Weight Management PDF

Chapter 4: Weight Management 1  Body Composition Relative amount of fat mass (essential and storage) vs. the amount of fat-free mass (bone, muscle, organs, water-in-the body)...

Chapter 4: Weight Management 1  Body Composition Relative amount of fat mass (essential and storage) vs. the amount of fat-free mass (bone, muscle, organs, water-in-the body) 2  Body Fat Types Subcutaneous Fat: Located beneath the skin Critical for normal body functioning Visceral Fat: Located in the abdominal wall and around internal organs Excess leads to greater risk of heart disease, insulin resistance, and metabolic syndrome Ectopic Fat: Located on or within organs (liver, heart, and brain) 3  Increases the risk for metabolic syndrome, heart disease and stroke What Should I Weigh? Many factors determine what you weigh. There is no single best weight, but a range of healthy weights 4 5 What is the right weight for you?  Body Mass Index weight (kg) height (m2) Applies to M & F 18 years & over Underweight: BMI < 18.5 Risks include under nutrition, osteoporosis, & infertility Few health Normal: BMI 18.5-24.9 risks Overweight: BMI 25-29.9 Risks include Type II diabetes, hypertension, CVD, certain cancers 7 Obese: BMI 30 – 39.9 Very high risk Severely obese: BMI >40+ Very high risk Body Mass Index Limitations: Does not distinguish between fat weight and fat-free weight Muscular individuals may be incorrectly categorized as overweight or obese, as it does not reliably reflect body fat Not useful for (inaccurate measure): 8  Growing children or shorter people Pregnant women or nursing Elderly 9  Waist Circumference Used with BMI as a practical indicator of excess abdominal fat and associated risks Waist Circumference associated with increased risk for coronary heart disease, type II diabetes, hypertension in Caucasian men/women: Men: ≥ 102 cm/40 inches 10  Women: ≥ 88cm/35 inches Body Composition Assessment “Ideal” body fat percentage: men range from 7 - 25% women 16 - 35 % Methods of assessing Body Composition include: Skinfold fat measurement Hydrostatic weighing & Bod Pod Bioelectrical impedance analysis (BIA) 11  Dual energy x-ray absorptiometry (DXA) 12  Body Composition Assessment Skinfold Measurement: Using a skinfold calliper Measures subcutaneous fat at various sites (3-9) 13  Body Composition Limitations: Need flawless procedure Proper formula Proper sites measured Test-retest reliability 14  Body Composition Assessment Hydrostatic (Underwater) Weighing: Gold standard procedure Person is submerged in water Percent body fat is being calculated from the body density Limitations: Subjects must exhale completely and then submerge totally underwater up to 10 times 16  Body Composition Impossible to use with elderly, ill, or hospitalized patients Extremely expensive and not widely available 17  Assessment BodPod: Uses air displacement to measure body volume Computerized pressure determines the amount of air being displaced, providing info to calculate body composition density Fast, non-invasive, and easy procedure Well suited for special populations (children, elderly, obese, disabled) Limitations: Requires strict protocol to be followed 19  Body Composition Hydration status and increases in muscle temperature can influence results 20 21  Body Composition Assessment Bioelectrical Impedance Analysis (BIA): Low level electrical current is passed through body water and opposition to the flow of the current is measured Estimates the amount of skeletal muscle mass, total body water, and body fat Limitations: Hydration status can influence results 22 23  Body Composition Assessment Dual-energy X-ray absorptiometry (DEXA): X-rays are used to quantify the skeletal and soft-tissue components of body mass Radiation dose of patients performing DXA is considered negligible DXA assesses lean mass, fat mass and bone mineral Limitations: Hydration status can influence results Expensive and limited availability 24  Few trained technicians 25  Calculate your Lean Body Mass: Body Fat in LBs = Total Body wt x Body Fat % (in decimal form) Lean Body Mass = Total Body wt - Body fat in lbs. Ex. Someone who weighs 173 pounds with a body fat percentage of 17.5% would calculate as follows: (173)(.175) = 30.3 lbs. of body fat 173lbs - 30.3lb - 142.7 lbs of lean body mass Fat Increases mortality rate:  The Health Risks of Excess Body Reduces life expectancy by 20 years For the first time in history the current generation is at risk for shorter life expectancies than their parents One in 10 premature deaths are caused by obesity Associated with elevated cholesterol triglyceride levels, impaired heart function and death from cardiovascular disease Fat Other health risks: Diabetes Hypertension 29  The Health Risks of Excess Body Many cancers Impaired immune function Gallbladder and kidney disease Impotence Sleep and breathing disorders Back pain Skin problems Bone and joint disorders Fat Additional Issues: 30  The Health Risks of Excess Body Complications with pregnancy menstural irregularities Urine leakages (stress incontinence) Increased surgical risk Psychological problems/disorders: Depression Low self-esteem Body dissatisfaction Weight bias and stigma Bullying 31  The Health Risks of Excess Body Fat Health risks increase with severity Obesity is recognized as a chronic disease Small weight losses (~5-10% of total body weight) already leads to significant health improvements and increases quality of life Distribution of body fat is probably the MOST important indicator of health Men and postmenopausal women: apple shape Premenopausal women: pear shape 32  Android (Apple Shape) Characterized by excess abdominal faat fat Fat tends to be distributed viscerally More common in men Hard to lose Associated with: Smoking Alcohol (beer belly) Lack of exercise 33  Android (Apple Shape) Abdominal fat causes an increase in: Hypertension Risk of type 2 diabetes Stroke Early onset heart disease  Certain cancers Early mortality Gynoid (Pear Shape)  Characterized by excess hip/femoral fat fat Distributed primarily subcutaneously More common in women Associated with fewer health risks Easier to lose 28  Very Low Levels of Body Fat Problems Threat to wellness: Less than 12% body fat for women Less than 5% body fat for men Linked with: Reproductive, circulatory and immune system disorders Muscle wasting, fatigue, and likely linked with eating disorders Female Athlete Triad: Low energy availability (abnormal eating pattern and excessive exercise) 39  Amenorrhea (absence of menstruation) Decreased bone density (premature osteoporosis)  Factors Contributing to Excess Body Particularly present in sports where weight 41 and appearance are important: Ballet Gymnastics Skating Distance running Etc. If left untreated, the triad can lead to decreased physical performance, increased occurrence of fractures,  Factors Contributing to Excess Body disturbance of heart rhythm and metabolism, and even death Fat Genetic Factors More than 50 genes associated with obesity Genes influence body size, shape, fat distribution, metabolic rate Also affect the ease in which weight is gained due to overeating When both parents are obese, children’s at an 80% risk of becoming obese 43  However: not all children with obese parents end up obese (and vice versa) due to behavioral factors such as diet, exercise, sedentariness and sleep patterns Tendency to develop obesity may be inherited but the expression of the tendency is affected by environmental and behavioral influences Probabilities of Lean/Obese Parents Parents Ch ild Lean Obese  Factors Contributing to Excess Body Lean x Lean 90% 10% Lean x Obese 60% 40% Obese x Obese 20% 80% Fat Physiological Factors Metabolism: Sum of all vital processes by which food energy and nutrients are made available to the body 45  Key factor in the regulation of body fat and body weight Influenced by: Heredity Behavior Weight loss or gain Exercise  Factors Contributing to Excess Body Fat Physiological Factors Hormones: Hormones play a role in the accumulation of body fat, particularly in women during puberty, pregnancy, and menopause (estrogen, testosterone) Leptin: Secreted by the body’s fat cells, carried to the brain to give it info about the fat stores Key role in regulating appetite and metabolic rate (satiety and energy expenditure) Ghrelin: Secreted from the stomach & cells of the pancreas 47  Factors Contributing to Excess Body Stimulates appetite (increases before meal and decreases for ~ 3 hours after a meal) Fat Physiological Factors Fat Cells: Amount of fat stored is function of # and size of fat cells Some people are born with an above average number of fat cells and thus have the potential to store more energy as body fat Unclear whether fat cell number decreases once a person loses weight, but the fat cell content depletes Subcutaneous vs. visceral fat 48  Factors Contributing to Excess Body Little to no health risk with subcutaneous fat Visceral fat is dangerous as it increases the risk of developing chronic diseases Fat Lifestyle Factors: Eating: Calorie-dense foods containing high-fat and high sugar Relying on fast food or packaged convenience food Restaurant portion sizes and likely high in fat, sugar and low in essential nutrients 49  Factors Contributing to Excess Body Fat Lifestyle Factors: Physical Activity and Sedentariness: Physical activity has been declining in Canadians Schools have cut back on physical education and recess Most adults are inactive throughout the day ~15% were meeting the 24-hour movement guidelines before COVID-19, now this value decreased further Sedentariness is a risk factor for: Chronic diseases (i.e., obesity) 50  Factors Contributing to Excess Body Poor mental/physical health and poor cognitive functioning Decreased quality of life Fat Lifestyle Factors: Sleep: Short sleep duration and sleep deprivation are associated with increased BMI and obesity (link is still being researched) Possibly due to lack of sleep affecting hormone levels, appetite regulation, and metabolism Short sleep is connected with increased snacking and overall energy intake 51 What could be some public health responses to support positive lifestyle choices for weight management? 1. Change food pricing to promote healthy options 2. Limit advertising of unhealthy foods 3. Funding strategies to promote physical activity 4. Lower expense of memberships 52  5. Increase available exercise options 6. Limiting processed foods Factors Contributing to Excess Body Fat Psychosocial Factors: Food for Coping: Using food as a means of coping with and negative emotions Eating provides a powerful distraction from difficult feelings (i.e., loneliness, anger, boredom, shame, etc.) 53  When food and eating become the primary means of regulating emotions, binge eating, or other disturbed eating patterns can develop Factors Contributing to Excess Body Fat Psychosocial Factors: Food and Socioeconomic Status: Obesity is strongly associated with socioeconomic status Prevalence of obesity goes down as income level goes up More women than men have obesity at lower income levels 54  More men have obesity at greater income levels When food is an integral part of familial or cultural gatherings and celebrations, it can be difficult to change established eating patterns. 55 What Triggers Your Eating? Adopting a Healthy Lifestyle for Successful Weight Management Diet and Eating Habits: Total Calories: Energy balance is a more important consideration for weight management Energy in = energy out Lose weight – decrease caloric intake and increase physical activity Energy in < energy out 1 kg body fat = 7000 kcal Best approach is to increase physical activity with moderate caloric restriction (DO NOT go on a crash diet) Diet needs to incorporate all essential nutrients 59 Adopting a Healthy Lifestyle for Successful Weight Management Maintaining weight is harder than losing weight Diet and Eating Habits: Portion Sizes: Check serving sizes listed on packaged food To counteract portion distortion weigh and measure foods at home for a few days every now and then Energy (Calorie) Density: Number of calories per gram of food Add extra fruits and vegetables 60 Adopting a Healthy Lifestyle for Successful Weight Management Even products labelled as “fat free” or “reduced fat” may be high in calories due to containing sugar or fat substitutes Diet and Eating Habits: Eating Habits: 4-5 meals a day (including snacks) Skipping meals leads to excessive hunger, feelings of deprivation, and increased vulnerability to snacking and binge-eating Set rules to govern your food choices and treat yourself on special occasions Everything in moderation 61 Adopting a Healthy Lifestyle for Successful Weight Management No foods need to be completely off limits, but some should be eaten judiciously Physical Activity, Exercise and Sedentariness: Regular physical activities and exercise Reducing/breaking up long periods of sitting/sedentary time Sleep: 7-9 hours of sleep Limit caffeine and alcohol close to bedtime (decreases sleep quality) Avoid electronic screens within 1 hour of bedtime 62 Adopting a Healthy Lifestyle for Successful Weight Management Establish consistent bed and rise times Create a wind-down routine Thinking and Emotions: Positive and motivating self-talk Having realistic goals and beliefs Practice problem-solving skills Coping Strategies: Find coping strategies other than food, drugs or alcohol i.e., developing a support system, exercise, setting realistic goals 63  Why Diets Typically Don’t Work Obesity is a chronic diseases, which requires long-term lifestyle changes Strategies need to be realistic and sustainable or the weight is typically gained back Dieters are misdirected More concerned about weight loss than healthy, sustainable lifestyle Diets don’t typically address the root cause Most diet promote fast weight loss, but weight loss takes time 64  Steady weight loss averages 0.25-1.0 kg per week 65  Eating Disorders A serious disturbance in eating patterns or eating related behavior Characterized by a negative body image and concerns about body weight/fat 1 in 7 males and 1 in 5 females suffer from an eating disorder Steered by distorted thinking, perfectionistic beliefs, unreasonable demands for self-control and excessive self-criticism Environment is one factor in developing eating disorders: Abuse or hostile family Comparing oneself to others 67  Eating Coping mechanism (which may reduce anxiety by producing numbness and alleviating emotional pain) Disorders Anorexia Nervosa: Does not eat enough food to maintain a healthy body weight Have an intense fear of gaining weight or becoming fat Self-starvation Due to extreme weight loss stop menstruating, become cold intolerant, dry skin (covered in fine hair) and develop low BP and HR Affects 1% of North Americans (90% of those are female) 68  Eating Typically develops during puberty and late teenage years 1 in 10 people die of heart failure (due to electrolyte imbalance) Disorders Bulimia Nervosa: Characterized by binge-eating followed by purging Some binge and purge occasionally, others do it multiple times a day Appear to eat normally (thus, hard to recognize) and maintain normal weight Binging usually occurs privately or secretly During binge, all feelings are blocked out During purge, feel ashamed and terrified to gain weight from binging 69  Eating Binge and purge as a way of coping with their feelings 90% of bulimia nervosa cases are females Develop tooth decay, liver and kidney damage, cause cardiac arrhythmia Disorders Binge-Eating Disorder: Characterized by uncontrollable eating, usually followed by feelings of guilt and shame with weight gain Leads to rigid dieting, which leads to feelings of deprivation and a return to overeating (binge) Overeat compulsively not because of hunger 70  Eating Using food to cope with stress, conflict, or other difficult emotions People who binge-eat almost always are obese Higher rates of depression and anxiety 71  Summary Many factors contribute towards successful weight management; individual and societal (i.e., lifestyle behavior, family history, the environment) The key to weight management is maintaining a balance of calories in (food) and calories out (resting metabolism, food digestion and physical activities). There are a number of techniques available for body composition measurements. It is important to assess the pros and cons of each to enable the best choice for the individual. 73  Too much and too little body fat is linked with health problems; the distribution of body fat can also be a significant risk factor. Summar y An inaccurate or negative body image is common and can lead to psychological distress and disordered eating. Genetic factors help determine a person’s weight, but the influence of heredity can be overcome with attention to lifestyle factors. 74  Physiological factors involved in the regulation of body weight and body fat include metabolic rate, hormonal influences, and the size and number of fat cells. Nutritional guidelines for weight management include consuming a moderate number of calories; limiting portion sizes, energy density and intake of fat, simple sugars, refined carbs, and protein intakes; and developing an eating schedule and rules for food choices. 75  Summar y Weight management requires developing positive, realistic self-talk and self-esteem and a repertoire of appropriate techniques for handling stress and other emotional and physical challenges. Dissatisfaction with weight and shape are common to all eating disorders. Anorexia Nervosa is characterized by self-starvation, distorted body image, and intense fear of gaining weight. 76  Bulimia Nervosa is characterized by recurrent episodes of uncontrolled binge eating and frequent purging. Binge eating disorder involves bine eating without regular use of compensatory purging. 77