lecture 8: energy balance and healthy body weight Flashcards
BMI
(Weight in KG) / (Height in M)^2; ex., 63.5kg / (1.66m)^2 = 23 BMI
Inherently only reflects height and weight, not body composition
Tends to have a correlation with body fatness unless you’re a bodybuilder
Exceptions*: People who are lean and healthy, very muscular people, people who are <18 and still growing, pregnant women/lactating women, those who are 65+ (27-32 could be okay)
underwight
less than 18.5
healthy BMI
18.5-24.9
overweight
BMI 25-29
obese
BMI 30+
class 1: 30-34
class 2: 35-39.9
class 3: 40+
an epidemic those who are overweight/obese
61.8% men, 46.2% women*****
problems w obesity***
Type 2 Diabetes
Dyslipidemia (abnormal cholesterol; high LDL, low HDL)
HTN, Coronary heart disease
Gallbladder disease
Sleep Apnea
Certain cancers
central obesity
Central Obesity: Fat collecting deep within central abdominal area (visceral fat); ex., people with big stomachs but rock hard abs: it’s because it’s mixed around under the organs vs. subcutaneous pooch
Generally can be determined if you measure waist circumference as well
Increased risk of diabetes, stroke, HTN, CVD, death
apple vs pear shaped
apple shape obesity
Greater risk in men, postmenopausal women, smokers, alcoholics (beer belly)
Keynote feature of central obesity; Can be reduced with physical exercise
pear shape
Women in reproductive years with hips and thighs
waist circumference**
Reflects degree of visceral fatness, most practical indicator* of fat distribution
Where you take it depends on organization; pretty much the same
Take a deep breath then let it out (can’t suck in)
Health Canada: 102cm for men, 88cm for women = increased risk*
Heart and Stroke:
Men: 94cm+ = increased, 102cm+ = substantially increased risk*
Women: 80cm+ = increased, 88cm+ = substantially increased risk*
waist-hip ratio?
gives no more information, benefit, rism than just waist***, useless xtra work
ideal fatness range
12-20 for men, 20-30% for women
Edmonton Obesity Staging System*
This assumes they’re already obese (30+ BMI)
Stage 0: Obese but no risk factors like BP, dyslipidemia, fasting glucose, symptoms
Stage 1: Subclinical, borderline risk factors
Stage 2: Established Diseases related to obesity: HTN, Type 2 Diabetes, Sleep apnea…
Stage 3: Organ damage related to obesity: Heart attacks, strokes…
Stage 4: Severe end-stage disabilities related to obesity; debilitation, impairment, limitations
Know the basics of each of these (none -> signs -> disease -> damage -> 2x damage)
Energy In:
Foods and drinks that you intake; the calories taken in
Any extra calories taken in are stored as Fat; roughly 3500kcal/lb of fat
Energy Out:
Lifestyle and metabolism; percents vary day to day
Basal Metabolism: Sum total of energy expended on all involuntary activities needed to sustain life except for digestion - heartbeat, breathing, skin maintenance
Physical Activities: All voluntary activities and variable element of energy output
Thermic Effect of Food: 5-10% of a meal’s energy is expended while digesting food
Protein has the highest thermic effect of food
Hunger:
Unpleasant/painful sensations that signal a need for food
Roughly 4-6 hours after eating a meal when stomach, SI empties and stomach hormone ghrelin is released but there are MANY more factors
Bloodstream nutrients, meal composition, weather, exercise, hormones, illness
appetite
no hunger, but desire to eat