Lecture 10 Flashcards
body composition
proportions of muscle, bone, fat and other tissue that make a persons total body weight
- more important to health than controlling body weight
when are underweight people at risk?
- when food is scarce
- when hospitalized
- when fighting a wasting disease
problems associated with underweight
- undernutrition
- osteoporosis
- infertility
- impaired immunocompetence
underweight people benefitting from gaining weight due to…
- energy reserve
- reserves of nutrients that can be stored
problems associated with overweight/obesity
- hypertension
- T2D
- dyslipidemia
- CHD
- gallbladder disease
- sleep apnea
- certain cancers
other risk factors for disease other than body weight
- genetics
- smoking
- cardiovascular fitness
types of cancer overweight and obesity increases the risk of?
- esophageal
- liver
- kidney
- stomach
- colorectal
- advanced prostate
- post-menopausal breast
- gallbladder
- pancreatic
- ovarian
- endometrial
what diseases are more common in those with obesity?
hypertension, diabetes, and heart disease
moderate weight loss
reduces risk of diseases related to overweight and obesity
central obesity
may increase risk of death from all causes as compared to fat elsewhere in the body
vicceral fat (intra-abdominal fat)
fat stored within the abdominal cavity in association with internal abdominal organs
results of visceral fat
increased risk of…
1. diabetes
2. stroke
3. hypertension
4. coronary artery disease
subcutaneous fat
fat just below the skin
ex. abdomen, thigh, hips, legs
what shape do those with central obesity have?
apple shape
who are more likely to have an apple shape?
- postmenopausal males and females
- smokers
- those with moderate-to-high alcohol intake
- physically inactive
what shape do those who have subcutaneous fat have?
pear shape
who are more prone to a pear shape?
females are more prone to carrying fat around the hips and thighs prior to menopause
how is bodyweight/body fat assessed?
BMI (body mass index) kg/m2
what does BMI correlate with?
degree of body fatness and disease risk
waist circumference
amount of visceral fatness
disease risk profile
- hypertension, diabetes, high cholesterol
- more risk factors and greater obesity, the more important controlling body fatness becomes
- greater the body fatness and the higher the disease profile, the greater the risk
how do you calculate BMI>
weight (KG)/height(M2)
BMI of 30 or over
obese
BMI 30-34.9
Obese class I
- high risk
BMI 35-39.9
Obese class II
- very high risk
BMI >or = 40
Obese class III
- extremely high risk
limitations to BMI
- no indication about how much of weight is fat
- no indication of location of body fat
what is BMI not appropriate for?
- athletes
- pregnant and lactating women
- adults over 65
- different races
- <18 years old
what were BMI values originally based on?
people under 65 who were primarily white europeans and americans
problems associated with underweight
- undernutrition
- osteoporosis
- infertility
- impaired immunocompetence
why is waist circumference a good measure?
most practical indicator of fat distribution and abdominal fat
waist circumference that increase risk are… (Health Canada)
102 cm for males
88 cm for females
- a WC just below these values should also be taken seriously
Heart and stroke foundation
Males:
- more than 94 cm increased risk
- more than 102 cm substantially increased risk
Females:
- more than 80 cm increased risk
- more than 88 cm substantially increased risk
greatest risk associated with WC and BMI
- WC of >102 cm (m) or >88 cm (f)
- BMI = obese class I and up
cardiovascular fitness benefits
improves health and longevity independent of BMI
lowest risk of death from chronic diseases
seen in normal weight fit people
people with elevated BMIs (social and economic costs)
- judged on appearance
- less often hired
- pay higher insurance premiums
- less often admitted to Universities and Colleges
society and overweight
- society places enormous values on thinness
- unjust stereotypes of those with excess weight
- prejudice and hostility can have an emotional toll
- weight bias and obesity stigma = a problem
weight bias
refers to negative attitudes and views about obesity
weight stigma
social stereotypes and misconceptions about obesity
stereotypes about people with obesity
lazy, awkward, sloppy, non-compliant, unintelligent, unsuccessful , lacking self-discipline or self-control
weight discrimination
- result of weight bias and obese stigma
- when we treat people with obesity unfairly
operational definition of obesity
BMI exceeding 30kg/m2 and subclassified into 3 classes
definition of obesity
a chronic disease in which abnormal or excess fat impairs health, increases long term medical complications and reduces lifespan
edmonton obesity staging system (EOSS)
-5 stage system of obesity classification
-considers metabolic, physical, and psychological parameters in order to determine optimal treatment
-better predictor of mortality than BMI
EOSS stage 0
-no apparent risk factors, physical symptoms, paychopathology, limitations or impairment of well-being related to obesity
EOSS stage 1
-presence of obesity related subclinical risk factors, mild physical symptoms & psychopathology, mild limitations/impairment of well-being
EOSS stage 2
presence of established obesity-related chronic disease, moderate limitations
EOSS stage 4
severe diability from obesity-related chronic diseases, severe disabling psychopathology, severe limitations and impairment
CPGS reccomendations to reducing weight bias in obesity
- healthcare provides assess own attitudes
- healthcare providers recognize weight bias affects behavioural outcomes
- healthcare providers avoid making assumptions
- healthcare providers avoid using judgemental words
CPGS recommendations for indigenous
healthcare providers should:
-engage patient with reality
-validate patient experienes
- advocate for access
-help patients recognize good health is attainable
-self-reflect on anti-indigenous setiment
what happens when more food energy is consumed than needed
excess fat accumulates in the fat cells of bodys adipose tissue
how many Kcal adds one pound of body fat
3500kcal
daily energy balance
change in energy stores= energy in - energy out
weight maintenence
energy in. = energy out
energy in
food and beverage
energy out
lifestyle & metabolism
finding the energy content of foods
-burn food in a bomb calorimeter
-when food burned, energy released in form of heat
-overstates amount of energy the human body gets so equn used to adjust
what is produced from burning food in bomb calorimeter
-CO2 and H2O are produced
-the amount of oxygen given an indirect measure of heat produced
Kcals according to the macronutrient & alcohol
1g carb = 4kcal
1g protein = 4kcal
1g fat = 9kcal
1g alcohol = 7kcal
types of energy output
-basal metabolism
-voluntary activities
-thermic effect of food
basal metabolism
-energy expended on all involuntary activities needed to sustain life
-excludes digestion and voluntary activities
-lowest during sleep
-varies
voluntary activities
-intentional activities
-most variable element of energy output
-very changeable
thermic effect of food
-5-10% of meals energy is expended in stepped-up metabolism following a meal
diet-induced thermogenesis
-Eating; GI tract muscles speed activity producing heat
-TEF is total amount of energy needed to digest, absorb, metabolize and store the food you eat
TEF is influecned by
-meal size
-meal frequency
-meal composition
specific thermic effect of food for macronutrients and alcohol
fat = 0-5%
carbs = 5-10%
protein = 20-30%
alcohol = 15-20%
BMR short and long term effects of physical activity
short term PA will not increase BMR, long term PA will increase BMR
**lean tissue has higher BMR than fat tissue
BMR is higher in:
-younger people
-taller people
-people who are growing
-people with more lean muscle mass
-fever
-during stress
-environmental temperature -adjusting to heat and cold
-hyperthyroidism
BMR is lower in
-older people (lean body mass decliens with age)
-fasting
-malnutrition
-hypothyroisism
Restimg Metabolic Rate (RMR)
-a measure of energy use of a person at rest in a comfortable setting but with less stringent criteria for food intake and PA
energy estimate requiremets (EER) (calories needed per day)
males: kg body weight x 24 = kcal/day
females kg body weight x 22 = kcal/day
EER often include
-age
-sex
-physical activity
-body size & weight
ways to measure body composition and fat distribution
-anthropometry
-density
-conductivity
-radiological techniques
measuring via anthropometry
fatfold measures - caliper
measuring via density
underwater weighing or air displacement plethysmography
-lean tissue is denser than fat tissue
measuring via conductivity
bioelectrical impedance
measuring via radiological techniques
DEXA
percent of body fat should generally be:
males: 12-20%
females: 20-30%
for 18-39 year olds
how much body fat is ideal for health
-depedns on sex, age, lifestyle,stage of life
