8. OBESITY & EATING DISORDERS Flashcards
This module covers: • Obesity • Key drivers of obesity. • Adipose Tissue. • Appetite and satiety. • Insulin resistance. • Reducing obesity. • Changing eating behaviours. • Eating Disorders • Anorexia Nervosa. • Bulimia Nervosa. • Binge Eating Disorder.
Define overweight/obesity. What BMI is considered overweight and obese?
Overweight and obesity are defined as abnormal or excessive fat accumulation that presents a risk to health.
A body mass index (BMI) over 25 is considered overweight, and over 30 is obese.
Dietary guidelines suggest that calorie deficit needs to be in the range of ____ kcal daily for an adult to lose weight.
500‒750
How can exercise help with obesity?
Exercise increases cellular AMPK, increasing GLUT 4 activation, glucose uptake and mitochondrial activity with enhanced ATP production.
Explain how sleep disruption may be a driver for obesity.
Give recommendations on how to improve sleep.
Sleep disruption creates a hormonal imbalance in the body that promotes overeating and weight gain:
● Associated with reduced glucose tolerance and insulin sensitivity.
● Disrupts the balance of ghrelin and leptin with increased ghrelin levels promoting hunger and unhealthy food choices.
● Proposed that inflammatory pathways may be activated by insufficient sleep contributing further to obesity.
Sleep hygiene:
- Epsom salt baths
- avoid Blue Light
- deal with root cause of sleeplessness
- stress management
- Magnesium and B6
- valerian, vervain, chamomile or passionflower teas
- Rescue Remedy Night Spray;
- lighting
- natural fibres etc
Drivers of Obesity
Explain how shift work, sleep deprivation and exposure to bright light at night increase the prevalence of adiposity. Provide recommendations to clients on night shift.
- Shift work is associated with obesity, dysregulation of triglycerides and cholesterol, abdominal obesity, T2DM and CV disease.
- Irregular eating patterns are associated with weight gain and obesity. Late-night eating causes higher peak post-prandial glucose levels, reduced lipolysis, circadian rhythm misalignment, together with microbial dysbiosis.
With clients on night shift try to adhere to a regular eating pattern, whether on day or night shifts.
Avoid eating sweets / caffeine on nights as much as possible; look to nourishing snacks.
Name THREE strong dopamine stimulators. What does the food industry use to create a ‘Bliss Point’ to maximise dopamine release?
Strong dopamine stimulators (fat, starch, salt, free glutamate, alcohol, caffeine) activate rewarding brain circuits to trigger anticipatory cravings for ‘more’.
Reward value and palatability of food can override satiety signals. The food industry combines fat, sugar and salt to create a ‘Bliss Point’ to maximise dopamine release.
Drivers of Obesity
What are the implications of consuming artificially sweetened drinks including high fructose corn syrup?
Artificially sweetened drinks have a 47% higher risk of increasing BMI. High fructose corn syrup (HFCS) has a strong association with obesity, NAFLD and metabolic syndrome.
Drivers of Obesity
Explain how long-term high cortisol exposure plays a major role in the development and maintenance of obesity.
Cortisol levels (overactive HPA axis) are elevated in obese individuals and associated with enhanced abdominal fat deposition.
Factors influencing HPA axis include:
- high GI consumption
- chronic stress
- chronic pain
- alcohol
- chronic sleep deprivation
- night eating syndrome
Stress can alter eating behaviours for 80% of individuals of which 50% consume more food. Stress enhances preference for energy-dense ‘comfort foods’.
Drivers of Obesity
Explain the connection between a disrupted microflora, obesity and diabetes. The lack of what strain has been linked with obesity?
- ‘Traditional’ gut flora produces carbohydrate-active enzymes to digest complex polysaccharides as found in plant fibre.
- A by-product is production of SCFAs, used as fuel by intestinal cells.
- The low plant fibre content of an industrialised diet has shifted gut flora towards mucus-utilising bacteria.
- Lack of Akkermansia muciniphilia has been linked with obesity. This can contribute to a damaged mucosal barrier ➝ metabolic endotoxaemia ➝ disrupted insulin signalling and low-grade inflammation.
Drivers of Obesity
Explain how genetic factors play a role in obesity.
- SNPs in the fat mass and obesity-associated FTO gene is a strong predictor of obesity.
- VDR SNPs play a role in obesity associated with ongoing inflammation. This may be due to altered gut permeability and microbial translocation.
- Mutations in the ADIPOQ gene are associated with adiponectin deficiency which may predispose to metabolic disruption.
- Polymorphisms in the SLC2A2 gene are associated with increased habitual sugar consumption and a predictor of T2DM.
Knowing your client’s genetic profile may be helpful in understanding the predisposing environment.
TRUE or FALSE
Adipose tissue is inert tissue that stores fat.
False.
Adipose tissue (AT) is a metabolically active organ which regulates whole-body energy homeostasis. AT changes in quantity and distribution with age.
Adipocytes and other adipose tissue cells produce lipids, steroids, inflammatory cytokines and peptide hormones (e.g. leptin).
Discuss various types of adipose tissue:
- white (incl. subcutaneous and visceral)
- brown
- beige-white
- White adipose tissue (WAT): Long-term energy storage.
-Subcutaneous adipose tissue (SAT): Situated under the skin.
-Visceral adipose tissue (VAT): Intra-abdominal.
↑ number and size of adipocytes = WAT expansion = obesity. - Brown adipose tissue (BAT): Abundant in early life.
- Beige-white adipose tissue: Similar actions to BAT.
What is adipocyte hyperplasia and hypertrophy? What diseases are they associated with?
With persistent energy surplus, white adipose tissue can continue to grow.
Chronic energy imbalances with increased storage results in increased adipocyte numbers (hyperplasia) and size (hypertrophy).
Hypertrophy is strongly associated with dyslipidaemia, IR, T2DM and NAFLD. Hyperplasia tends to be associated with fewer serious health effects.
Satiety is the physiological state at the end of a meal when further eating is inhibited by ‘fullness’. Name THREE factors involved in satiety.
- Mechanical stretch of the stomach via the Vagus nerve.
- Adipocyte hormones: Ghrelin, leptin and adiponectin.
- Hormones and peptides: Glucagon-like peptide (GLP-1) and cholecystokinin (CCK).
- Neuropeptides and neurotransmitters: Neuropeptide Y (NPY), Agouti-related peptide (AGRP), serotonin.
- Other hormones such as thyroid hormones, oxytocin, cortisol, insulin and glucagon and neurotransmitters (e.g., dopamine and serotonin) also play a role in appetite regulation.
What is leptin and its function?
Leptin is a ‘satiety’ hormone produced by adipocytes:
- Acts as a signalling factor from adipose tissue to the CNS, regulating food intake and energy expenditure.
- Released during the day.
What is leptin resistance and how does it develop?
Leptin resistance (LR) is a reduced sensitivity or failure of response in the brain to leptin.
- Leptin acts on the leptin receptor in the hypothalamus.
- In obesity, leptin levels are high but cannot function due to leptin resistance. Over time this leads to changes in metabolism, abdominal weight gain, chronic fatigue, sleep dysregulation, metabolic diseases.
↑ adipose tissue = ↑leptin resistance.
Name FOUR ways to break the cycle of leptin resistance.
- Exercise.
- Fasting.
- Macronutrient balance.
- Restore sleep.
What is the function of ghrelin?
Ghrelin functions as an appetite-stimulating signal.
- Plays a role in the long-term regulation of energy metabolism and the short-term regulation of feeding - increasing food intake and body weight.
- ↑ before a meal and ↓ to lowest levels within 1 hour of eating.
- In obesity, we usually see ↓ ghrelin, but a reduction in body weight ↑ ghrelin (hunger associated with dieting).
What factors influence ghrelin?
- age
- sex
- BMI
- glucose
- insulin
- sleep
What is adiponectin and its role? What are its reduced levels associated with?
Adiponectin is the most abundant circulating adipokine.
- Increases glucose uptake and β-oxidation of fats.
- Increases insulin sensitivity.
- Anti-inflammatory.
Reduced adiponectin is associated with IR, T2DM, obesity and CV disease.
BMI and visceral fat are significant predictors of plasma adiponectin levels.
A low adiponectin : leptin ratio (a sign of dysfunctional adipose tissue) may increase oxidative stress and inflammation.
How can we boost adiponectin levels naturally?
- blueberries (anthocyanidins)
- turmeric (curcumin)
- omega-3
- 40–50 grams fibre per day
- green tea (catechins)
- cold water therapy
- daily HIIT.
Name FIVE causes and risk factors of insulin resistance
- High oxidative stress, e.g., poor sleep, environmental toxins.
- Reduced physical activity - exercise modulates inflammatory mediator expression involved in IR and increases GLUT4 expression.
- Chronic stress - ↑ glucose, lipids and inflammatory cytokines.
- Mitochondria dysfunction - ↑ ROS, low ATP, ↓ GLUT 4.
- Poor methylation (high homocysteine), hypertension, elevated triglycerides. Low adiponectin.
- Dysbiosis - drives the inflammatory process with ↑circulating LPS.
Name SIX signs and symptoms of insulin resistance
- Lethargy.
- Hunger.
- Brain fog.
- Overweight.
- ↑ Waist to hip ratio.
- ↑ blood pressure.
- ↑ cholesterol & ↑ triglycerides.
- ↑ blood glucose levels.
- Acanthosis nigricans.
- Skin tags.
Naturopathic approach to insulin resistance
Provide dietary/lifestyle recommendations and supplements to stabilise blood glucose levels
- Macronutrient balance: Reduced carbohydrates, increased protein, increased MUFA.
- Protein-based breakfast - helps normalise insulin secretion.
- ↑ Fibre - slows gastric emptying, slower release of glucose and therefore ↓insulin response.
- Calorie restriction as appropriate.
- Avoid processed food with artificially engineered palatability - incl. sugar and sweeteners.
- Stress management techniques - when stressed people can turn to hyper-palatable comfort foods such as fast food and snacks.
- Magnesium, manganese, zinc, B vitamins, chromium etc.
Naturopathic approach to insulin resistance
Provide dietary/lifestyle recommendations and supplements to reduce inflammation
- Avoid inflammatory foods - refined carbs, damaged fats etc.
- Increase a rainbow of plant foods incl. blue, purple, black foods.
– Proanthocyanidins modulate inflammation, enhance anti-inflammatory adiponectin and support microbiome: ginger, turmeric, flaxseeds, tea, apples, berries.
– Green tea polyphenols ↓ fasting glucose and ↓ HbA1c.
– Foods rich in prebiotic fructans, fructooligosaccharides (FOS), inulin e.g., chicory, leeks, onions, Jerusalem artichokes. - Antioxidants (α-lipoic acid, glutathione etc).
- Prioritise sleep - sleep deprivation can increase C-reactive protein.
Naturopathic approach to insulin sensitivity
Provide dietary/lifestyle recommendations and supplements to optimise insulin sensitivity
-
Meal timing and frequency is key to ensure appropriate insulin and glucagon secretion.
- Time Restricted Feeding (TRF); elimination of snacks.
- Eat last meal earlier in the evening then fast overnight.
- Increase moderate exercise - ↑ insulin sensitivity by acting directly on muscle metabolism.
- Prebiotics - inulin and FOS have been shown to modulate appetite, blood glucose and insulin levels.
- Vitamin D, magnesium, zinc, α-lipoic acid, CoQ10, Chromium, Gymnema sylvestre, cinnamon, bitter melon, fenugreek, garlic.
Provide SIX recommendations to address over-eating
- Smaller portions - eat from a side plate vs. a dinner plate.
- Protein-based breakfast - eating a protein-based breakfast helps normalise insulin secretion and reduces the tendency to snack.
- Protein with each meal - palm size.
- Keep meals simple - the variety of foods in a meal increases intake: The more foods differ in their flavour, the greater the boost.
- Leave 4 hours + between meals. Fasting or a fasting window such as 16:8.
- Chew food well - 30 times.
- Turn off all ‘stimulators’ whilst eating.
- Mindful eating - enjoy the ritual of food vs. ‘food to survive’.
Despite excessive dietary consumption, obese individuals often have insufficient intake of what nutrients?
- vitamin A
- C
- D
- folate
- iron
- zinc
- calcium
Strategies for stimulating fat loss
- Meal composition - educate, e.g. low GL; macronutrient balance.
- Breakfast is vital and should include protein and only low GL carbs.
- Protein at each meal - increases postprandial thermogenesis.
- Exercise daily - 35 minutes low intensity.
- Food diary and frequent practitioner contact.
TRUE or FALSE
Calorie counting is essential for a weight loss programme.
False
Calorie counting can often be demeaning to the client and it doesn’t always help with healthy food choices. Instead, evaluate if the food advice meets their minimum requirements and does not exceed a maximum amount, or else it will not work.
NOTE: Diets are for the short term, people often ‘fail’ and gain back what they lost quickly plus more. Lifestyle change is slower, it has health as its goal - a journey, not a destination.
What biological adaptations are triggered by caloric restriction to prevent starvation?
- ↓ leptin levels during weight loss signals to the brain ↑ feeding and ↓ energy expenditure.
- Pre-adipocyte proliferation occurs, ↑ fat storage capacity.
- Changes occur in the circulating levels of several gut hormones involved in the homeostatic regulation of body weight.
- These adaptations are often potent enough to undermine the long-term benefits of lifestyle modification, particularly in an environment replete in highly-calorific foods.
Nutrients for weight loss (dosage and function): 5-Hydroxytryptophan 5-HTP
Dosage: 50-100 mg twice daily.
Start at a lower dose; build up to minimise possible nausea.
- 5-HTP can aid weight loss by increasing feelings of satiety.
- Promotes sleep by enhancing melatonin production.
- Has free radical scavenging activities.
Nutrients for weight loss (dosage and function): Green Tea
Dosage: 600–900mg / daily (~3–4 cups of brewed green tea).
- Green tea polyphenols * may stimulate thermogenesis and fat oxidation.
* especially EGCG (the major catechin found in green tea)
Nutrients for weight loss (dosage and function): L-Carnitine
Dosage: up to 2000 mg / daily.
- For β-oxidation of fatty acids in mitochondria.
Essential for efficient utilisation of fats for energy. - Improves leptin resistance.
- In studies L-carnitine supplementation significantly reduced body weight, BMI, and fat mass.
