What is the standard indicator for health status currently?
Body Mass Index (BMI)
How is BMI flawed?
Only measures weight for height, not measuring body fat. Not a good indicator for men!
What is a healthy weight BMI range?
18.5 - 24.9
Overweight BMI? Obese BMI? Morbidly obese BMI?
Overweight: 25-29.9
Obese: 30-39.9
Mor. Obese: Over 40
What are the 3 recommended better indicators of health status?
WC- waist circumference
WHR- waist to hip ratio
WHtR- waist to height ratio
Women have a higher amount of total fat because of the increased essential or storage fat?
Essential, women need 12% for reproductive purposes whereas men only need 3%
Skin fold tests only measure ___ fat.
Subcutaneous (visceral is the more concerning fat deposition)
What are some of the stipulations for using bioelectrical impedence?
Must be well hydrated to conduct electricity
Don’t exercise 4-6 hours prior
No caffeine, alcohol, or diuretics 24 hrs prior
Is fat a good conductor or a poor conductor?
Poor conductor; muscle and organs are good conductors (Basis for bioelectric impedence test)
Underwater weighing is a good measure for body fat but where is it prone to error?
There is always residual air in lungs and GI tract that cannot be accounted for
How does the air displacement test work? (Bod Pod)
Measures the change in pressure due to the volume of person. (Less accurate than underwater weighing)
T/F: DEXA scans are highly accurate and reproducible and there is no exposure risk to patients.
False: DEXA is dual energy x-ray absorptiometry, so there is x-ray exposure
What is our basal metabolism?
Energy we use to breath, regulate body temp and for heart to beat
What is the thermic effect of food?
The energy it takes to digest, absorb, metabolize, and store nutrients of food.
Activity ____ is another way of saying energy expenditure from physical exercise.
Activity thermogenesis
How much of our total energy expenditure is from the thermic effect of food?
10%
What has the highest E expenditure for digestion: carbs, lipids, or proteins?
Proteins (20-30% increased E) Then carbs (5-10% increased E) Then lipids (0-5% increased E)
What accounts for the largest chunk of energy expenditure: Thermic Effect, Basal Metabolic Rate, or Activity Thermogenesis?
Basal metabolic rate = 60-70% of total E expenditure
remember Thermic was 10% and Activity thermogenesis is 20-40%
What equation did we use to estimate resting metabolic rate?
Mifflin- St. Jeor Equation
Leptin stimulates the release of __ ___ ___, a neuropeptide which suppresses hunger.
Melanocyte Stimulating Hormone (MSH)
T/F: Neuropeptide Y stimulates hunger.
True
___, made in the stomach and small intestine, signals hunger.
Ghrelin (think ghrelin=stomach growling)
Leptin, a hunger suppressant, is made where?
Adipose tissue
Cholecystokinin (CCK) and Insulin both __ hunger.
Suppress
Most hunger hormones and neuropeptides bind to what: medulla, hypothalamus, or midbrain?
Hypothalamus
Men require ___ Cal/day for metabolism but women only require ___ Cal/day.
Men-1600 Cal/day
Women-1200 Cal/day
(Any less than that would cause ‘negative E balance’)
Regarding fat deposition, which comes first: an increase in # of fat cells, or an increase in size of fat cells?
Size increases 1st(hypertrophy), then if it exceeds max size, hyperplasia occurs
How does brown adipose differ from white adipose?
Brown has TG stored in multilocular for quick access fuel for thermogenesis. White is unilocular and will release FFA when needed.
Who is likely to have brown adipose and where is it found in the body?
Infants and people native to cold climates.
Stored in cervical and supraclavicular regions
Which (bad) transport protein is produced by adipocytes, and binds HDL & VLDL to initiate a ‘trade’?
Cholesterol ester transport protein (CETP)
What ‘trade’ is initiated by CETP?
VLDL’s TG are given to HDL and HDL’s cholesterol is given to VLDL.
VLDL goes on it’s merry way to return the cholesterol (bad) and HDL goes back to liver and is destroyed (very bad).
In a 2000 study, 25% of our total calories came from what 3 items?
Sweets/desserts
Soda
Alcohol
What is the storage of fat in ADIPOSE tissue leading to negative effects called?
Adipotoxicity
So what is lipotoxicity?
Negative effects of fat being stored in NON-ADIPOSE tissue.
What are the 2 adipokines linked to insulin resistance, & beta cell apoptosis?
TNF-alpha & IL-6
T/F: Leptin resistance is seen in many obese individuals.
True
Why is lipolysis such a bad thing?
Increases the amount of FFA which by themselves are highly inflammatory.
What is the typical male distribution of fat?
Apple shape, (android-type) has more visceral adipose with associated health risks.(Linked to testosterone)
What is the typical female distribution of fat?
Pear shape, (gynoid-type) is associated with estrogen and accumulates fat at hips, butt and thighs.
For men to lose visceral fat, they only need to change ___. But for women to lose visceral fat, they must ___ and ___.
Men: Diet alone
Women: Diet and Exercise
Which is easier to lose: subcutaneous or visceral fat?
Visceral
What are the 3 conditions associated with metabolic syndrome?
Dyslipidemia, insulin resistance, hypertension
95% of those with eating disorders are in what age range?
12-25 y.o.
T/F: Eating disorders have the highest mortality rate of any mental illness.
True
What are some notable features of anorexia nervosa?
Marasmus (wasting appearance), amenorrhea (3 consec. menstrual cycles MIA), lanugo (fine hair on face & arms), restricted eating behaviors…
What is bulimia nervosa?
Binge-purge behavior associated with self-image issues
How many times do you need to binge-purge before classified as bulimia nervosa?
At least 2 times a week for 3 months
Is amenorrhea associated w/ bulimia nervosa?
No, but usually has irregular menses
T/F: Bulimia nervosa will have more GI issues because of all the purging and usually have a marasmus appearance similar to anorexia nervosa.
False: GI part is true but bulimia individuals will actually be normal to slightly overweight due to the absorption from the binge phase, even though they purge later.
What is pica?
Pattern of eating non-food materials when we know better (over the age of 18 months)
About 50% of all eating disorders are considered ___ ___.
Disordered eating
What is the female athlete triad?
Osteoporosis
Amenorrhea
Disordered eating
Patients w/ female athlete triad often develop stress fractures due to low what?
Low estrogen levels
What would indicate a healthy waist to height ratio?
WHtR: Less than 0.5
What is a healthy waist to hip ratio for men and women?
WHR: Men: Less than 0.95
Women: Less than 0.8
What is a healthy waist circumference for men and women?
Men–> Less than 40”
Women–>Less than 35”
Which hormone is responsible for the feminization of overweight males by converting testosterone into estrogen?
Aromatase
