Energy Balance and Weight Management – Chapters 8 and 9
ENERGY IN
Regulation of food intake:
Hunger
Satiation
Satiety
Appetite
ENERGY OUT
Basal Metabolism
Factors that affect BMR
Energy expenditure for physical activity:
Depends on the activity duration, type, and intensity
Also affected by body size and fitness level
NEAT is the energy associated with unintentional activities like fidgeting, maintenance of posture, or spontaneous muscle contraction
Energy expenditure to process food:
Thermic effect of food (TEF) – the energy used to digest, absorb, and metabolize energy-yielding food
TEF is lower for fat than for carbohydrate and protein
TEF peaks one hour after eating, and normally dissipates within 5 hours
Accounts for ~10% of total energy expenditure
MEASUREMENT of ENERGY EXPENDITURE
Estimating energy expenditure: EER calculation (page 257)
BODY COMPOSITION
Assessing body weight:
weight tables
body mass index (BMI) = weight (kg)/height (m2)
BODY FAT DISTRIBUTION
gynoid obesity (pear-shaped figure), more common in women
android obesity (apple-shaped figure), more common in men
–increases risk of heart disease and diabetes mellitus
ENERGY IMBALANCE: Overweight and Obesity
Health risks (page 265)
Prevalence of overweight and obesity – it is a worldwide public health problem. We are now seeing an obesity epidemic in children as well as adults.
OBESITY in our CHILDREN
NationalCenter for Health Statistics suggests nearly 25% of children are overweight or obese
There are now about 5 million obese children in the United States – up by 50% since 1991
A 1999 Survey of Seattle High Schools showed that:
9% of males and 6% of females were overweight
HEALTH CONSEQUENCES
Overweight children and adolescents are more likely to become overweight or obese adults
Type 2 diabetes, high blood lipids, hypertension, early maturation and orthopedic problems also occur with increased frequency in overweight youth
ECONOMIC CONSEQUENCES
In 2000, the total cost of obesity was estimated to be $117 billion
Most of the cost associated with obesity is due to type 2 diabetes, coronary heart disease, and hypertension
WHAT CAUSES OBESITY?
WEIGHT MANAGEMENT- What Works???
Unfortunately, there is no magic pill, no perfect diet. The simple fact is, if you consume more calories than you burn, you will gain weight
A slow weight loss (1-2 pounds per week) is the best way
To lose 1 pound of fat, you must burn an extra 3500 calories (in one week that = 500 calories per day)
Important Components:
–Diet composition
–Physical activity
–Behavioral change
–Balancing acceptance and change
–Support!
DIET COMPOSITION
A Healthful Eating Plan Involves:
–Realistic energy intake
–Nutritional adequacy
–Small portions, small frequent meals
–Reduced simple sugar and alcohol intake
–Adequate water
–Physical activity!
PHYSICAL ACTIVITY
Contributions to weight loss and maintenance:
–Direct increases in energy output (muscles and cardiovascular system)
–Indirect energy output (elevated BMR)
–Appetite control
–Psychological benefits
Note: Spot reducing is not possible
BEHAVIORAL CHANGE
Behavior modification: the changing of behavior by the manipulation of antecedents (cues or environmental factors that trigger behavior), the behavior itself, and consequences (the penalties or rewards attached to behavior).
SUPPORT
•Family
•Friends
•Weight Loss Support Groups
WEIGHT MANAGEMENT
Adjuncts to treatment
–Drugs
–Self-help activities
–Commercial programs
–Professional private counselors
–Surgery: gastric banding, gastric bypass
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