Chapter 9 HUN

 Overweight & Obesity

• Prevalence in the United States

  • Estimated 70 percent of adults

  • Increasing in children

• Worldwide problem

  • 1.9 billion adults and 41 million children <5yrs

• Global food system

  • Abundant energy-dense foods, ultra processed, affordable &effectively marketed products,

Fat Cell Development

• 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 energy expenditure, fat cells increase in number again.

• With fat loss, the size of the fat cells shrinks, but not the number.

• Fat cells are capable of increasing their size by 20-fold and their number by several thousand fold.

  Fat Cell Metabolism

• Enzyme Lipoprotein lipase (LPL)

  • Found mainly on surface cells lining muscles & adipose tissues

  • Energy or fat stores

Obese people more lpl activity in fat cells therefore more efficient fat storage

LPL activity in different regions of the body driven by sex

• Women adipose tissue in breast, hips and thigh

• Men in the abdomen (central obesity)

“Apple” and “Pear” Body Shapes Compared

 SET POINT THEORY

• Body maintains weight by means of its own controls

• The point at which controls are set

CAUSES OF OBESITY

• Genetics

  • Ob gene (obesity gene)

  • Codes for the protein Leptin

  • Secreted by adipose cells

  • Acts mainly on the Hypothalamus

  • Suppresses appetite

  • Increase energy expenditure

• Leptin (signals fullness to the brain) promotes negative energy balance

 CAUSES OF OBESITY

• Ghrelin (hormone like)

  • Secreted mainly in Stomach cells

  • Enhance appetite triggers desire to eat

  • Decrease energy expenditure

  • Increases with fasting, hunger & starvation

  • Decrease with food intake

 Uncoupling Proteins

• Genes code for proteins involved in energy metabolism

• Storing or expending of energy

• White fat VS Brown fat

• White  stores fat (higher in adults)

• Brown releases stored fat (higher in infants)

 CAUSES OF OBESITY

• Environment (obesogenic)

  • Overeating

  • High calorie foods

  • High fat foods

  • Fast foods

  • Oversized meals

  • Convenience foods (often ultra- processed)

 CAUSES OF OBESITY

• Physical Inactivity

  • Escalators

  • Automobiles

  • Computer age

  • Video games

  • Remote controls

 Problems of Overweight & Obesity

• Health Risks

  • Hypertension

  • Fatty lived Disease

  • Abnormal Blood Lipids

  • Diabetes/ prediabetes

  • Sleep apnea

 Problems of Overweight & Obesity

• Prejudice and discrimination

  • On the job

  • At school

  • Other social situations

  • Stereotyped

 PSYCHOLOGICAL  PROBLEMS

• Embarrassment

• Criticisms

• Rejection

• Depression

• Hurt self-esteem

  The Psychology of Weight Cycling

Yo-Yo Dieting

Cycle of weight –loss and gain

DANGEROUS INTERVENTIONS

• Fad diets: A fad diet is a diet that is popular for a short time and promises quick weight loss or health improvements without scientific evidence. Fad diets are often considered a type of pseudoscientific diet

• Over-the- counter drugs

• Herbal products and dietary supplements

• Other gimmicks

  • Hot baths

  • Steam and sauna

  • Body wraps

 AGGRESSIVE TREATMENT

• DRUGS

• Some FDA approved

  • SIBUTRAMINE

  • Suppresses appetite

  • Side effects

  • Increase heart rate

  • High BP

• ORLISTAT

•   Inhibits pancreatic lipase activity

• Blocking fat digestion

• Side effects

• Gas

• Frequent bowel movements

• Reduce absorption of fat-soluble vitamins

• Phentermine

  • Enhances the release of norepinephrine (suppresses appetite)

  • Increased blood pressure

  • Increased heart rate

  • Insomnia

  • Nervousness

  • Dizziness

  • headache

 SURGERY

• Reduce capacity of the stomach

• Suppress hunger

• Reduce production of ghrelin

 SURGERY

• CLINICALLY SEVERE OBESITY

• BMI 40 & above (approx. 9%of US adults)

• BMI >35 with obesity related problems

• Bariatric Surgery is most effective

  Gastric Surgery Used in the Treatment of Severe Obesity

• Gastric bypass: flow of food bypasses the stomach and portion of small intestine

• Gastric banding: The surgeon places a band around the upper part of your stomach to create a small pouch to hold food. The band limits the amount of food you can eat by making you feel full after eating small amounts of food.

• Sleeve gastrectomy: It removes a large portion of your stomach, leaving behind a narrow “sleeve.” Reducing your stomach helps restrict calories and reduce hunger signals. 

 Other Medical Procedures

• Endoscopic procedures

  • Intragastric balloon

  • Gastric aspiration

  • Liposuction

  Lifestyle Strategies

• What is reasonable rate of weight loss?

• ½ to 2 lbs per week

• 5 % to 10% body weight in a year

• Be realistic about energy intake

• Emphasize nutritional adequacy

• Eat small portions

• Eat slowly

• Lower energy density

  Energy Density

Selecting grapes with their high water content instead of raisins

increases the volume and cuts the energy intake in half.

Even at the same weight and similar serving sizes, the fiber-rich broccoli delivers twice the fiber of the potatoes for about one- fourth the energy.

By selecting the water-packed tuna (on the right), a person can enjoy the same amount for fewer kcalories.

Strategies

• Remember water

• Complex carbohydrates

• Choose fats sensibly

• Avoid empty calorie foods

• Set SMART goals

• Specific

• Measureable

• Attainable

• Relevant

• Time based

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• Physical Activity speeds up metabolism

• Physically active people have less body fat even with same BMI

• Control appetite

• Reduce stress

 BEHAVIOR MODIFICATION

• Become aware of behaviors

• Change behaviors

  • Small steps

  • Avoid major changes during stressful time

  • Personal attitude

  • Support groups