Ch. 7-Weight Management
AMDR ranges that are tailored to needs and preferences of individual patient
*Carbohydrate*: 45-65% of total kcal intake *Protein*: 10-35% of total kcal intake *Fat*: 20-35% of total kcal intake
Other Proposed Genetic Causes
*Fat Cell Development*: -Amount of fat reflects both number and size of fat cells -Number of fat cells increases most rapidly during late childhood/early puberty -You can reduce the size, but not the number *Set-Point Theory*: -The body defends its weight via internal changes in BMR and hormones -Your "Set point" may be adjustable over time
Societal/Obesogenic Environmental Factors That Cause Obesity
*Genetic Effects are modified by environmental factors* -Technology/built environment -Availability of cheap, energy dense foods -Increasing portion size -Learned behavior
Proposed Genetic Cause: Dysregulation of enzymes/hormones
-*Lipoprotein Lipase*: promotes fat storage, high LPL activity in obese person -*Leptin*: signals the brain to decrease appetite & increase energy expenditure, obese may have "leptin resistance", increases thermogenesis -*Ghrelin*: signals brain to increase appetite and to store energy, levels increase after fasting in an effort to maintain weight
Physical Activity Guidelines
-150min/week of moderate-intensity physical activity or 75min/week of vigorous-intensity physical activity *NOTE: additional activity-at least 250min/week-is recommended for weight loss, fitness & more extensive health benefits*
Clinical Guidelines for Identifying a Person who should be Treated for Obesity
-BMI -Waist Circumference -Risk Status: Heart Disease, Type 2 Diabetes, sleep apnea ---Three of the following risk factors: HTN, smoking, HLD, low HDL, impaired glucose tolerance, over age 45 (M) or 55 (F), HD of immediate family member before age 55 (M) or 65 (F)
Who Should Be Considered for Surgical Treatments?
-BMI >40 or BMI >35 with co-morbidity -Unable to achieve and maintain a healthier body weight with non-surgical approaches -Has no significant mental health problems that would interfere with post-op compliance or may worsen after surgery -Is willing to make necessary lifestyle changes -Has strong social support system
Recommended weight loss based on BMI
-BMI of 27-35 -> 0.5-1.0 lb/week -BMI >35 -> 1.0-2.0 lb/week
Benefits of Physical Activity
-Contributes to energy deficit for weight loss -Helps minimize loss of lean body mass -Decreases BMR (immediately and long-term) -Decreases appetite in short-term -Decreases stress -Enhances psychological well-being
Evidence-Based Weight loss Recommendations
-Eat a low-calorie, moderately low-fat diet (500-1000 calories below your energy needs) --At least 1200 kcal (F) or 1600 kcal (M)
Weight Maintenance
-Eat a reduced-calorie diet -Include high-fiber foods (whole grains, fruits, veggies) -Drink water throughout the day! -Eat breakfast every day -Engage in 60min of physical activity daily (typically, walking) -Watch less than 10hrs of TV/week -Weigh regularly (once/week)
Strategies for Weight Gain
-Energy-dense foods and larger portions -3 meals + snacks at regular times -Plenty of caloric beverages (but not with meals) -Relaxed environment -Weight training to increase muscle mass
Genetic Factors That Cause Obesity
-Hormonal influences -# & size of fat cells -Body type -Resting metabolic rate
Obesity Drugs
-Only considered for those with BMI > or equal to 30 or BMI >or equal to 27 with risk factors -Only used in combo with diet & physical activity
Behavioral Factors That Cause Obesity
-Physical inactivity->technology/built environment -Chronic overeating -Sleep deprivation -Stress
Leading Cause of preventable death in the US?
-Smoking
Recommended amount of weight loss
10% in 6 months
Caloric deficit needed to lose 1lb/week
500 calorie deficit per day = 1lb loss/week
