Exam #1: Obesity I Flashcards
What is the definition of obesity in adults? Children?
Adults= >30 Children= >95th percentile on growth chart
*Morbid= >40
How is BMI calculated?
weight/height
What are the limitations of the BMI?
- Measure of excess body weight, not necessarily fat
- Does not take lean mass into account
- Does not distinguish distribution of fat
What are the waist circumferences that place one in a high risk category?
Male= >40 inches Female= > 32 inches
What are the definitions of obesity I, II, and III?
I= 30-34.9 II= 35- 39.9 III= >40
List diseases that obesity is a risk factor for.
CVD DM CVA HTN DM Cancer Gyn abnormalities OA Gallstones
What is the definition of Metabolic Syndrome?
3/5 of the following:
- Elevated waist circumference
- Elevated TG
- Reduced HDL
- HTN
- Elevated fasting glucose
What are some of the major factors affecting obesity?
- Decreased physical activity
- Bigger portions
- Refined carbohydrate consumption
- Media/ marketing
- Fast food consumption
- Packaged food consumption
What are the organic diseases that can lead to obesity?
- Polycystic Ovarian Syndrome (PCOS)
- Hypothyroidism
- Cushing’s Syndrome
What types of medications can induce weight gain?
- Glucocorticoids/ steroids
- Antypsychotics/ mood stabilizers
- Antidepressants
- DM
- Antiepileptic
From an evolutionary perspective, what are the three major arguments for the obesity epidemic we have today?
1) Adaptive
2) Maladaptive
3) Neutral
What is the adaptive evolutionary argument for obesity?
- Fat accumulation advantageous
- Famine selected for genes (thrifty genes) that favored deposition
*****This has become disadvantageous in modern society
What is the maladaptive evolutionary argument for obesity?
- Obesity has never been advantageous
- Obesity coupled with advantageous factor– Brown Adipose Tissue (BAT)
What is the neutral evolutionary argument for obesity?
Set Point
- Lower intervention limit set by starvation
- Upper set by risk of predation
*****The development of social behavior, weapons, and fire has diminished pressure on upper limit
What regulates energy homeostasis?
- Brain
- GI Tract
- Adipose tissue
What hormones/ messengers are involved in appetite?
- Leptin
- Ghrelin
- GLP-1
- Adiponectin
What is the prandial state?
- Eaten and newly ingested/ absorbed nutrients are available
- Generate “satiety” signals and inhibit “hunger” signals
- Nutrients are rapidly used or stored
What is the post-absoprtive state?
- No calories entering circulation from GI tract
- No satiety signals
- Hunger signals generated
- Stored energy released into blood
What are the satiety hormones?
CCK
PYY
GLP-1
Leptin
What is the hunger hormone?
Ghrelin
What is the function of CCK?
- Small intestine releases in response to feeding
- Causes release of digestive enzymes from pancreas & bile from gallbladder
What is the function of PYY?
Insulin peptide hormone released by pancreas in response to high blood sugar
What are the function of GLP-1?
- Increased insulin secretion and sensitivity
- Decreased glucagon secretion
- Inhibition of acid secretion
- Inhibits gastric emptying
What is the function of Leptin?
- Released by adipose tissue
- Binds leptin receptors in hypothalamus to signal satiety
*****Note that mice knockouts are obese; humans can get “leptin resistance” from chronic overeating
What is the function of ghrelin?
- Produced by stomach and pancreas
- Secreted when stomach is empty
- Increases gastric acid secretion & GI mobility
What is the difference between physical and emotional hunger?
See ppt.
