4.6 Causes, Diagnosis and Treatment of Weight Disorders Flashcards
Why are early-life obesity intervention programs so important?
- Children who are overweight/obese as preschoolers are FIVE TIMES as likely to be obese adults
- The earlier we stop the obesity, the less it seems to persist through life
Describe the benefits/limitations of BMI
Benefits: great for rough idea of weight and risk
Limitations: does not take into account body composition (bodybuilders, women have more fat, older people have more fat)
Describe the benefits/limitations of tricep skinfold test
Benefits: cheap, fast, non-invasive
Drawbacks: does not account for visceral fat, variations of fat distribution (disease, genetics etc.)
Describe the benefits/limitations of waist circumference test
Benefits: better indicator of disease risk than BMI, can be adjusted for gender/race
Limitations: does not differentiate between visceral/subcutaneous fat
True or false: subcutaneous fat stores are notable for their ability to cause low-grade inflammation
- Not really
- This applies much more to visceral fat; another reason why obesity can cause insulin resistance
True or false: exercise is the best known way to lose weight
- False
- It mostly comes down to diet (remember Alex Hormozi)
List three physical activity goals to improve metabolic health
Goal 1: Reduce sedentary time
Goal 2: 30mins walking/day
Goal 3: 150mins moderate to vigorous activity per week
Why is it a good idea to add fat and protein to carbohydrates?
- Slows gastric emptying
- Reduces insulin spikes
How can we improve the healthfulness of our carbohydrate intake?
- Swap simple carbohydrates (e.g. white bread) for more complex carbohydartes (wholemeal bread)
- Slows glucose spike
What are the healthier/less healthy types of fat to eat?
- Saturated/trans are less healthy
- Unsaturated are healthier
Why are ultra-processed foods harmful? What is their effect on chronic disease risk?
- High in fat, salts, and sugar. Designed to override satiating mechanisms
- Causal in chronic disease
What are the effects of leptin deficiency? How do we treat it?
- Loss of hunger reduction; severe obesity at young age
- Treated with metreleptin (synthetic leptin analogue)
If the adipostatic mechanisms keep bodyweight within a range, why does ultraprocessed foot make everybody fat?
- High levels of fats, sugars, and salts override satiety mechanisms
- This alters the body’s bodyweight setpoint, leading to obesity
What are two kinds of diets that have shown to be effective for weight loss?
- Time restriction
- Caloric restriction
True or false: lifestyle interventions are 30% more effective than metformin for people with prediabetes
True. Get fucked, metformin companies.
We have an obese patient. We’ve tried reduced energy diet, and pharmacotherapy, but we need more. What’s the next step?
Bariatric surgery.
How does the body “defend” against weight loss?
- As you lose weight, your energy expenditure decreases
- In turn, this makes it harder to enter energy deficit, and lose more
(leptin also decreases, meaning more hunger)
What are the long-term effects of weight loss on appetite? Why does this make sense if you’re a caveman?
- Appetite increases, and is sustained even after calorie deficit is gone
- If your environment is unstable, you need to get while the getting’s good
Give two examples of drugs that can be used for pharmacological assistance of weight loss, and explain their mechs
- Orlistat (inhibits lipase enzymes)
- Semaglutide (GLP-1 agonist)
True or false: bariatric surgery comprises a complete obesity management plan
- FALSE
- Must be done alongside lifestyle modifications
For which patients do we consider bariatric surgery?
- All conservative measures have failed
- Severe weight-related complications
How does gastric surgery address loss of satiety in obese patients?
- Limits portion size they can ingest (like in gastric sleeve)
- Interferes w/ calorie absorption
- Affects gut-brain satiety (stretch receptors triggered earlier)
Who are patients assessed by before they meet a surgeon for possible bariatric surgery?
- Dietician
- Psychologist
- Endocrinologist
List selection criteria for bariatric surgery
- BMI >40 (or >35 w/ severe medical issues)
- Past concerted weight loss attempts
- Age 16-65
- No alcohol/drug dependency
- Willing to commit to long term modification
Up until ~10 years ago, what was the most common bariatric surgery? How did it work?
- Laparoscopic banding
- Collar placed around fundus of stomach
- Attached to subcutaneous port
- Fill port w/ saline to adjust collar size (and therefore restriction of food intake/satiety)
What are some complications of laparoscopic band stomach surgery?
- Dissolving band
- Slipping band
- Tubing issues
What is the most common bariatric surgery? How does it work anatomically?
- Gastric sleeving
- Greater curvature of the stomach is removed, only 15% of normal volume remains
Gastric sleeving/bypass complications
- Sleeve re-expansion (for sleeving)
- Leakage
- Stenosis
- Reflux
What is the most effective form of bariatric surgery? How does it work?
- Gastric bypass
- Small pouch in distal oesophagus
- Connects directly to jejunum
