Obesity

Question 1

Definition of obesity; w/ BMI

Answer 1

• abnormal or excessive fat accumulation that impair health
• Obesity: BMI > 30
• Morbid Obesity: BMI > 40

Question 2

Thermogenesis Model for Obesity

Answer 2

• Body weight is very tightly regulated via a CNS set-point
• Set-point does not like weight loss, but it is relatively easy to gain weight: only requires 13 kcal/day excess (is a slippery slope)

Question 3

What is the dominant force affecting the obesity epidemic?

Answer 3

INTAKE
- It’s the # of CALORIES that count, not the content

• sedentary lifestyle and genetics are less important
• “The genetic background loads the gun, but the environment pulls the trigger”

Question 4

Drifty Gene Hypothesis

Answer 4

• explanation for why some people are slim
• Prehistoric: Thrifty genes: favors weight gain to store energy to prepare for times of fasting
• When stopped being pray, genetically evolved to allow body to become slim

Question 5

Lipogenesis/Metabolic model for obesity

Answer 5

• obesity explained by understanding how specific dietary products and activity behaviors perturb cellular metabolism and promote net lipogenesis

Question 6

Endocrine Secretions from White Adipose Tissue (WAT)

Answer 6

1. Adiponectin: Enhances insulin action, anti-inflammatory; decreased in obesity
2. Resistin: Causes insulin resistance, pro-inflammatory; increased in obesity
3. Visfatin: Increased in obesity
4. RBP4: Causes insulin resistance; increased in obesity

Question 7

Leptin

Answer 7

• Signals the brain (acutely at the arcuate nucleus) about the quantity of stored fat; tells body you are full
• suppresses Ghrelin
• Increased after eating and decreased with fasting
• secreted by subcutaneous fat cells
• can be overridden by cognitive influences

Question 8

Hallmark of adipocyte pathophysiology

Answer 8

INSULIN RESISTANCE

• can occur if too fat or too thin

Subnormal biological response to normal insulin concentrations
- increased Glucose, lipids, protein

Metabolic features: Metabolic syndrome

• Abd obesity
• Abn glucose
• High triglycerides/low HDL
• Hypertension

Question 9

Pear-Shaped Obesity

Answer 9

• increased subcutaneous fat

- low risk of diabetes and metabolic syndrome

Question 10

Apple-Shaped Obesity

Answer 10

• Increased visceral fat

- high risk of diabetes and metabolic syndrome