Obesity Flashcards
What is the overweight BMI for Asian descent?
23-24.9
(pre-obese: 25-29.9)
What is the suggested daily calorie deficit to loose weight?
500-750kcal/day = 1Ib/week (3,500 calories = 1Ib)
How does a sedentary lifestyle drive obesity?
Less movement = reduced energy expenditure.
Insulin resistant muscles do not have stamina because they cannot get glucose in to generate ATP.
Motivate obese people to MOVE more, not necessarily exercise - they have poor stamina due to insulin resistance in muscles, glucose is stored as adipose, not glycogen.
What is AMPK?
Activated protein kinase - regulator of energy homeostasis, dependent on cell sensitivity to insulin.
AMPK = ATP production
IR = reduced AMPK = reduced catabolism of adipose + no message to liver to produce glucose for glycogen + continued production of triglycerides = weight gain and no energy
Exercise = increased AMPK (due to energy deficit) + GLUT 4 activation = glucose uptake = ATP
How does sleep drive obesity?
Reduced glucose tolerance and insulin sensitivity, increased ghrelin.
Increased consumption of food + unhealthy choices - seeking dopamine hit.
Increased inflammation (poor sleep = poor quality repair) intercepts leptin signalling to the brain (IL-6, TNF).
How would you improve sleep?
B6 = serotonin and melatonin
Chamomile, passion flower, magnesium
Reduce caffeine, blue light, anxiety, stress management, lighting, bedroom environment, epsom salts
How does Chronobiology drive obesity?
Shift work, sleep deprivation (hormonal imbalance), bright light exposure (circadian misalignment).
Shift work: obesity, dysregulation of triglycerides and cholesterol (higher peak post prandial glucose and reduced lipolysis as a result of late night eating), abdominal obesity, T2D, CVD.
Irregular eating = weight gain
Late night eating = circadian misalignment, dysbiosis
How does processed food drive obesity?
Bliss point + dopamine stimulators: (fat, salt, sugar, alcohol, caffeine, starch).
Dopamine reward > satiety signals
High fructose corn syrup (obesity, NAFLD, metabolic syndrome) - artificial sweeteners in drinks confuse hunger signals and increase sweet taste tolerance.
Trans fat - cell membrane rigidity - reduced cell communication - insulin resistance
How does stress drive obesity?
Alters eating behaviours - over eating, preference for comfort food (high GI, alcohol, dopamine promoting food).
Sleep deprivation
Cortisol > insulin, high, constant cortisol, glucose cannot reach cells = stored as triglycerides = central adiposity.
How does microbiome drive obesity?
Low Akkermansia = damage to mucosa - metabolic endotoxaemia - low grade inflammation and disrupted insulin signalling.
Traditional microbiome - carbohydrate-active enzymes to digest complex polysaccharides = SCFAs = microbiome health.
Low fibre = high mucus-utilising bacteria, dysiosis - low SCFAs - LPS - leaky gut - endotoxaemia - inflammation - blocks insulin
How does genetics drive obesity?
SNPs:
FTO = fat mass, not feeling reward from food ‘snacking’ gene
VDR = low vit D = inflammation in gut, dysbiosis
ADIPOQ = adiponectin deficiency (glucose regulation and FA oxidation)
SLC2A2 = consumption of sugar/predictor of T2D
