WEIGHT MANAGEMENTChapter 14

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HEALTH RISKS ASSOCIATED WITH EXCESS BODY FAT Obesity Is associated with:

Unhealthy cholesterol and TG levels Impaired heart function CVD Hypertension Cancer Impaired immune function Gallbladder and kidney disease Skin problems Impotence, sleep disorder back pain, arthritis Type II diabetes (strong association)

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BODY FAT Visceral Fat

Subcutaneous Fat

Percent Body FatDefinition:

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EVALUATING BODY WEIGHT AND BODY COMPOSITION

Methods for Evaluating Obesity Body Mass Index (BMI): Calculated by the following equation: Weight in pounds

X 703 / Height in inches (squared) Under 18.5 =

18.6 - 24.9 =

25-30 =

Over 30 =

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METHODS OF DETERMINING PERCENT BODY FAT

• Hydrostatic (underwater) weighing

• Skinfold measurements

• Electrical Impedance Analysis

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ENERGY BALANCE

Energy balance equation: Energy in = caloric intake from food Energy out = caloric expenditure

Resting metabolism Digestion Physical activity

When energy in = energy out Maintain weight Calories > Energy out positive energy balance (Gain weight

over time) Calories < Energy out negative energy balance (Lose weight

over time)

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BODY FAT DISTRIBUTION AND HEALTHApples

Pears

Assessed by measuring waist circumference

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PROBLEMS ASSOCIATED WITH VERY LOW LEVELS OF BODY FAT

• Low % body fat has been linked to problems with the Reproductive, Circulatory, & Immune systems

• Female Athlete Triad1. Abnormal eating patterns2. Amenorrhea3. Decreased bone density

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FACTORS CONTRIBUTING TO EXCESS BODY FAT

Genetic FactorsGenes influence body size, shape fat distribution300 genes have been linked to obesity

Physiological FactorsMetabolism

Low BMR/RMR = Basal/Resting Metabolic Rate (number of calories you'd burn if you stayed in bed all day)

Hypothyroidism=

Hormones Leptin

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FACTORS CONTRIBUTING TO EXCESS BODY FAT

Lifestyle Factors Eating

Easy access to high calorie foods Eating out of proportion

Physical Activity Reduced

Psychosocial factors Emotions Coping strategies

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PSYCHOLOGICAL PROBLEMS ASSOCIATED WITH WEIGHT

Body ImageSevere body

image problems like Body dysmorphic disorder (BDD) can exist

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EATING DISORDERS• Anorexia NervosaAnorexia Nervosa - Failure to eat enough food

to maintain a reasonable body weight

– Characteristics• Fear gaining weight, distorted self-image, compulsive behaviors

and rituals, excessive exercise

– Health Risks of Anorexia Nervosa• amenorrhea• Intolerant of cold• Low blood pressure and heart rate• Depression and suicide

– Medical complications• Disorders of the cardiovascular, gastrointestinal, endocrine, and

skeletal systems

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EATING DISORDERS• Bulimia NervosaBulimia Nervosa - recurring episodes of binge

eating followed by purging

• Characteristics:• Rapid food consumption, followed by purging; afterwards feels ashamed, disgusted, physically and emotionally drained.

• Health Risks:– Erodes tooth enamel– Cardiac arrhythmia– Esophageal tearing– Rupture of the stomach– Menstrual problems– Increased depression 14

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EATING DISORDERS

• Binge-EatingBinge-Eating - Similar to Bulimia except no Purging behavior.

• Characteristics– Eating patterns - very rapid, eating until

uncomfortably full.– Often eat as a way of coping.– Likely to be obese.– High rates of depression and anxiety

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