Transcript Document

WEIGHT
MANAGEMENT
Chapter 14
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 COMPOSITION
 Visceral

Fat
Fat surrounding organs (within abdomen)
 Subcutaneous

Fat just below the skin
 Percent

Fat
Body Fat
Definition: Proportion of the body’s total weight that is
fat
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© 2008 McGraw-Hill Higher Education. All rights reserved.
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 = underweight

18.6 - 24.9 = healthy

25-30 =overweight

Over 30 = obese
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METHODS
FAT
•
OF
DETERMINING PERCENT BODY
Hydrostatic (underwater) weighing
Most accurate
– Lean tissue is more dense than water; Fat tissue is less dense
than water.
– Therefore a person with more body fat will weigh less
underwater and be more buoyant
–
•
Skinfold measurements
–
•
Electrical Impedance Analysis
–
•
Measures thickness of fat under the skin
Electricity prefers lean tissue
Scanning procedures
–
CT scan, MRI, Dual-energy X-ray produce images to view
amount & location of fat
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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
– When energy in > energy out
(Gain weight over time)
– When energy in < energy out
(Lose weight over time)
–
Maintain weight
positive energy balance
negative energy balance
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BODY FAT DISTRIBUTION AND
HEALTH
 Apples



Men and postmenopausal women
Store fat in abdominal area
Increased risk of high blood pressure, diabetes,
early-onset heart disease, stroke, cancer
 Pears


Premenopausal women
Store fat in hips, buttocks, thighs
 Assessed
by measuring waist
circumference

> 40 inches for men and 35 inches for women is
considered a risk
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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 Triad
1. Abnormal eating patterns
2. Amenorrhea
3. Decreased bone density
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FACTORS CONTRIBUTING TO EXCESS BODY
FAT
 Genetic Factors
Genes influence body size, shape fat distribution
 300 genes have been linked to obesity

 Physiological

Factors
Metabolism
Low BMR = Basal 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
Image
 Severe
body
image
problems
Body
dysmorphic
disorder (BDD)

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EATING DISORDERS
•
Anorexia Nervosa - Failure to eat enough food to
maintain a reasonable body weight
–
Characteristics
•
–
Health Risks of Anorexia Nervosa
•
•
•
•
–
Fear gaining weight, distorted self-image, compulsive behaviors and
rituals, excessive exercise
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 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
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EATING DISORDERS
•
Binge-Eating - Similar to Bulimia except no
Purging behavior.
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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