Unit 8: Weight Management Flashcards
What are the 2 things involved in proper weight management?
- healthy relationships w/ food + physical activity
- psychological + environmental control
What are the 3 types of body fat? Describe each.
- Visceral fat: fat embedded within mesentery (tissue that connects intestines to back of the abdominal wall) surrounding the abdominal organs
- Subcataneous fat: fat located just beneath the skin (80% of all fat)
- Ectopic fat: fat located on/within organs (increases risk for metabolic syndrome + CVD)
Energy Balance
Explain the concept of energy balance
- your body uses calories to maintain vital body functions
energy input - energy output = +/- energy balance
Energy Balance
Describe the concepts of energy in and energy out
state percent value of each type of energy out source
energy in: food
- carbs, fats, proteins, vitamins, minerals
energy out
basal metabolism (60-75%):
- heart rate, nerve signals, brain activity
- mostly determined by genetics
- around 10x weight in lbs
- higher lean mass
thermogensis (10%):
- heat that is produced in result of processing food
physical activity (15-30%):
- those who are more active have higher %
Explain what drives energy intake
3 points
hunger: need to eat (physiological)
- can influence appetite
appetite: desire to eat (not always physiological)
- influenced by sight, smell, thought
- gene variation specific
satiety: fullness (physiological)
- can be influenced by genes
- influenced by eating voluminous food and eating slowly
- takes 20 min for brain to receive message of fullness
discuss different methods of assesing body weight + composition
7 methods
Height-Weight charts: list range of ideal/recommended body weight associated w/ lowest mortality rate for people of same sex, age + height
- easy to use, highly inaccurate for some, indirect measure of body fat
BMI: Body Mass Index
- doesn’t differ between body fat + lean mass
- simplest + most broadly applicable
- measure in weight (kg)/(height(m))²
Hydrostatic Weighing: under H2O, helps measure body fat %
- expensive
Skinfold measurements: measure # of fat to pinch
- sometimes inaccurate
- cheaper
Circumference measurements: around hip bones/navel area + BMI
Electrical Impedence: measure H2O in body to determine fat
Scanning: fairly accurate
Explain the health risks associated with excess body fat
obesity reduces life expectancy by up to 20 years
- causes 1/10 premature adult deaths
associated with increase risk of CVD + diabetes
- plus cancers, impaired immune function, diseases of kidney + gallbladder, bone + joint disorders, incontinence, pregnancy + psychological disorders
Explain genetic factors to excess body fat
nutrigenomics - how nutrients + genes interact
- genetic variations can cause people to respond differently to nutrients
50 genes associated w/ obesity
plays a role, but so does lifestyle
Explain physiological factors to excess body fat
metabolism
- RMR, accounts for 60-70% of DEE
hormones
- leptin appears to let brain know how small or big body’s fat sorages are - regulating appertite + metabolic rate
- ghrelin, increases appetite - influenced by sleep, whole grains + proteins
fat cells
- the # of adipose tissue that the body can store is a function of # + size of fat cells
- fat cells are compartments that can inflate to hold body fat
- when they are filled, body makes more
Differentiate visceral VS subcutaneous fat
Visceral
- contains chemicals that adhere to blood vessel lining, cause insulin resistance + CVD
- considered an active endocrine organ
- hard
Subcutaneous
- little to no health risk
- soft + flabby
- found in more W than in M
Location of Fat Cells
Explain the traits gynoid obesity and android obesity
Which is better in terms of health risk?
Gynoid obesity
- when subcutaneous fat appears on lower body
- described as pear shape
- appears more in women than men
Android obesity
- excess visceral and ectopic fat carried in upper body
- described as apple body shape
Apples are bad, pears are good.
Explain the lifestyle factors that contribute to excess fat
eating
canadians have access to plenty of calorie-dense foods, resulting in eating habits that contribute to weight gain
- fast food, packaged + convenience foods
- restaurant + convenience food protions are large
physical activity
- activity levels are declining
sleep
short sleep duration associated w/ increased BMI and abdominal obesity
Explain our obesogenic environment
- promotion of overconsumption of calories while discouraging physical activity
- food industry promotes sale of high-calorie processed foods
- obesogens (EDCs): endocrine disrupting chemicals, found in cosmetics, plastics, lubricants, shampoos, pesticides + paints
- thought to disrupt body’s control over fat production
Explain psychosocial factors to excess body fat
- many people have found use of food in coping w/ stress + negative emotions
- strongly associated w/ socio-economic status, prevalence of obesity reduces as income increases
Eating Disorders
What is an eating disorder?
What percen of it is made up of females? Males?
a serious disturbance in eating patterns or behaviours, characterized by a negative body image
- among teens, 50% of females, 30% of males have disordered eating behaviours
Eating Disorders
Describe Anorexia Nervosa
Risks?
most common, leading mortal psychiatric disorder
- intense fear of gaining weight: do not eat enough to maintain adequate body weight
- associated with distorted body image, feeling that food is enemy
- purging/over exercising
Risks
- amennorrhea
- intolerance to cold
- low bP
- CVD, GID, encorine + skeletal disorders
Eating Disorders
What is purging?
use of vomiting, laxatives over exercising, restrictive dieting, enemas, diurectics or diet pills to compensate for food that has been eaten
Eating Disorders
Describe Bulimia Nervosa
Risks?
2nd most common
- episodic binge-eating followed by purging
- binging, often thousands of calories in secret
- feeling ashamed, digusted + fearful of weight gain
- also can be lack of food, so compensate by binge eating
Risks
- erosion of tooth enamel
- damage to esophagus
- dehydration
- kidney, liver, heart damage
- depression
Eating Disorders
Describe Binge-Eating Disorder
- uncontrollable eating, followed by guilt + shame w/ weight gain
- more associated w/ obesity
Eating Disorders
What are treatments for eating disorders?
Anorexia: averting crisis by restoring body weight
- addressing psychological issues
Bulimia + Binge-Eating: stabilizing eating patterns; identifying + changing behaviours that led to disordered eating
Unit 8 Quiz Questions
T/F: a body mass index of 28.5 is classified as normal wieght
False
Unit 8 Quiz Questions
T/F: the skinfold measurement technique for determining body fat composition involved measuring fat found under the skin
True
Unit 8 Quiz Questions
T/F: overfat is a more accurate term than overweight when describing the condition of having too much body fat
True
Unit 8 Quiz Questions
T/F: Hormones play no significant role in teh accumulation of body fat
False
