Aspects of Obesity Flashcards
What is obesity due to?
Energy imbalance = people take in too much energy and/or do too little exercise
What is the thrifty genotype?
Genotype evolved by humans that optimised response to feeding opportunities = maladaptive in an environment where access to food is constant
What is the variant of the FTO gene implicated in?
BMI and also predisposes to childhood obesity = affects food intake by making people eat more
What are the health consequences of obesity?
Hypertension, cancer, gallbladder disease, renal failure, stroke, heart failure, atherosclerosis, type 2 diabetes
What may the link between obesity and cancer be due to?
May be mediated by high levels of insulin and/or oestrogen in obesity
What are the co-morbidities of obesity?
Osteoarthritis, back pain, asthma, sleep apnoea
What does adipose tissue secrete?
Adipocytes secrete adipokines = leptin, CRP, TNF alpha, adiponectin, IL-6, cortisol, oestrogen
What does leptin do?
Tells body how thin you are = if you don’t have leptin/leptin receptors then the body thinks you’re starving and acts accordingly
How is obesity linked to atherosclerosis?
Adipocytes and macrophages share functions = in obesity adipocytes secrete cytokines and macrophages accumulate fat, becoming foam cells which are found in atherosclerotic plaques
What are some dietary interventions for obesity?
Hypocaloric diets = take in less calories than being used
Options = portion control/calorie counting, low carb/fat, very low calorie diet, meal replacement
What is a drug commonly used to treat obesity?
Orlistat
How does orlistat work?
Block absorption of dietary fat by inhibiting lipase, up to 1/3 of ingested fat excreted into faeces
What are the types of bariatric surgery?
Restrictive or malabsorptive = banding and sleeves are restrictive, bypass is both restrictive and malabsorptive
What are the most common bariatric surgeries done in the UK?
Adjustable gastric band = simplest, prone to slipping
Roux-en-Y gastric bypass
Vertical sleeve gastrectomy
How is the resting metabolic rate (RMR) calculated?
Amount of energy expended at rest - minimum energy consumption
