associated with declines in vitality scores in
  all BMI categories
• Weight loss
• associated with improved vitality scores only in
  women with BMIgt25

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The effect of weight gain/loss onMental Health
Score

• Weight gain
• associated with a decline in mental health scores
  in all weight categories
• Weight loss
• associated with improved mental health scores
  only in obese class I women and declined in
  normal weight women.

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A Prospective Study of Weight Change and
Health-Related Quality of Life in
Women.Conclusions

• For women at all BMI categories
• Dont gain weight
• Reduced quality of life
• For overweight and obese women
• Weight loss is generally associated with improved
  quality of life
• For normal weight women
• Weight loss does not improve quality of life
• May actually reduce quality of life

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Do media images affect your idea of what you
should look like? 2000 Grammy Awards
Do media images actually Contribute to weight
problems?
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Bottom Line on Weight Loss

• Lose weight for the right reasons
• Improve health and your quality of life
• Losing weight to attain the perfect body
• May lead to frustration
• And, ironically, weight gain
• May lead to eating disorders

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Dietary Means to a Healthy Weight

• Weight loss occurs when in negative energy
  balance
• Weight loss is only half the battle
• Maintenance of weight loss is the critical problem

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Dietary Means to a Healthy WeightBalanced
Reduced Calorie Diet

• Characteristics
• Calories reduced by 500-1000 Cal/day
• CHOPROFAT 50-60 10-15 20-30
• Examples
• Weight Watchers, Jenny Craig, Slim Fast
• What the research shows
• Short-term outcomes
• Modest weight loss, improved health
• Long-term outcomes
• Success rate not great

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Dietary Means to a Healthy WeightLow
Carbohydrate Diets

• Characteristics
• Very low in CHO
• Restricted intakes of fruit, cereals, pasta,
  bread, potatoes, rice
• Caloric intake not specified
• Examples
• Atkins diet
• What the research shows
• Short-term outcomes
• 6 month studies, good weight loss, no substantial
  change in heart disease risk factor, drop-out
  rate significant
• Long-term outcomes
• No long term studies, health risks?, 1 yr studies
  show more weight regain compared to low-fat diets

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Dietary Means to a Healthy WeightThe
Carbohydrate Restrained Diets

• Characteristics
• Lower in CHO than Dietary Guidelines but higher
  than Low Carb diets (40 CHO, 30FAT, 30PRO)
• Low glycemic index foods encouraged
• Monounsaturated fats encouraged
• Examples
• Zone Diet, South Beach Diet
• What the research shows
• Little research available on these diets

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Dietary Means to a Healthy WeightHealthy
Diet/Non-Diet Approach

• Characteristics
• Focus on quality of the diet, not quantity
• Attaining good health is primary goal, not weight
  loss
• Examples
• DASH diet, Dietary Guidelines, Food Guide Pyramid
• What the research shows
• Short-term outcomes
• Slow, limited weight loss, health benefits
• Long-term outcomes
• U. Colorados Weight Loss Registry
• Diet most adopt in order to maintain weight loss

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Exercise and Weight Loss

• U. Colorados Weight Loss Registry
• Exercised used by nearly 100
• Walking the most common form of exercise
• Benefits of Exercise
• Rate of weight loss greater
• Caloric restriction not as great
• Quality of weight loss better
• Proactive choice vs dieting
• Health benefits independent of weight loss

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Rates of physical inactivity in the US
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Exercise and Weight LossStructured Exercise

• Aerobic Exercise
• Burns more calories, more fat
• Stress duration initially
• Strength Training
• Builds more lean tissue
• Increases basal metabolic rate

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Exercise for Weight LossWalking vs
RunningGoing 4 miles
Walking _at_ 15min/mile Jogging _at_ 8 min/mile
Calories burned 400 Cal 400 Cal
Fuels burned CHOFAT 5050 7525
Calories CHO 200 Cal 300 Cal
Calories FAT 200 Cal 100 Cal
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Exercise for Weight LossWalking vs
RunningGoing 1 hour
Walking _at_ 15min/mile Jogging _at_ 8 min/mile
Distance covered 4 miles 7.5 miles
Calories burned 400 Calories 750 Calories
Fuels burned CHOFAT 5050 7525
Calories CHO 200 Calories 560 Calories
Calories FAT 200 Calories 190 Calories
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Exercise for Weight LossWalking vs Running

• Conclusions
• Walking and running burn the same number of
  calories over the same distance
• Walking burns more fat than running over the same
  distance
• Running burns calories at a faster rate and
  improves cardiovascular fitness more.
• Bottom line Just do it!
• Either type of exercise is beneficial

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Exercise and Weight LossStructured Exercise

• Characteristics of Successful Programs
• Convenient
• Enjoyable
• Safe
• affordable
• Subject realizes net benefit over costs

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Exercise and Weight LossLifestyle Activity

• 24 hr day
• Sleep/rest 10 hrs
• Structured exercise 1 hr
• What you do the remaining 13 hrs of the day?
• Burn extra 25 Cal/hr 325 Cal/day
• 33 pounds of fat loss per year
• Develop a new attitude about being active
• Pedometers and 10,000 step programs
• Health benefits significant

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Weight Loss/Weight MaintenanceBehavior/Attitude
Changes

• Pay attention to what you eat
• Success of weight loss programs
• Examine
• Triggers for eating
• Emotional eating
• Risky situations
• Behavior Modification Programs
• Track/record eating behaviors
• Identifies problems
• Sets goals and establishes rewards
• Continual reassessment/problem solving

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For more severe weight loss

• Prescription Drugs
• For those with BMI gt 30 or
• For those with BMI gt27 and risk factors
• Meridia (Sibutramine, Abbott Lab)
• Suppresses appetite
• Increases brain serotonin norepinephrine levels
  signal for satiety
• Xenical (Orlistat, Roche)
• Inhibits fat absorption
• Reduces calories from fat containing foods
• Results in adverse reactions if eating high fat
  foods
• Long term success and risks
• Meridia hypertension
• Xenical steatorrhea (fatty diarrhea)

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For those with Severe Obesity

• Surgical Methods
• For those with BMI gt40

Carnie Wilson
Al Roker
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For those with Severe Obesity

• Gastroplasty
• Reduces size of stomach by banding or stapling
• Gastric Bypass Surgery
• Reduces size of stomach
• Bypasses much of the small intestine
• Outcomes
• Rapid and substantial weight loss
• Side effects
• Dangers