Basis of a healthy diet Flashcards
Healthy diet
results in absence of illness, discomfort -> brings fitness, longevity and optimum health
Key variables influencing nutritional demands and disease prevalence
stage of development, level of inflammatory stress, previous nutritional exposure in utero (fetal origins of adult disease), genetics
USDA recommendations
in the 70s it was high protein/high fat, in the 80s it became high carbohydrate/low fat/lean protein with a significant emphasis on weight loss, 2005 guidelines based on increasing rate of obesity
2010 advisory committee
advises Americans to eat nutrient dense (not energy dense) foods-> Americans not consuming enough healthy foods recommended
A daily multivitamin/mineral supplement
does not offer health benefits to healthy Americans
Older individuals
this population should consume fortified foods rich in vitamin B12 or B12 supplements if needs cannot be met through whole foods
US diet
too much solid fats, sugars, sodium, refined grains, not enough vitamin D, calcium, potassium, fiber, vegetables, fruits, whole grains, fluid milk, milk products and oils
2005 recommendations from the FDA
provide science based evidence to promote health and reduce risk of major chronic diseases -> eat fewer calories, be more physically active, eat healthy diet by making wiser food choices, prepare and handle foods to reduce risk of foodborne illness
Childhood obesity
significantly increased risk due to energy density of diet in childhood
Pregnancy
suggested to supplement Iron and folic acid
USDA food guide
recommendations for macronutrients/micronutrients are based on 2000 kcal diet
Negative energy balance
intake < expenditure -> ok if you are trying to lose weight, bad if you are recovering from infection/injury/malnutrition
Positive energy balance
intake > expenditure -> ok if you are trying to grow or recover for injury, infection or malnutrition
Physical activity
helps reduce risk of chronic diseases (type II diabetes) -> 3 components are cardio, stretching/flexibility, resistance exercises -> can also prolong life
Adult exercise requirements
should have 30 min moderate of moderate activity to reduce risk of chronic disease, 60 min of moderate to vigorous exercise to manage body weight and prevent weight gain, 60-90 min of moderate activity to sustain weight loss
Children exercise requirements
60 min of activity/day
Vegetables and fruits
recommend 4 and a half cups (9 servings) per day -> decreases risk
Vitamin E
antioxidant protects cell membrane from peroxidative damage -> alpha-tocopherol has best antioxidant property -> studies in cardiovascular disease gave mixed results
Beta Carotene
antioxidant protects against cancer in many studies with exceptions
Vitamin C
water soluble vitamin, no benefit against CVD in clinical trials
Antioxidant
selenium
Stomach cancer
decreased by high levels of daily fruit consumption
Non-starch polysaccharides (dietary fiber)
decreases risk of colon cancer -> bacteria convert it to butyric acid which benefits colon
Phytochemicals
compounds occurring in foods of plant origin -> implicated in protection against CVD, cancer and other disease -> genstein in soybeans have anti-tumorigenic properties, cruciferous veggies rich in Isothiocyanate, allylic sulfides, anthocyanines in grapes and berries
Vary your vegetables
dark green, orange, legumes, starchy, other
Carbohydrates
14 g of fiber/1000 calories -> choose fiber rich foods (NOT all fiber is the same), vegetables, and whole grains often -> don’t eat many foods with added sugars/caloric sweeteners
Sucrose
glucose and fructose
Lactose
glucose and galactose
Maltose
glucose + glucose
Polysaccharides
starch and inulin (not well digestible -> Jerusalem artichokes)
Fiber
fecal bulking, cholesterol lowering, fermentation by gut bugs gives butyric acid (important for gut epithelia health in lower bowel)
Whole grain
3 or more ounce equivalents -> half of your grain products -> contain more than just fiber (vitamins, minerals, antioxidants, carbohydrates, phytonutrients, minerals, fiber)
Starch and fibers
protect against heart disease and stroke and reduce risk of diabetes -> prevent colon cancer and promote weight management
Glycemic index
high = massive increase in glucose levels and massive increase of insulin (strain on beta cells of pancreas) -> no association with cancer and type II diabetes mellitus or cardiovascular disease (2010 recommendations get away from this)
Glycemic load
amount of carbohydrate multiplied by its glycemic index
Increased dietary fiber
higher stool weight and decreased transit time -> lowers risk of colon cancer (carcinogenic properties of some stuff in gut gets moved along)
Whole grains
decreases the incidence of coronary heart disease, type II diabetes, colon cancer and important in weight control
Food recommendations
4.5 cups of fruit and vegetables, low fat or fat free dairy products and eat half of your grains as whole grains (3 ounce equivalents/day)
Fat
energy dense -> palatable, increase sense of satiety, essential for absorption of certain vitamins -> animal vs. plant sources (animals and coconut oil richer in saturated, plants have unsaturated)
Omega 6 FA
found in corn and nut oils -> soft fats contain some of these
Fat for women
Breast cancer and endometrial cancer risk increases with increased intake (female sex hormones stored in adipose tissue)
Cholesterol levels
certain FA and obesity increases this (especially LDL) -> NOT all comes from fat (some made de novo from glucose) -> reduce saturated to < 7% of dietary energy -> less than 300mg/day for healthy subjects and less than 200mg (1 egg) for high risk (type II diabetes or CVD)
Short chain fatty acids
cholesterol raising -> lauric, myristic, palmitic
Healthful FA
monounsaturated (oleic -> anti-inflammatory, doesn’t influence cholesterol -> olive oil/canola oil); omega 6 polyunsaturated (linoleic acid -> rich in maize oil, sunflower oil, safflower oil); omega 3 polyunsaturated (EPA and DHA -> fish oils)
Total fat
should be 20-35% of daily calories, 2-3 years = 30-35, children and adolescents = 25-35 -> saturated less than 10%, cholesterol less than 300mg, trans fats as low as possible (significant increased risk of CHD)
Dairy
adults and children over 9 -> 3 cups per day of fat free or low-fat products -> if you can’t eat this make sure you get lots of calcium
Omega 3 FA
two servings/week during pregnancy and lactation will improve visual acuity of infant and improve cognitive function of infant
Sodium
consume less than 2300 mg (1tsp) per day -> foods with less than 140mg are low in this -> high BP consume less than 1500mg/day
Potassium
consume foods rich in this (fruits and vegetables) -> can help offset high sodium -> if high blood pressure make sure to get 4700mg/day
Decrease BP (blacks also benefit from this)
decrease sodium intake and increase potassium
Supplementation
no good evidence to suggest use in healthy individuals -> B12/B6 and folic acid can be useful in decreasing dementia
Selenium
no evidence of beneficial effect against CVD or cancer except if there is a deficiency
Homocysteine
if you are deficient of folic acid you will get a more significant decrease of this in your blood with folic acid supplements
Folic acid
protects against neural tube defects and may contribute to a fall in stroke mortality -> may have an increase in colorectal cancer (not as significant)
Vitamin A
in developing countries that may be deficient, giving this supplement showed significant decrease in mortality in children, also has benefit in birth weight by supplementing mothers
Alpha-tocopherol
lowers mortality from cancer, cardiovascular disease and overall total mortality
