Vocab Flashcards
(79 cards)
micronutrients macronutrients
Nutrient needed in milligram or microgram quantities in a diet. Vitamins and minerals are micronutrients.
Nutrient needed in gram quantities in the diet. Fat, protein, and carbohydrates are macronutrients.
Because carbohydrates, proteins, lipids, and water are needed in large amounts,they are called macronutrients. In contrast, vitamins and minerals are needed in such small amounts in the diet that they are called micronutrients. Let’s now look more closely at the classes of nutrients.
Enzyme
enzyme Compound that speeds therate of a chemical process but is not altered by the process. Almost all
enzymes are proteins.
Photochemicals
Phytochemicals (plant components in fruits, vegetables, legumes, and whole grains) and zoochemicals (components in animals) are physiologically active compounds. They are not considered essential nutrients in the diet. Still, many of these substances provide sig-nifi cant health benefi ts
DRIs
The latest recommendations from the Food and Nutrition Board are called Dietary Reference Intakes (DRIs). 2 The DRIs apply to people in both the United States and Canada because scientists from both countries worked together to establish them. The DRIs include 5 sets of standards: Estimated Average Requirements (EARs), Recommended Dietary Al-lowances (RDAs), Adequate Intakes (AIs), Tolerable Upper Intake Levels (Upper Levels, or ULs), and Estimated Energy Requirements (EERs) (see the inside covers of this textbook). 1DRIs are set for almost 40 nutrients. Although not a DRI, Adequate Macronutrient Distri-bution Ranges (AMDRs) were established for guidance on intake levels of carbohydrates, protein, and fat to help reduce the risk of nutrition-related chronic diseases. 3 - 5
The DRIs are composed of Estimated Average
Requirements (EARs), Recommended Dietary
Allowances (RDAs), Adequate Intakes (AIs),
Tolerable Upper Intake Levels (Upper Levels, or
ULs), and Estimated Energy Requirements (EERs).
RDAs
Recommended Dietary Allowances (RDAs) are daily nutrient intake amounts sufficient to meet the needs of nearly all individuals (97 to 98%) in a life stage (see the inside covers). RDAs are based on a multiple of the EARs (generally, the RDA = EAR × 1.2). Becauseof this relationship, an RDA can be set only for nutrients that have an EAR. (Recall that a measurable functional marker is required to set an EAR.) An additional consideration made when setting an RDA is the nutrient’s ability to prevent chronic disease rather thanjust prevent deficiency
DVs
The Nutrition Facts panel on a food label compares the amount of nutrients in the food with a set of standards called Daily Values (DVs). DVs are generic standards that were developed by the U.S. Food and Drug Administration (FDA) because the DRIs are age- and gender-specific and it isn’t practical to have different food labels for men and women or for teens and adults.
Daily Value (DV): Generic nutrient
standard used on Nutrition Facts labels;
it comprises both Reference Daily Intakes (RDIs) and Daily Reference Values (DRVs).
DRVs
reference Daily Intakes (rDIs): Part of
the DV; generic nutrient standard set for
vitamins and minerals (except sodium andpotassium).
Daily Reference Values (DRVs) are standards for energy-producing nutrients
(fat, saturated fat, carbohydrate, protein, fi ber), cholesterol, sodium, and potas-
sium. Many of these nutrients do not have an established RDA or other nutrient
standard (e.g., total fat, saturated fat, carbohydrate).
The DRVs for the energy-producing nutrients are based on daily calo-
rie intake. The FDA selected 2000 calories as the reference for calculating
percent DVs for energy-producing nutrients, although larger food packages
can display values for both a 2000- and a 2500-calorie diet. Regardless of the
calorie level used, the DRVs for energy-producing nutrients are always calcu-
lated like this:
• Fat is set at 30% of calories.
• Saturated fat is set at 10% of calories.
• Carbohydrate is set at 60% of calories.
• Protein is set at 10% of calories.
• Fiber is set at 11.5 g of fi ber per 1000 calories.
Note that the values for sodium, potassium, and cholesterol, as well as the vitamins andminerals that have RDIs, do not vary with calorie intake.
RDIs
Reference Daily Intakes (RDIs) are set for vitamins and most minerals—these nu-trients all have established nutrient standards, such as RDAs. RDI values for people over age 4 years tend to be set at the highest value for any life-stage group in the 1968 edition of the RDAs. Consider iron—in 1968, adult women and adolescents had the highest iron RDA (i.e., 18 mg/day). The iron RDI for people over age 4 years was set at this value. The RDI values currently in use are generally slightly higher than current RDAs and related nutrient standards (see Table 2-2 ). Many nutrition experts believe the RDIs should be revised to refl ect the latest nutrientstandards
AIs
adequate Intake (aI) Nutrient intake amount set for any nutrient for which insufficient research is available to establish an RDA. AIs are based on estimates of intakes that appear to maintain a defined nutritional state in aspecific life stage.
Adequate Intakes (AIs) Adequate Intakes (AIs) are daily intake amounts set for nutrients for which there are in-suffi cient research data to establish an EAR (see the inside covers). AIs are based on ob-served or experimentally determined estimates of the average nutrient intake that appears to maintain a defi ned nutritional state (e.g., bone health) in a specifi c life-stage group. 1 In determining the AI for a nutrient, it is expected that the amount exceeds the RDA for that nutrient, if an RDA were known. Thus, the AI should cover the needs of more than 97 to 98% of the individuals in a specifi c life-stage group. The actual degree to which the AI exceeds the RDA likely differs among the various nutrients and life-stage groups. Like the RDA, the AI can be used as the goal for usual intake of that nutrient by an individual. Cur-rently, essential fatty acids, fi ber, and 9 vitamins and minerals, including some B-vitamins, rently, essential fatty acids, fi ber, and 9 vitamins and minerals, including some B-vitamins, vitamin D, the vitamin-like compound choline, calcium, and fl uoride, have AIs. vitamin D, the vitamin-like compound choline, calcium, and fl uoride, have AIs.
ULs
Tolerable Upper Intake Levels (Upper Levels, or ULs) Tolerable Upper Intake Levels (Upper Levels, or ULs)
Tolerable Upper Intake Levels, or Upper Levels (ULs), are the maximum daily intake Tolerable Upper Intake Levels, or Upper Levels (ULs), are the maximum daily intake amounts of nutrients that are not likely to cause adverse health effects in almost all indi-amounts of nutrients that are not likely to cause adverse health effects in almost all indi-viduals (97 to 98%) in a life-stage group (see the inside covers).viduals (97 to 98%) in a life-stage group (see the inside covers). 1 The amount applies to chronic daily use and is set to protect even those who are very susceptible in the healthy chronic daily use and is set to protect even those who are very susceptible in the healthygeneral population. For example, the UL for vitamin C is 2000 mg/day. Intakes greater general population. For example, the UL for vitamin C is 2000 mg/day. Intakes greater than this amount can cause diarrhea and infl ammation of the stomach lining.
Health Claims
Health claims describe a relationship between a disease and a nutrient, food, or food constituent. 12 All permitted health claims have signifi cant scientifi c agreement that they are true. All health claims must use a may or might qualifi er in the statement. Thefollowing are permitted health claims.
• A diet with enough calcium may reduce risk of osteoporosis.
• A diet low in total fat may reduce risk of some cancers.
• A diet low in saturated fat and cholesterol may reduce risk of cardiovascular disease (typically referred to as heart disease on the label).
• A diet low in saturated fat and cholesterol that also includes 25 g/day of soy pro-tein may reduce risk of cardiovascular disease. The statement “one serving of (food name) provides ______ g of soy protein” must also appear as part of the health claim.
• Fatty acids from oils present in fi sh may reduce risk of cardiovascular disease.
Structure/function claims
Structure/function claims describe how a nutrient affects hu-man body structure or function, such as “iron builds strong blood.” They do not focus on disease risk reduction, as health claims do. The FDA does not approve or authorize structure/function claims; however, manufacturers are responsible for ensuring that these claims are accurate and not misleading.
Organic
The term organic refers to the way agricultural products are produced. Organic production relies on farming practices such as biological pest management , com-posting, manure applications, and crop rotation to maintain healthy soil, water, crops,and animals
Neurotransmitter
Many neurotransmitters, released by nerve endings, also are derivatives of amino acids. This is true for dopamine (synthesized from the amino acid tyrosine), norepinephrine (synthesized from the amino acid tyrosine), and serotonin(synthesized from the amino acid tryptophan).
Hormone
Amino acids are required for the synthesis of most hormones in the body. Some hor-mones, such as the thyroid hormones, are made from only 1 amino acid, whereas oth-ers, such as insulin, are composed of many amino acids. Hormones act as messengers in the body and aid in regulatory functions, such as controlling the metabolic rate and theamount of glucose taken up from the bloodstream
Digestive enzymes; identify each, where they are secreted, and what they act upon
Digestive enzymes are pro-tein molecules that speed up digestion by catalyzing chemical reactions. Catalysis brings certain molecules close together and then creates a favorable environment for the chemi-cal reaction. (Appendix B provides details on enzyme action.) Digestive enzymes catalyze chemical reactions known as hydrolysis reactions . In these reactions, water ( hydro- ) breaks apart ( -lysis ) molecules that are too large to pass though the GI tract wall. Hydrolysis reac-tions eventually yield simple molecules that are small enough to be absorbed through theintestinal wall.
Irradiation
Food irradiation, sometimes known as cold or electronic pasteurization, is one of the new-est food preservation methods. It uses radiant energy from gamma rays, X rays, or electron beams to extend the shelf life of food and to control the growth of insects and pathogens (bacteria, fungi, parasites) in foods. 41 Foods are exposed to controlled doses of radiant en-ergy, which essentially pass through the food. Just as an airport scanner or dental X rays do not make your luggage or teeth radioactive, irradiated food is not radioactive. The historyof food irradiation goes back nearly a century and includes scientifi c research, evaluation, and testing. Irradiated foods are safe in the opinion of the FDA and many other health authorities, including the American Academy of Pediatrics
food-borne illness; list 6 examples and typical food sources
Salmonella species
Raw and undercooked meats,
poultry, eggs, and fi sh; produce,especially raw sprouts; peanut
butter; unpasteurized milk
Shigella species Fecal/oral transmission; water supplies, produce, and other foods contaminated by infected food handlers with poor hygiene
Hepatitis A virus Foods prepared by infected food handlers, especially uncooked foods or those handled after cooking, such as sandwiches, pastries, and salads; shellfi sh from contaminated waters;vegetables and fruits contaminated during growing, harvesting, and processing
Norovirus (Norwalk and Norwalk-like viruses), humanrotavirus Foods prepared by infected food handlers; shellfi sh from contaminated waters; vegetables and fruits contaminated duringgrowing, harvesting, and processing
Trichinella spiralis
Pork, wild game
Tapeworms
Raw beef, pork, and fish
GRAS List
Prior-Sanctioned Substances and the GRAS List The 1958 Food Additives
Amendment exempted 2 groups of substances from the food additive regulation
process. All substances that the FDA or USDA determined were safe for use
in specifi c foods prior to this amendment were designated prior-sanctioned
substances. Examples of prior-sanctioned substances are sodium nitrite and
potassium nitrite, used to preserve luncheon meats. A second category of
substances excluded from the food additive regulation process are substances
Generally Recognized As Safe (GRAS) by experts, based on the substances’
extensive history of use in food before 1958 or by published scientifi c evidence. Salt, sugar, spices, vitamins, and monosodium glutamate are classifi ed as GRAS substances,along with several hundred other substances
Since 1958, some substances on the GRAS list have been reviewed and some have been deleted from the list and the food supply. One example is safrole, a natural fl avor-ing once used in root beer. Many certifi ed color additives have been removed because of evidence of cancer and organ damage. Most chemicals on the GRAS list have not been reviewed (e.g., vanilla, salt, vinegar), primarily because of expense and their long histories of use coupled with lack of evidence for toxicity
Food additives; list 6 examples
Today, the FDA regulates over 3000 food additives. Food additives are substances added to foods to produce a desired effect, such as a longer shelf life (preservative), greater nutritional value, or a more appealing color. As the demand for convenient, time-saving prepared foods has increased, so have the need for and use of food additives. Many foods are prepared at large, central processing plants, transported long distances, and then held in warehouses for some time before purchase. Food additives can help keep foods appetizing, fresh, nutritious, and safe. Consider a typical lunch menu of a ham-burger, cucumber salad with dressing, and lemonade. The hamburger bun is enriched with nutrient additives and contains a preservative to keep it fresh. The cucumber skinmay be waxed to extend its shelf life and may contain an infi nitesimal amount of pesticide residue, which technically is an additive. The dressing contains an emulsifi er additive to keep it from separating and a preservative to keep it from spoiling. The convenient lem-onade mix consists of additives (sweeteners, fl avors, and colors) dissolved in water.
Prebiotic
Prebiotics are non-digestible carbohydrates that promote the growth of benefi cial bacteria in the large intestine. 12 One example is inulin , a carbohydrate made of several units of fructose (a sugar). Inulin is found in many foods, including chicory, wheat, onions, garlic, asparagus, and bananas. Inulin and other related compounds, such as fructans, a r e
added to some processed foods to add texture, bulk, and potential health benefi ts. Another prebiotic is resistant starch, found in whole grains and some fruits. resistant starch resists the action of digestive enzymes in the small intestine; thus, bacteria in the large intestine can ferment it. Prebiotics fermented in the large intestine produce short-chain fatty acids and other organic acids. In studies of prebiotics, participants typically ingest 10 to 20 gramsper day; such large amounts can cause fl atulence, bloating, and other GI distress. As with probiotics, the research that prebiotics improve health is not yet conclusive.
Probiotic
Probiotics are live microorganisms that provide health benefits when they are consumed in sufficient amounts. 10 Probiotics are found in fermented foods, such as yogurt and miso (fermented soybean paste), and are sold in capsules and powders. Probiotic bacteria usually are Lactobacilli or Bifi dobacteria.
Probiotic bacteria are thought to colonize in the large intestine and provide certain health benefi ts. For instance, probiotics may help prevent and treat diarrhea, prevent food allergies and colon cancer, and treat irritable bowel syndrome and infl ammatory bowel dis-ease. 11 However, this research is not conclusive. Probiotics are diffi cult to study because of the many types and doses of microorganisms available to test. Most studies have had relatively few participants and short treatment durations. Currently, the best evidence is that probiotics can help prevent and treat diarrhea in children. Probiotics also can help treat antibiotic-associated diarrhea and prevent the travelers’ diarrhea that affl icts many individuals traveling to less de-veloped nations.
Celiac disease
A recent National Institutes of Health panel has drawn attentionto celiac disease, an immune-mediated disorder that affects
primarily the gastrointestinal tract. Celiac disease, sometimes
known as gluten intolerance, is caused by a physiological
response to a protein called gluten, found in wheat and related
grains, such as rye, barley, spelt, and triticale. In persons with
celiac disease, these proteins damage the villi of the small
intestine, causing the villi to flatten. In many persons with
celiac disease, damage to the villi results in the malabsorption
of nutrients. Currently, health experts believe that celiac disease
results from both genetic and immunological factors.
Monosaccharide; list 3 examples
Class of single sugars that are not broken down further during digestion.
Glucose, fructose, and galactose
