midterm Flashcards
Def’s
(DRI) Dietary Reference Intake:
-values used for planning and assessing diets
(RDA) Recommended Daily Allowances:
-average daily amounts of nutrients considered adequate to meet the known needs of 99.9% of all healthy people.
-a goal for intake by individuals
-best used for INDIVIDUALS
(AI) Adequate Intake:
-used as a guide for nutrient intake when scientific evidence is insufficient for making an RDA
-best used for INDIVIDUALS
(UL) Tolerable Upper Levels:
-suggested upper limits of intakes of potentially toxic nutrients. Intakes above the UL are likely to cause illness from toxicity
(EAR) Estimated Average Requirements:
-Population-wide average nutrient requirement
-for research and policy-making
-better used to evaluate group nutritional needs
-RDA is based off EAR
-best used for GROUPS
(EER) Estimated Energy Requirement:
-the dietary energy intake level that is predicted to maintain energy balance in a healthy adult of a defined age, gender, and PA consistent with good health
(AMDR) Acceptable macro. Distribution Ranges:
-ranges of intakes for the energy-yielding nutrients that provide energy and nutrients and reduce the risk of chronic disease
AMDR macronutrient recommendations in percentages
carb 45-65%
protein 10-35%
lipid 20-35%
Six Classes of Nutrients
carb
protein
lipid
water
vitamin
mineral
Energy ProvidingNutrients
Carbohydrate = 4kcal/g
Protein = 4 kcal/g
Fat = 9 kcal/g
Alcohol = 7kcal/g
Kcalorie
Energy dense vs nutrient dense
Energy-dense:
-the energy food provides relative to the amount of food
-High-calorie count for the nutrients involved ex almond, avocado
Nutrient-dense:
-the nutrients food provides relative to the energy it provides ex fruit, veg, whole grains
-the more nutrients and the fewer kcalories, the higher the nutrient density
Types of health claims with examples
Def: a health claim is a relationship between a nutrient/substance in the food and a disease/condition
Ex:
Ca + reduced risk of osteoporosis
K + reduced risk of HTN and stroke
soy protein + reduced risk of heart disease
fruit,veg + reduced risk of cancer
dietary fat + reduced risk of cancer
sugar alcohols + reduced risk of tooth decay
Nutrient claim: describe the contents of a product
ex: free, zero, light, reduced
Nutrient facts: quantities and % of daily values
Structure-function claims: how a product may affect a structure/function of the body. These claims do not require FDA authorization
ex: Ca builds strong bones.
Tips for reading a food label
Ingredient list: in descending order of predominance by weight
Serving size: tip: need to be aware that serving size may differ from actual quantity eated!!
Daily % values: reference values made by the FDA for food labels. They set adequacy standards for desirable nutrients. Set moderation standards for nutrients that must be limited.
Alternate Names:
Sugar: dextrose, “-ose”, brown sugar, cane juice, corn syrup, fructose, honey, lactose, maltose, molasses,
Sodium: salt, baking power, baking soda, brine, garlic salt, onion salt, soy sauce,
Saturated fat: coconut or palm oil, bacon fat, lard, animal fats
Trans fat: hard margarine, hydrogenated fats and oils, shortening
Tips for evaluating health claims
-limitations of media to present important facts
-Findings are controversial, scientists may disagree
-Preliminary findings are used by the media and by commercial promotors
-Promotors know consumers like to try new products
-Was the study a properly designed scientific experiment? Can findings be replicated?
-Are findings based solely on personal testimonials?
-Are findings generalized for all people?
-Is the journal a respected journal? Has it been peer-reviewed?
Beware of:
*Quick and easy fixes
*Personal testimonials
*One product does it all
*Natural
*Time-tested or latest innovation
*Satisfaction guaranteed
*Paranoid accusations
*Meaningless medical jargon
*Too good to be true
Evaluating the reliability of websites:
-Consider who is responsible for the site
-Are names and credentials of information providers clearly identified? Is there a clear way to obtain more information?
-Is the site updated regularly?
-Is the site selling a product or service? Does the site charge a fee to gain access to it?
Primary determinants of healthy eating:
*Access to information
*Availability of healthy & acceptable foods
*Poverty
Social Learning Theory
Three sets of motivating factors:
(1)Physical motivators
(2)Social incentives
(3)Cognitive motivators
Transtheoretical model of Change
Precontemplation stage: an individual does not see a health problem, or does not have any intention of changing or modifying it in the foreseeable future
Contemplation stage: an individual has an awareness of a problem, and is considering making a change. The person remains ambivalent and lacks a strong commitment
Preparation stage: a person begins to take small steps towards changing difficult health-related habits. The individual is not fully committed to consistent action
Action stage: an individual has a strong commitment to change and is making consistent, definitive actions to make behavioural change
Maintenance stage: an individual stabilizes; gains achieved during the action stage are consolidated
Categorizing nutrients (ex: essential, energy-yielding, organic, micro/macro)
essential: nutrients the body can’t make and must be obtained from food
Energy-yielding: carb, protein, fat
Organic: contains carbon. the 4 organic nutrients are carbs, protein, fat, and vitamins
Inorganic: do not contain carbon or pertain to living things
Digestive processes (enzymes, organs, movements throughout the intestinal tract)
in notebook
Harmful effects of excessive fiber
Mineral imbalance: some minerals may bind to fiber and be excreted with it without becoming available for the body to use (when mineral intake is adequate, a reasonable amount of high-fiber foods doesn’t affect mineral balance tho)
Nutrient Displacement & Energy Requirements: people with marginal food intakes who eat mostly high-fiber foods may not be able to take in enough food to meet energy or nutrient needs
Increased fluid needs:
fibers carry water out of the body and can cause dehydration. Advise to drink water along with fiber. athletes to avoid bulky fiber-rich foods prior to competition
Chylomicrons, lipoproteins
Chylomicrons: the lipoproteins that transport lipids from the intestinal cells into the body. The cells of the body remove the lipids they need from the chylomicrons, leaving chylomicron remnants to be picked up by the liver cells
Lipoproteins: clusters of lipids associated with proteins that serve as transport vehicles for lipids in the lymph and blood
G’s!
Glucose: a monosaccharide; the sugar that makes up disaccharides. also called dextrose
Glycerol: three carbon compound that is the backbone of triglycerides and phospholipids
Glycogen: a polysaccharide composed of glucose, made and stored in the liver and muscle tissues as a storage form of glucose
Glucagon: a hormone secreted by special cells in the pancreas in response to low blood sugar concentration and elicits release of glucose from storage
Glycogenesis: process converting glycogen back to glucose
Gluconeogenesis: process producing glucose from fat and protein (not very efficient for fat)
release of glucose from glycogen: when blood sugar falls too low, glucagon is released into the bloodstream and triggers the breakdown of liver glycogen into single glucose molecules. Enzymes in liver cells respond to glucagon by attacking lots of branches of the glycogen molecule to release a surge of glucose into the blood. The highly branched structure of glycogen suits the purpose of releasing glucose on demand. Somatostatin is a hormone produced by the pancreas and hypothalamus that inhibits insulin and glucagon.
HDL vs LDL
HDL: high-density lipoprotein
-lipoproteins that help remove cholesterol from the bloodstream by transporting it to the liver for reuse or disposal
LDL: low-density lipoprotein
-lipoproteins that transport cholesterol in the blood
Types and functions of fiber;
DRI recommendations for fiber
Type of fiber in notebook
-help promote a healthy colon
-contain glucose but their bonds are not broken by enzymes = provide no energy
25-35g/day DRI
38 g/day for men
25 g/day for women
functions of fiber:
-diabetes reduction. soluble fibers like oats help regulate blood glucose following a carb-rich meal. Soluble fibers trap nutrients and delay their transit through the digestive tract, slowing glucose absorption and preventing the glucose surge and rebound associated with diabetes onset.
-gut health: bacteria in the colon ferment soluble fibers which allows them to flourish.
Coarse, insoluble fibers remain intact in the colon and stimulate the tissue lining to secrete water and mucus which enlarges and softens stool, easing their passage out of the body. Less pressure in the lower colon reduces risk of rectal vein swelling (causing hemorrhoids). Fiber prevents compaction which could obstruct the appendix and permit bacteria to invade and infect it.
-Cancer: increased fiber decreases colon cancer risk. all plant foods (fruit,veg,whole grains) dilute, bind, AND REMOVES POTENTIAL CANCER-CAUSING AGENTS FROM THE COLON.
Also, small fat-like molecules made from bacterial fermentation lower the pH, activate cancer-killing enzymes, and inhibit inflammation in the colon.
-weight management: fiber-rich foods are low in solid fats, added sugars and calories = prevent weight gain and promoting weight loss by delivering less energy per bite. Also, fibers absorb water from the digestive juices so their swelling creates feelings of fullness, delay hunger, and reduces food intake.
Fermentable soluble fibers form small fat-like molecules that shift hormones in ways that promote feeling of fullness.
