Weight Management Flashcards
Body Weight and Body Composition: Defining healthy body weight
- what should be the primary focus of weight management efforts?
- The criterion of fashion: unrealistic ideals
- accepting a healthy body weight
- the criterion of health
- Obesity is a major chronic disease risk factor
- Range of healthy body weights the promote good health and longevity
Body Mass Index
- Weight in kg / height in m2 OR
- Weight in lb/ height in inches2 x 703
healthy weight
BMI 18.5 to 24.9
Underweight
BMI <18.5
Overweight
BMI 25.0 to 29.9
Obese =
BMI > 30
Body composition
- Diagnosis of overweight/obesity requires a BMI value plus some measure of body composition and fat distribution
- Central obesity
Visceral fat: fat stored within the abdominal cavity in association with abdominal organs - what are the health concerns associated with central obesity?
Central obesity
“Apple profile” of central obesity
- common in postmenopausal women and even more common in men
- Influential factors: smoking, alcohol consumption, and physical activity
“Pear profile” created by subcutaneous fat
Waist circumference
- Good indicator of fat distribution and central obesity
- High risk: > 35 inches for women or > 40 inches for men
Skinfold measures
- accurate estimate of total body fat and a fair assessment of the fat’s location
How much body fat is too much?
- Depends partly on the person
- Man within recommended BMI: 18% to 24% fat composition
- Woman within recommended BMI: 23% to 31% body fat
- Athletes: 5% to 10% for men, 15% to 20% for women
Health Risks of Obesity
- hypertension
- type 2 diabetes
- (high blood lipids, cardiovascular disease, sleep apnea, osteoarthritis, abdominal hernias, some cancers, varicose veins, gout, gallbladder disease, kidney stones, respiratory problems)
- Social stigma, prejudice
- Increased costs
- Insurance premiums
- Clothing
Causes of Obesity
- Genetics and weight
- Genes influence eating behaviour and weight
- Impact of body composition
- Complex interactions among genes
- Interrelated with environment factors
Genetics and Weight: Lipoprotein Lipase (LPL)
“lets store more fat!”
- cell surface enzyme that hydrolyzes triglycerides and promotes fat storage
- higher level of LPL activity in fat cells of obese people - makes fat storage efficient
Genetics and Weight: Leptin
- protein (hormone) coded for by obesity (ob) gene
- suppresses the appetite. After you eat a massive meal and have storage, leptin is produced and tells you you are full and do not need to eat anytime soon. It is a hormone that helps with natural regulation of feasting and fasting in normal routines
Genetics and Weight: Ghrelin
- hormone that stimulates appetite and promotes efficient energy storage
Fat Cell Development (4 steps)
- during growth fat cells increase in number
- when energy intake exceeds expenditure, fat cells increase in size
- when fat cells have enlarged and energy intake continues to exceed expenditure, fat cells increase in number again
- with fat loss, the size of the fat cells shrinks, but not the number
Obesity Treatment: Principles
- weight-loss advice does not apply equally to all overweight people
- many factors should be considered (extent of overweight, age, health, genetics)
- Must weigh the benefits and risks of weight loss
- Obesity treatment should integrate healthy eating patterns, physical activities, supportive environments, and psychosocial support
- Successful strategies embrace small changes, moderate and sustained losses, and reasonable goals
Reasonable Strategies for weight loss to lower disease risk
- reduce body weight by about 5% to 10% over 6 months
- A healthful eating plan
- Nutritional adequacy
- reduce body weight by about 5% to 10% over 6 months
Maintain a lower body weight over the long term
At minimum, prevent further weight gain
A healthful eating plan
A realistic energy intake
- provides less energy than the person needs to maintain present body weight
- Not too restrictive
- men: 1500-1800 kcalories per day
- Women 1200-1500 kcalories per day
Nutritional Adequacy
- difficult to achieve on <1200 kcal/day
- nutrient-dense food selections
- dietary supplement with <100% of daily values for minerals/vitamins
Reasonable Strategies for Weight Loss: A Healthful Eating Plan
- Small portions (less food at each meal, prepared meal plans can assist with portion control)
- Lower energy density (fruits, vegetables, broth-based soups)
- Sugar and alcohol (limit intake)
- Meal spacing (total quantity consumed should be controlled)
- Adequate water (substitute for nutrient-poor kcaloric beverages)
Reasonable Strategies for Weight Loss: Physical Activity
Physical activity: more likely to lose more fat, retain more muscle, and regain less weight when physical activity is combined with energy restriction. Reduces abdominal obesity; improves blood pressure, insulin resistance, fitness of heart and lungs
Energy expenditure: directly increases energy output. energy spent on various activities differs.
Basal Metabolic Rate (BMR): elevated following vigorous physical activity. Rises over time as more lean tissue is added
Those who maintain weight loss over time:
- Believe they have the ability to control their own weight, an attribute known as self-efficacy
- Eat breakfast everyday
- Average about one hour of physical activity per day
- Monitor body weight about once a week
- Maintain consistent lower calorie eating patters
- Quickly address small lapses to prevent small gains from turning into major ones
- Watch less than 10 hours of television per week
- eat high fibre foods, particularly whole grains, vegetables, and fruit, and consume adequate water each day. Cultivate and honour realistic expectations regarding body size and shape
Health Risk of being Underweight
- Inability to preserve lean tissue when fighting a wasting disease, e.g., cancer
- Menstrual irregularities and infertility
- Osteoporosis and bone fractures
- Anorexia nervosa
Strategies for Weight Gain
- Physical activity to build muscles (focus on resistance training with increased energy intake)
- Energy-dense foods (choose high-kcalorie items from each food group)
- Three meals daily
- Large portions (more food at each meal; extra snacks)
- Juice and milk (increase kcalories with beverages. High-protein, high kcal formulas for people who are underweight due to illness)
