Final (everything but MT2) Flashcards
what is the energy balance equation
output>input = negative balance; weight loss
input>output = positive balance; weight gain
What is energy input
calories that or body gets from foods we eat
what are the 3 main macronutrients that are sources of energy
4kcal/g for carbs
4kcal/g for protein
9kcal/g for fats
(alcohol can also be a source, @7kcal/g)
What are some factors that affect energy input
neuroendocrine factors (hormones, neurotransmitters, etc like leptin)
filling/distention of stomach
social/psychological factors
food availability/appeal
genetics
What happens when there is a lack of leptin?
sends satiety signals to stop eating; lack of leptin leads to weight gain
What is satiety
neural state that leads to stopping of food intake (things like loss of desire to eat, is the opposite of hunger)
What is hunger
physiological drive to eat
what is appetite
psychological desire to eat (more conditional than hunger)
What are some hormones that impact the energy balance
Leptin - lowers food intake
NPY (neuropeptide Y) - increases food intake
Ghrelin - increases food intake
PYY (peptide YY) - lowers food intake
CCK (cholecystokinin) - lowers food intake
apoA IV (apolipoprotein A4) - lowers food intake
How does the hypothalamus impact hormones and neural signals in relation to energy balance
is the central integrator of circulatory signals (hormones)
Describe the pathway of PYY
digestion of food stimulates PYY and CCK production, resulting in the hypothalamus lowering NPY activity to increase satiety
Describe the pathway of leptin
as nutrients are stored in fat cells, leptin release is stimulated that signals the hypothalamus to lower NPY activity
describe the pathway of ghrelin
an empty stomach secretes ghrelin, which signals to the hypothalamus to increase the activity of NPY, while the fat cells stop secreting leptin
What are the 3 ways energy is outputed
REE - resting energy expenditure (65% of total output, minimum calories used by the body to maintain homeostasis)
TEF - thermic effect of food (10%, acute rise in energy use after meal, influenced by the meal size and macronutrient composition)
PA - physical activity (25%, highly variable)
WHat is BMI
measure of weight (kg)/height (cm squared)
what are two ways to measure Bodyfat
skinfold thickness
underwater weight
WHat is lean body mass (LBM)
body muscle
what is fat free mass (FFM)
LBM + water/minerals
What are the BMI ranges?
under 18.5 - underweight
18.5-24.9 - normal (lowest mortality risk from 21-24)
25-29.9 - overweight
30-34.99 - obesity1
35-39.9 - obesity 2
over 40 - obesity 3
Why is there a large increase in obesity over the last few decades?
high availability of high energy foods
lower physical activity
how many canadians are overweight
1 in 3
how many canadians dont get enough exercise
8 in 10
WHat are the 2 circumference measurements
waist to hip ratio - good indicator of obesity and co-morbidities
waist circumference - if larger than 100cm for men and 90 cm for women, 50% of this population have health problems related to metabolic syndrome which is a combination of the following three
-atherogenic dyslipidemia (high cholesterol
-hypertension
-high blood glucose
What are the 2 types of fat
essential - around vital organs and breasts in women (3% in men, 12% in women)
Storage - non essential fat that can be mobilized for energy
How is fat distributed
visceral - intra abdominal and associated with metabolic syndrome (men usually have more)
Upper subcutaneous - (apple shaped, high waist-hip ratio)
lower subcutaneous- (pear shaped)
WHat are some health risks with obesity (BMI>30)
-type 2 diabetes
-hypertension
-heart disease & stroke
-cancer
-joint disease (e.g., knee)
-INFLAMMATION chronic low-level….contributes to increased risk of some cancer
WHat is white adipose tissue
fat/energy storage
what is brown adipose tissue
regulatory functions and energy balance (heat production)
how do adipocytes grow
hypertrophy and hyperplasia, with weight loss the cell size decreases but not the number
How is fat mobilized in the body
Hormone sensitive lipase mobilizes TG into Fatty acids in adipocytes, and lipoprotein lipase converts free floating TG into fatty acids , both for use in the muscles and cells as energy
WHat are the 3 components most strategies use to manage obesity
diet control
physical activity
behaviour (slow eating)
what are the general principles behind energy restricted diets
intake should be lower than output
adequate nutrient intake and physical activity should be ensured
should all be combined with lifestyle changes
WHat are some diet categories
-moderate calorie deficient (1200-1500)
-low calorie diet (1000-1100)
very low calorie diet (800) - only when BMI is above 32
the greater the caloric restriction, the greater risk of micronutrient deficiencies
What are some issues with FAD diets
unbalanced macronutrients
exclusion of major food group
micronutrient deficiencies
replacement of foods with supplements
lack of emphasis on physical activity
What are 4 complex interactions that can offset energy balance and promote obesity
psychology (social/individual)
food (production/consumption)
Physical activity (environment and individual)
Physiology
How does childhood obesity treatment differ to adult obesity treatment
low physical activity problem
involves controlled weight gain, not loss
formula for estimated weight gain per year is:
estimated weight gain = [(est adult weight +/- 10%) - current child weight] / years to adulthood
What are the 3 types of coronary heart disease
Atherosclerosis
thrombosis
inflammation
WHat is atherosclerosis
buildup of plaque in blood vessel
promoted by factors that increase serum cholesterol (LDL to HDL ratio), TG concentration, and chronic inflammation
What are some factors that can have an impact on CHD risk
smoking
low physical activity
diabetes and visceral obesity
age/gender
family history
hypertension
stress
WHat are the dietary fatty acids
Saturated (no double bonds) (raises CHD risk by promoting LDL) - butter, cheese, meats
unsaturated (double bond) (good for you, found in olive/canola oil and butter)
Essential fatty acids (omega-6 - linoleic, proinflammatory, found in sunflower, peanuts, corn) (Omega-3 - alpha-linolenic, anti-inflammatory, found in canola oils and fish)
Trans-fatty acids (meats/dairy and chemical partial hydrogenation (heating)) - have double bond with no kink (non-cis)
What are prostaglandins, prostacyclins, and thromboxanes
autocrine/paracrine signalling lipids derived from fatty acids
What are dietary oils
most abundant fatty acid, olive oil is monounsaturated with the main component being oleic acid
WHat are chylomicrons
made in enterocytes, enter blood via lymph and assist with lipid delivery (High TG)
What are VLDL
very low density lipoprotein
produced by liver
lipid delivery to tissues (high in TG)
WHat is LDL
Low density lipoprotein
produced through metabolism of VLDL
major source of exogenous cholesterol tissues
what is HDL
High density lipoprotein
produced by liver
anti-atherogenic, reverses cholesterol transport
good for health
How do you calculate the total change in cholesterol?
total change (mg/dl) = 2.1 (change in SFA intake) + 0.07 (change in dietary intake in mg/day) - 1.2 (change in dietary intake in percentage)
WHat are some antioxidant vitamins
vitamin E
what are some anti-homocysteine b-vitamins
folate, B12, and B6
How much fiber intake is recommended
25-30g per day, lowers LDL by 10%
What do plant sterols do
lower cholesterol and bile absorption in GI tract
What are the dietary guidelines for CVD prevention
Lowering plasma cholesterol
less saturated and trans fat foods
lower energy intake for weight loss
more fiber, fruits, and veggies
more omega 3
What are some factors involved with hypertension
body fat/weight (most important)
salt intake
alcohol intake
physical inactivity
genetics
old age
metabolic syndrome
What is the Dash Diet
Dietary Approaches to Stop Hypertension
emphasizes plant foods and restricts processed meats and foods high in salt and saturated fat
WHat is nutrition in adulthood primarily aimed at
preventing age related disease development
what are some nutrition related challenges that may be more relevant to adulthood
lack of time for food prep/planning leading to more processed and fast foods
What are some general nutritional recommendations for adults
increase intake of fruits/veggies due to high phytochemicals and nutrient density
consume less saturated fats and more omega 3 fats
replace simple sugars with complex carbs
take supplements to avoid deficiencies (should not replace servings of fruits and should not lower motivation to make other changes)
What are nutraceuticals
dietary supplements where the active compound is taken at high doses for pharmacological effects
WHat are probiotics
beneficial live bacteria consumed with fermented foods (yogurt) or taken as pill form
What are prebiotics
food components (fiber/phytochemicals) that promote beneficial bacteria growth in the gut by creating a healthy microbiota
What is the function of the human microbiome
to metabolize dietary components like fiber
What are some functions of fiber
increased rate of transit thru colon
prevention of constipation
prebiotic effect
decreased LDL
decreased glucose absorption rate
increased satiety
What are some examples of soluble fiber
pectins
psyllium
inulin
what are some examples of insoluble fiber
cellulose
chitin
lignins
what are xenobiotics
compounds not made by the body, they are modified by cytochrome P450 (CYP) and metabolized to eliminate xenobiotics from the body. Phytochemicals (like naringenin - lowers, or hyperforin - increases) can affect CYP activity and can affect elimination of xenobiotics
What are antinutrients
substances that interfere with nutrient absorption
exampkes include
- phytic acid (from seeds/grain, interferes with absorption of positively charged minerals)
Oxalic acid (tea, spinnich, interferes with calcium absorption)
amylase inhibitors (kidney beans, interfere with starch digestion)
protease inhibitors (soy, interferes with protein digestion)
Lectins (plant foods, interferes with nutrients)
What are phytochemicals
found in plants, have antioxidant properties but are not efficiently absorbed in the gut.
what are flavonoids
large group of phytochemicals that have potent antioxidant activities, and can reduce the risk of cancer and CVD
WHat are carotenoids
antioxidant phytochemicals that reduce risk of disease (like beta-carotene in fruits)
what are phytoestrogens
hormone related effects and lowers risk of cancer and disease, found in pumpkin and flax
what benefits does Garlic have
active compound - thiols
alliin -> allicin
anticoagulant and antibacterial
WHat benefits does tea have
Camella sinesis
green - unoxidized
black - oxidized
rich in flavonoids and catechins
lowers risk of CVD
What does Vaccinium do
Berries (like blue berries)
rich in anthocyanin flavonoids
higher bioactivity
What benefits does soy have
lowers risk of chronic diseases
high quality protein source
source of isoflaones
however can be allergenic and can contain substances that lower absorption of micronutrients
How much weight should mothers gain during pregnancy
12-16kg, lower weight gain recommended with higher BMI women
What are the most common deficiencies associated with pregnancy
iron, calcium, and folate
recommended higher intakes of magnesium, calcium, and phosphorus
What are some general recommendations regarding nutrition during pregnancy
sufficient macro/micro nutrients
avoid all alcohol and high caffeine
normal sodium intake for fluid balance
increase energy intake by 15-20% for energy
50% higher protein intake for tissue synthesis
50% higher vitamin B6 intake for protein synthesis support
30% higher vitamin B3, B1, and B2 intake for metabolic purposes
50% higher vitamin B9 intake (DNA synthesis support)
50% higher Iron intake for more red blood cell production
40% higher zinc intake for metabolic reactions and developmental defect reduction
50% higher iodine for prevention of mental retardation
10-15% more magnesium to lower risk of pre-eclampsia
WHat do deficiencies of folate lead to in pregnancy
severe - megaloblastic anemia (large blood cells due to blocked DNA synthesis)
Mild - premature/low birth weight risk, as well as neural tube defects
How much vitamin A is needed for pregnant women
same as normal, excess retinoids can cause higher risk of developmental abnormalities
What is pre-eclamsia
high BP
high urinary protein
edema
low uterine blood flow
loss of placental size
occurs in 5% of pregnancies, often in the 3rd trimester
associated with low vitamin D and magnesium, obesity, hypertension, and diabetes
what is eclampsia
progression of pre-eclampsia
seizures
dizziness
disturbed eyesight
can be fatal
often requires immediate c-section
WHat are 3 other issues with pregnancy
nausea/vomiting (very common, recommended to eat smaller meals and more snacks)
constipation and hemorrhoids (increased fluid and fibre-rich foods)
gastric reflux (heartburn) -recommended to slow eating process and avoid large fluid volumes
What are some foods you should eat during pregnancy
milk and other high protein foods
fish for omega 3 fats (low in mercury)
increased veggies
increased high nutrient density foods
minimize exposure to pesticides from non-organic plants (apples,strawberries, grapes, celery, peaches, spinich, bell peppers, nectarines, cucumbers, tomatoes, snap peas, and potatoes)
minimize mercury exposure (ocean fish)
minimize BPA
WHat are the benefits for lactation
nutritionally balanced
anti infection factors
non allergenic
can lower risk of diseases and cancers
what is the compensation of lactated milk
depends on mothers diet, contains trans fat along with vitamins and minerals,cholesterol and calcium not affected by diet
WHat are the dietary recommendations for a lactating mother
increase calories by 300-400 per day
increase protein by 50%
increase zinc by 50%, iodine by 90%
decrease iron by 50%
increase vitamin A by 90%
increase vitamin C by 80%
increase essential fatty acid intake
WHat are the diet recommendations for infancy/childhood
sufficient energy intake is critical to maintain normal growth
higher protein recommendations
iron / amino acid deficiency is common
cow milk not recommended til age of 1 due to immature kidney function
require more water per kg
iron fortified cereal is usually the first food
fruit juices not recommended before 6 months due to high sugar
iodine deficiency is a global issue with low marine food consumption and iodized table salt
what are the dietary recommendations for adolescence
more concerns involving eating disorders
sufficient energy and high quality protein for body growth
reduce sugar (common problem of excessive added sugar and fats)
conditions of overweight and obesity is a growing issue, relates to lack of activity and excessive energy intake
calcium recommendations are highest in teens alongside vitamin D for calcium absorption and bone health
