Obesity Flashcards
What is the definition of obesity?
A condition of abnormal or excessive fat in accumulation in adipose tissue to the extent that health is impaired
How is obesity defined clinically?
Use BMI:
Healthy weight = 18.5-24.9 Overweight = 25-29.9 Obesity I = 30-34.9 Obesity II = 35-39.9 Obesity III = >40
Why is the BMI not an accurate indicator of obesity?
BMI is affected by muscle mass - increased muscle mass can drive a high BMI (not to do with excessive fat)
How important are genes Vs environment to developing obesity?
Genes = 60-80% Environment = he doesn't mention
How do genes increase / decrease chances of developing obesity?
Genes affecting: Fat storage Weight at birth Hormone release etc.
Why are more people getting obese now than before (e.g. 80s)?
Environmental factors - too short period for genetic change, so must be environmental
What is an obesogenic environment?
Env. that makes you more likely to be obese e.g.
Food market - cheap, tasty food = high sugar / fat / salt content = very high calories (food is cheapest it has ever been in correspondence to minimum wage)
How do the following factors increase or decrease obesity rates?
Parks / playground proximity Screen time Car use Higher education achievement Poverty
Further away closest park / playground = higher obesity rate
Increased screen time = higher obesity rate
Increased use of cars > public transport / walking = higher obesity rates
Higher education achievement = lower obesity rates
Earning less = higher obesity rates
What are some other factors associated with obesity?
Ethnicity Mental health Alcoholism Smoking Occupation Food availability / neighbourhood Food intake Social media
How does nature (genes) interact with nuture (environment) to the development of obesity?
Genes = predisposition Env. = trigger
So even if you have genes that give you a predisposition to obesity, a non-obesogenic env = less likely to develop obesity
Predisposition + trigger = more likely to be obese
What co-morbidities is obesity associated with?
Depression - social media, judgmental society Stroke MI CVD Sleep apnoea Type II diabetes Hypertension Osteoarthritis (knee and hip replacements) Gout Bowel cancer Peripheral vascular disease
Why is there a link between obesity and mortality?
Due to the co-morbidities
How can obesity be treated?
- Determine degree of obesity - use BMI, look at muscle mass
- Examine lifestyle, co-morbidities, willingness to change lifestyle
- Lifestyle changes, drug treatment
- Refer to obesity clinics / specialist care
- Specialist assessment and management = more invasive interventions - e.g. surgery, etc.
What are some drugs that can help treat obesity?
e.g. orlistat - contains endogenous lipstatin
Inhibits gastric and pancreatic enzymes
Reduces dietary fat absorption in the gut from ingested food about 30%
What are some side effects of orlistat?
Not life-threatening, but uncomfortable Steatorrhoea - oily / fatty stools Possible deficiencies of fat-soluble vitamins Oily spotting Faecal urgency
Why is it so difficult to make effective drugs for obesity?
Genetic factor
Interfering with metabolism can be dangerous (e.g. DNP)
Side effects
Many contributing factors to obesity - other pathways may compensate
What is the criteria for bariatric surgery?
BMI of >40
BMI 35-40 and other co-morbidities
BMI of 30-34.9 for newly diagnosed T2DM
Also: non-surgical measures have failed for at least 6 months, is receiving / will receive intensive specialist management, fit for anaesthesia and surgery and will commit to long-term follow-up
Surgery considered first line for BMI of >50
What are the 3 most common types of bariatric surgery?
Gastric bypass - top of stomach attached to small intestine so you feel full faster
Gastric Band - band placed around stomach to also make you feel full faster
Sleeve gastrectomy - part of the stomach is removed, almost becomes almost part of the duodenum so you feel full faster
All help reduce food intake by making you feel full faster
How effective is bariatric surgery?
V. effective, initial 30% drop in weight, then increases a little but stays level
What can society do to help combat obesity?
Higher sugar tax
Better food labeling laws e.g. low fat is often just high in sugar
Education
