Eat Less Burn More Flashcards
How can we prevent/treat obesity and diabetes?
Lifestyle changes
Psychological therapies
Bariatric surgery
Therapeutic agents to reduce body weight
Name some lifestyle changes to treat obesity and diabetes
Do these work?
Dieting and exercise
Generally do not produce a marked sustainable weight loss in the general population
What is a psychological therapy that can be used to treat obesity?
What is the issue with this?
CBT
Not able to deliver it on a mass scale
Advantages and disadvantages for using bariatric surgery to treat obesity
Advantages - very effective
Disadvantages - expensive, reserved for morbidly obese individuals, risks of the procedure, have to have some weight loss before surgery
How may therapeutic agents help treat obesity?
They increase energy expenditure and/or decrease consumption/absorption of food
Noradrenergics:
What do they do to help obesity?
Side effects
Are they approved?
They are appetite suppressants that inhibit noradrenaline uptake
CVD side effects
Not approved for use
Seratonergics:
What do they do to help obesity?
Side effects
Are they approved?
Appetite suppressants that act on 5-HT system
Some induce heart disease, some caused a return to original weight after weight loss
Not prescribed
What is the current drug for treatment of obesity?
Orlistat
How does orlistat work?
By inhibiting pancreatic lipase thus decreasing triglyceride absorption, reducing fat absorption in the small intestine
Side effects of orlistat
Cramping
Diarrhoea
Bloating
Flatulence
Abdominal pain
Why do you need to take vitamin supplements if you are prescribed orlistat?
Because you lose fat soluble vitamins e.g. vitamin A, vitamin D and vitamin E
Is orlistat effective?
Not particularly - only lose about 3kg in 12 months
Tendency to get rebound weight
Liraglutide:
Drug class
Dosage
Concerns
GLP-1 agonist (GLP-1 is a satiety peptide)
3mg produces 5-10% weight loss
Concerns about thyroid and pancreatic cancer
Semaglutide:
Drug class
Dosage
Is it easy to get?
Is it more or less effective than liraglutide?
GLP-1 agonist
2.4mg weekly sc injection
No - there are strict rules on the NHS
More effective than liraglutide - produces 15-20% weight loss and less side effects
How does weight loss surgery work?
It limits the amount of food that the stomach can hold, making the individual feel full after a small meal
Types of bariatric surgery
Adjustable gastric band
Route-en Y gastric bypass
Vertical sleeve gastrectomy
What happens in adjustable gastric band surgery?
A band is placed at the top of the stomach to limit food entry to the stomach
What happens in route-en Y gastric bypass?
The digestive tract is rerouted, by-passing most of the stomach and small intestine, accelerating the GI transit of food
What happens in vertical sleeve gastrectomy?
Part of the stomach is removed leaving a sleeve, so reducing the size of the stomach, lowering food intake and increasing gastric emptying
What is the most common type of bariatric surgery?
Vertical sleeve gastrectomy
What percentage weight loss does gastric produce?
50-60% in one year that is sustainable
How quickly does a dramatic improvement in glucose homeostasis and insulin sensitivity occur following bariatric surgery?
Within 1 week, before significant weight loss occurs
What is energy expenditure?
Heat produced + work done
What is obligatory energy expenditure?
Basic cell and organ physiological needs
What is adaptive energy expenditure
Physical activity and adaptive thermogenesis
Brown adipose tissue contains lots of/few mitochondria
Lots of mitochondria
How is proton leak in brown adipose tissue regulated?
By UCP1
How is heat generated in brown adipose tissue?
Proton movement
How is UCP1 activated?
By long-chain fatty acids
What is the function of brown adipose tissue?
To generate body heat in animals or newborns that do not shiver
What are UCPs activated by?
Fatty acids and free radicals
What is UCP expression induced by?
Metabolic and oxidative challenge:
Cold temperatures
Dietary restriction
Exercise
