1. Kin 110 Lecture 9
Ch. 9 Weight Control

2. Energy Balance and Imbalance
Weight Control Overview
Energy Balance
What drives us to eat and participate in activity
Indices for body composition assessment
Fat distribution and health concerns
healthful approaches to weight loss

3. Energy Balance Fig 9-1, p 311 Positive Energy Balance
Negative Energy Balance
Maintaining balance is important health goal for the prevention of many diseases
Energy Intake (macromolecules)
convenience
energy content of a meal
Calorimeter
1 kcal - energy to raise 1 kg of water 1 degree Celsius

4. Energy Use Basal Metabolism (BMR)
% of total energy used by body
minimal energy needed to keep awake resting body alive
varies 25-30% between people
Liver, Muscle/Brain, heart, kidneys (in order of energy utilized at rest)
~1 kcal/Kg/hour, influenced by:
lean body mass and surface area,
Age, (declines 2% per decade)
nervous and hormonal activity,
nutritional state, pregnancy
caffeine and tobacco use
low energy intake - decrease BMR

5. Energy Use Physical Activity (variable)
can increase energy expenditure %
many choices available :
take stairs, walk to corner store, *increase movement*
Thermic effect of food
(5-10 %) of total intake
digestion, absorption, process

6. Energy Use Adaptive Thermogenesis (7%) overfeeding and shivering
brown adipose tissue
Measurement of Energy Use
Calorimeter
direct / indirect
Estimates by weight, degree of physical activity and age

7. Estimating Energy Needs
Sedentary - 20 kcal/Kg
Light Activity - 30 kcal/Kg
Heavy Activity - 45 kcal/Kg
Estimates per day
1600 kcal/day
sedentary women, older adults
2200 kcal/day
active women, men
2800 kcal/day
v. active women, active men,

8. Food Intake Hunger - physiological drive to eat
controlled by internal body mechanisms
Appetite - psychological drive to eat, external stimulus
Satiety - state in which there is no longer the desire to eat

9. Estimating Healthy Weight
Most are based on large population data,
general guides not intended for individual application
Family History of obesity related conditions is very important
High BP, LDL, Glucose,
obesity, heart disease, cancer
Important to make individual estimate of healthy weight
what weight you maintained as an adult for one year without significant hunger
Be realistic healthy lifestyle is most important

10. Healthy Weight Body Mass Index (BMI) Table 9-1, p. 318
body weight/height*height
health risk with BMI over 25
over fat or overweight???
Metropolitan Life Tables
longevity not health, limited population inclusion

11. Energy Imbalance Energy intake exceeds output can lead to obesity
Obesity - excess body fat
BMI over 30, weighing 20 % more that healthy weight
Health problems Table 9-2, p.319
Over Fat
males 25 %, females 30-35%
BMI over 40 sever health risk
Underwater weighing,Skin Folds, Bio-electrical impedance

12. Fat Distribution Fig 9-7, p 322 Upper body obesity
heart disease, high blood pressure, diabetes
testosterone and alcohol
lower body obesity requires about 20 lbs more for same health risk
90 % are mildly obese in USA
juvenile onset, increased risk
10 % loss for “healthier weight”

13. Why ?? Many factors both genetic and psychological are influential
Identical twins
genes determine metabolic rates and brain chemistry
Body Types
ectomorph, mesomorph, endomorph
differences in met. , surface area
“Thrifty metabolism”

14. Environmental Influence
Family eating patterns or genetics ?
Little change in gene pool, but increase in obesity
Table 9-3, p. 326

15. Treatment of Obesity Number 2 health risk in US after smoking
chronic disease
treatment is long term lifestyle change
as with diabetes and high BP, need to have healthy active living with appropriate dietary modifications

16. 5 Principles of Treatment
Goals of dieting misdirected
be realistic, most under BMI of 25
focus on healthy active lifestyle and maintenance of body weight
Body defends itself against weight loss
basal metabolism drops
increased efficiency of fat storage
Weight Cycling is Common
5% maintain loss, others gain more, increased health risk

17. Principles Weight gain in adulthood is common
Focus on changing Body Composition
loss should be from adipose not lean tissue
rapid loss is fluid and lean mass
only highly motivated should attempt weight loss
begin with maintenance, and awareness of eating habits and physical activity patterns

18. Weight Loss Guidelines
Table 9-4, p 331
Control energy intake, increase expenditure, acknowledge that lifelong change is necessary
Rate of Loss
slow weight loss 1-2 Lb per week
maintenance for a few months following 10 % reduction
Flexibility
participate in normal activities
Individual taste and habits

19. Weight loss Guidelines
Intake
meet nutritional needs
minimum kcal /day
reduce hunger and fatigue
choose common foods
Behavior Modification
lifetime focus to maintenance of healthy lifestyle
changes are reasonable
Overall Health
Should consult physician if :
existing health problems, (over 35) or plan to lose weight very quickly
regular activity, rest, stress reduction
address underlying psychological issues

20. Controlling Intake
Estimate requirements and reduce by ~ 400 kcal / week
count fat (g) not entire diet
focus on naturally low fat foods rather than fat reduced
use exchange system (Appendix c)
reduce fat but increase bulk
complex carbohydrates, fiber
stick to food guide, reduce high fat foods
Table 9-5, p 333

21. Physical Activity Regular activity has many benefits
200 kcal expenditure
walking for 1 hour
cycling for 30 min
swimming for 20 min
running for 15 min
Lifestyle change - activity habits and daily routine
quick walks, stairs, fidgeting
Table 9-6,. P 334

22. Behavior Modification
Lifestyle changes
food intake and activity
Chain Breaking
breaking link between behaviors that encourage overeating/inactivity
Stimulus control
altering environment
Cognitive restructuring
changing frame of mind regarding eating

23. Behavior Modification
Contingency Management
forming plans of action to respond to potential overeating situations
Self Monitoring
tracking of foods and conditions affecting choices
Table 9-7, p. 336
lists many helpful behaviors
Prevent lapse, relapse
positive framing, social support