Weight Loss Energy balance o When looking to gain or lose weight you must look at the 1st law of thermodynamics energy is neither created or destroyed o All changes in weight can be described as a mass and energy balance o Calories in Calories out weight gained or lost o Calories gained are stored primarily as fat 3500 kcal per pound of fat Calories out o Caloric expenditure BMR activity o Basal metabolic rate BMR calories burned when at rest Measured by heat giving off at rest Affected by Age Gender Body composition Drugs Increased with exercise Decreases with age Males are more efficient than females Medications to increase BMR Calories in o 3500 kcal required to gain or lose 1 lb of fat fat 9 kcal g carb 4 kcal g protein 4 kcal g o Most important part of weight loss is total calories o Some diet aids work by interfering with digestion of certain food components in an attempt to allow you to consume but not absorb calories Body resists change o Every organism needs to be able to acquire and store energy o If an organism looses weight it senses that if it continues they will die o An adaptable organism will try to reduce energy usage or become o If appetite receptors are blocked body makes more receptors to over more efficient come perceived threat Diet plans include o Behavior modification o Calorie reduction o Physical activity o Psychological support o Medical supervision Diet aids o May contain Phenylpropanolamine an amphetamine like appetite suppressant banned Fiber containing pills Anesthetic Sugar containing pills