8a. Obesity Flashcards
What is the definition of obesity?
Abnormal or excessive fat accumulation that presents a risk to health
What’s the BMI range for a healthy weight?
18.5-24.9
What’s the BMI range for overweight?
25-29.9
What’s the BMI range for obesity?
30-39.9
What, in society, has led to the rise in obesity?
Larger portion sizes
Abundance of food
Rise of convenience food
Food palatability/density
Snacking
Speed of eating
How many kcals daily are needed in deficient for an adult to lose weight?
500-750/day
Examples of conditions obesity increases the risk of
Diabetes
Arthritis
Endometriosis
Cancer
CV disease
What are the common drivers of obesity?
Sedentary lifestyle
Sleep disruption
Processed foods
Microbiome
Long-term cortisol
Genetics
Chronobiology
Why is a sedentary lifestyle a driver of obesity?
Leads to reduced energy expenditure
Why does exercise help with obesity?
Increased energy expenditure
Increased cellular AMPK
Increased GLUT4 activation/glucose uptake
Enhanced ATP production
Why is sleep disruption a driver of obesity?
Creates a hormonal imbalance that promotes overeating and weight gain
What are the hormonal imbalances associated with sleep disruption?
Reduced glucose tolerance and insulin sensitivity
Increased ghrelin levels - promoting hunger and unhealthy food choices
Activation of inflammatory pathways
Why is chronobiology a driver of obesity?
Shift work, sleep deprivation and exposure to bright light at night increase the prevalence of adiposity
What conditions/signs are more likely to increase for shift workers?
Triglycerides and cholesterol dysregulation
Abdominal obesity
T2D
CV disease
Why are shift workers more at risk of becoming obese?
Exposure to bright light
Sleep deprivation
Irregular eating patterns
Late night eating
Why can late night eating cause obesity?
Higher peak post-prandial glucose levels
Reduced lipolysis
Dysbiosis
Circadian rhythm misalignment
What should shift workers try to do to avoid obesity?
Regular eating pattern
Avoid stimulants - sugar, caffeine
Nourishing snacks
Why can processed foods be a driver for obesity?
Fats, salt, sugar, caffeine, starches all stimulate dopamine
Activate reward system to trigger cravings for more
Reward system and food palatability override satiety signals
Which artificial sweetener has a strong association with obesity, NAFLD and metabolic syndrome?
High fructose corn syrup
Why are high cortisol levels a driver for obesity?
Cortisol levels are elevated in obese individuals
Associated with enhanced abdominal fat deposition
Altered eating habits - more food, and energy dense food
Why is the microbiome a driver for obesity?
Low plant fibre content of Western diet = reduced SCFAs and increased mucus utilising bacteria
Lack of Akkermansia linked with obesity
Why is a lack of Akkermansia linked with obesity?
Low Akkermansia can contribute to damaged mucosal barrier
Leads to metabolic endotoxaemia
Leads to disrupted insulin signalling/low grade inflammation
SNPs on which genes are associated with obesity?
FTO
VDR - ongoing inflammation/gut permeability
SLC2A2 - habitual consumption of sugar
ADIPOQ - adiponectin deficiency
What is adipose tissue?
Metabolically active organ which regulates whole-body energy homeostasis
What are the three types of adipose tissue?
White adipose tissue
Brown adipose tissue
Beige-white adipose tissue
What is white adipose tissue used for and where is it stored?
Use: long term energy usage
Found: subcutaneous adipose tissue - under skin (wobbly bits)
Visceral adipose tissue - around organs
When is brown adipose tissue more abundant?
Early life
Which adipose tissue is associated with obesity and why?
White adipose tissue
Persistent energy surplus = increase in size and number of adipocytes = WAT expansion = obesity
(like a balloon)
What conditions is hypertrophy (increased size of adipocytes) associated with?
IR
T2D
NAFLD
Dyslipidaemia
What physiological factors create satiety?
Mechanical stretch of the stomach via Vague nerve
Hormones and peptides - CCK, GLP-1
Neuropeptides and neurotransmitters - serotonin, neuropeptide Y
Thyroid hormones, oxytocin, cortisol, insulin, glucagon
Which cells produce satiety hormone leptin?
Adipocytes
How does leptin work?
Released from adipose tissue to CNS
Regulates food intake and energy expenditure
Released in diurnal pattern (during day)
What is leptin resistance?
Reduced sensitivity or failure in response of the brain to leptin
What are leptin levels like in obesity?
High
But don’t work efficiency due to leptin resistance
(High adipose tissue = increased leptin resistance)
What does leptin resistance lead to overtime?
Metabolism
Abdominal weight gain
Chronic fatigue
Sleep dysregulation
When are ghrelin levels usually high?
Before a meal
When are ghrelin levels usually at their lowest?
Within 1 hour of eating
What are ghrelin levels generally like in obesity?
Low
What does losing weight do to ghrelin levels?
Increases them
What is the role of adiponectin?
Increases glucose uptake
Beta-oxidation of fats
Increases insulin sensitivity
Anti-inflammatory
Which conditions are reduced adiponectin associated with?
Insulin resistance
T2D
Obesity
CVD
What are significant predictors of plasma adiponectin levels?
BMI
Visceral fat
What is a low adiponectin:leptin ratio likely to increase?
Oxidative stress
Inflammation
Natural solutions to increasing adiponectin levels
Blueberries
Turmeric
Green tea
Cold water therapy
Daily HIIT
What drives insulin resistance?
Inflammation
What does inflammation drive?
Insulin resistance
Causes and risk factors for insulin resistance
High oxidative stress - poor sleep, toxins
Reduced physical activity - reduces GLUT4 expression
Chronic stress - increases glucose, lipids, cytokines
Mitochondria dysfunction - increased ROS, low ATP
Poor methylation - high homocysteine, hypertension
Dysbiosis - increased circulating LPS
Signs and symptoms of insulin resistance
Lethargy (glucose not getting to target tissue)
Hunger
Overweight
Increased hip:waist ratio
Increased blood pressure
Increased cholesterol
Increased blood glucose levels
Acanthosis nigricans
Skin tags
Brain fog
Naturopathic approach to insulin resistance
Stabilise blood glucose levels - reduced carbs, increased protein, increased fibre, Mg, Mn, Zn, B vits, chromium
Reduce inflammation - increase plant food, green tea, prioritise sleep
Optimise insulin sensitivity - TRE, moderate exercise, prebiotics (inulin/FOS)
Nutrients to improve insulin sensitivity
D
Mg
Zn
ALA
CoQ10
Chromium
Cinnamon
What training can be useful for individuals in improving IR?
Blood Glucose Awareness Training
Naturopathic approach to reducing obesity
Smaller portions
Meal composition - low GI
Protein based breakfast
Protein with every meal
Fasting/TRE
Chew food well
Mindful eating
Exercise daily
Which nutrients are often insufficient in obese individuals?
A
C
D
B9
Fe
Zn
Ca
Why isn’t calorie restriction beneficial for reducing obesity?
Triggers several biological adaptations designed to prevent starvation
Decreased leptin levels = increased feeding and reduced energy expenditure
Pre-adipocyte proliferation = increased fat storage capacity
Changes in levels of circulating gut hormones for homeostatic regulation of body weight
Nutrients for reducing obesity
5-HTP
Green tea
L-carnitine
Conjugated linoleic acid
Chromium
Gymnema sylvestre
How does 5-HTP help with reducing obesity?
Increases feeling of satiety
Promotes sleep by enhancing melatonin production
Dosage of 5-HTP to support reducing obesity
50-100mg twice/day
How does green tea help with reducing obesity?
EGCG polyphenol stimulates thermogenesis and fat oxidation
Dosage of green tea to support reducing obesity
600-900mg/day
(3-4 cups of brewed tea)
How does L-carnitine help with reducing obesity?
Beta-oxidation of fatty acids in mitochondria
Improves leptin resistance
Dosage of L-carnitine to support reducing obesity
2000mg/day
How does conjugated linoleic acid help with reducing obesity?
Improves leptin resistance
Improves lipolysis in adipocytes
Dosage of conjugated linoleic acid to support reducing obesity
Up to 3.4g/day
How does chromium help with reducing obesity?
Lowers body weight
Increases lean body mass
May reduce carb cravings
Dosage of chromium to support reducing obesity
200-1000mcg chromium picolate
How does gymnema sylvestre help with reducing obesity?
Helps to lower blood glucose levels
Increased secretion of insulin
Increased utilisation of glucose
Inhibiting glucose absorption from the intestine
How can we break clients’ habits to help reduce obesity?
Identify the cue - what happens at the same time and place every day?
Change the routine
Change the reward
Repetition
