adiposity based chronic disease

body mass index

• obesity defined by BMI

• obesity= BMI > 30

BMI= weight in kg/(height in meter)²

problems with BMI

• doesn’t measure adiposity (body fat)

• doesn’t consider factors like muscle mass and bone density

• doesn’t account for differences across race, ethnicity, sex, and age span

BMI (asian descent)

• higher body fat percentages and more visceral fat at a given BMI compared to euro descent

• higher weight related disease risks at lower BMIs than gen pop.

BMI > 23 kg/m² is considered OVERWEIGHT

waist circumference

assesses body fat distribution

• fat in abdominal area is largely visceral fat

• vis fat linked to metabolic disturbances and increased risk for cardiovascular disease and type 2 diabetes…

obesity

defined by excess adiposity confirmed with

• at least one measure of body size and BMI

• at least 2 measures of body fat regardless of BMI

• direct body fat measurement such as DEXA scan

waist to height ratio (WHtR)

rapidly becoming gold standard for simple health screening

accurate predictor of obesity related cardiometabolic risk factors such as HTN, DM2, ASCVD

keep your waist to less than half your height

WHtR 0.6 or higher

central adiposity: high

health risk: high

WHtR 0.5 to 0.59

central adiposity: increased

health risk: increased

WHtR 0.4 to 0.49

central adiposity: healthy

health risk: not increased

new definition of obesity

adiposity-based chronic disease (ABCD)

prevalence of obesity in US and in world

40.3% obese (all men and women)

9.4% severe obesity (all)

74% of adults in the US were overweight or obese

(age 40-59 highest rates, women highest)

toxic food environment

• easy availability, affordable, energy dense, ultra processed foods and bevs…

• greater tendency to eat outside food

• greater exposure to food cues w/marketing of fat and sugary processed bevs and foods

all contribute to obesity

environment barriers to activity

increased sedentary time

• too much screen time

decreased opportunity for physical activity

• fewer physical demands w/modern tech

• reliance on cars (no walking, biking)

• crime prone areas or neighborhoods without sidewalks (can’t walk outside → obesity)

sleep and obesity

higher risk of obesity and weight gain for those who get little sleep compared to those who get 7-8 hrs a night

biological factors

• in utero environment

• birth weight

• gender and age

• concurrent disease

all contribute to obesity or not

psychosocial risks assoc w/obesity

• depression

• low self esteem

• risk of suicide

• discrimination

• social isolation

endocrine/metabolic risks assoc w/obesity

• type 2 diabetes mellitus

• metabolic syndrome

• polycystic ovary syndrome

musculoskeletal risks assoc w/obesity

• osteoarthritis

• impaired mobility and flexibility

• gout

• lumbar disk disease

• chronic low back pain

cardiovascular risks assoc w/obesity

• hyperlipidemia

• left ventricular hypertrophy

• HTN

• sudden cardiac death

• A-fib…

GI health risks assoc w/obesity

• GERD

• gallstones

• nonalcoholic steatohepatitis

cancer health risks assoc w/obesity

• esophagus

• pancreas

• thyroid

• colorectal

• gallbladder

(endometrial, breast, and ovarian: women)

obesity and metabolic syndrome

increases risk

metabolic syndrome: cluster of conditions that increase risk of CVD, stroke, and type 2 diabetes

1. excess abdominal waist (>40 inch male, >35 inch female)

2. hypertriglyceridemia (>150 triglyceride)

3. low HDL cholesterol lvls (<40 m, <50 f)

4. fasting bg 100 or higher

5. high blood pressure

long term weight loss

losing at least 10% of initial body weight and maintaining that loss for at least 1 yr

peripheral regulation of food intake

orexigenic: factors that increase appetite

• stomach (ghrelin)

anorexigenic: factors that reduce appetite

• adipocytes (leptin), pancreas (insulin), colon (peptide YY), duodenum jejunum (cholecystokinin), duodenum jejunum (GLP-1)

all send signals to hypothalamus

leptin

fat cells produce leptin

• leptin signals brain to suppress appetite and increase energy expenditure

weight gain: leptin levels rise, signal brain to eat less, burn more fat, be active…

weight loss: leptin levels decrease, signals brain to increase appetite and reduce energy use

influences food intake and energy expenditure

ghrelin

empty stomach causes ghrelin levels to rise

• ghrelin signals brain to eat

mesolimbic dopamine system

• hedonic hunger

• when we eat energy-dense foods (sugar/fat), the brain releases dopamine

• in an “obesogenic” environment, this circuit is constantly overstimulated

metabolic adaptation

1. reduced energy expenditure

• when calorie intake drops, body initially burns more calories to compensate for deficit. however, over time, the body adjusts by lowering its resting metabolic rate

2. hormonal changes

• hormones like leptin, ghrelin, and insulin can shift during metabolic adaptation, increasing hunger and reducing satiety

3. increased efficiency

• the body becomes more efficient, storing more fat and burning fewer calories

4. muscle loss

• can further reduce metabolic rate

(results in slower weight loss, and increased risk for weight regain)

weight bias

negative ideologies associated w/excess body weight

weight stigma

thoughts and acts of discrimination toward individuals due to their weight and size, and a result of weight bias

internalized weight bias

when a person applies negative stereotypes (bias) to themselves and engages in self-devaluation

nutrition for weight loss

must achieve a caloric deficit to lose weight

• lose 1-2 lb a week by: reducing daily cals by 500-700 OR eating 1,200 calories (women) and 1,500 (men) xday

• NIH body weight planner

• food diary (myfitnesspal, etc…)

diet for weight loss

• consult w/registered dietician

• focus on eating minimally processed foods

• fruits and veggies

• whole grains, healthy fats, healthy sources of protein in appropriately sized portions

• keep protein intake high to help prevent sarcopenia (loss of muscle mass)

• minimize energy dense foods and bevs (water best)

physical activity

for maintaining and improving health: 150 min mod-intense exercise per week

prevention of weight gain: 150-250 min mod-intense exercise per week

to prevent weight gain after weight loss: 200-300 min mod-intense exercise per week

resistance training

2-3x week essential to reduce sarcopenia associated with weight loss

sleep for preventing obesity

• aim for 7-9 hrs sleep per night

• same wake up and bed time every day

• bedroom dark, quiet, cool

• avoid caffeine and nicotine close to bedtime

• limit heavy meals and alcohol before sleep

• relaxation techniques for winding down

• reserve bed for sleep and intimacy onlu

• manage stress and mental health

• screen for sleep disorders

behavioral interventions for