Nutrition Exam 1

nutrition

the science of foods and the nutrients and substances they contain and their action, interaction, and balance in relation to health and disease

nutrients

substances essential for health, that the body cannot make or makes in quantities too small to support life and that are essential for growth and maintenance of proper body function

essential nutrients

your body cannot make them or make enough of them, so you have to eat them

6 nutrients

carbs, protein, lipids/fats, vitamins, minerals, water

3 basic functions of nutrients

1. provide energy

2. promote growth and development

   1. regulate metabolism

energy yielding nutrients

carbs, lipids, proteins

energy yielding carbs

glucose (bagel, pasta, candy, fruit)

energy yielding lipids (fats/oils)

linoleic acid (omega 6) and alpha-lineoic acid (omega 6)

energy yielding proteins

amino acids (lysine, methionine, phenylalanine, threonine)

nonenergy yielding nutrients

vitamins (water-soluble), vitamins (fat-soluble), minerals (major), minerals (minor), minerals (questionable)

3 functional categories of nutrients

1. provide energy

2. promote growth and development

3. regulate body processes

nutrients that provide energy

carbs, proteins, lipids

nutrients that promote growth and development

proteins, lipids, some vitamins, some minerals, water

nutrients that regulate body processes

proteins, some lipids, some vitamins, some minerals, water

macronutrients

body requires them in large amounts

specific macronutrients

carbs, proteins, fats, water

micronutrients

required in small amounts

specific micronutrients

vitamins and minerals

carbs yield

4 calories/gram

lipids yield

9 calories/gram

proteins yield

4 calories/gram

alcohol yields

7 calories/gram

phytochemicals

physiologically active compounds found in plants that may provide health benefits

zoochemicals

physiologically active compounds found in foods of animal origin that may provide health benefits

phytochemical examples

stilbenoids (reservatrol) and flavanoids

stilbenoids (reservatrol) found in

blueberries, grapes, peanuts, red wine

zoochemical examples

sphingolipids and conjugated linoleic acid

sphingolipids and conjugated linoleic acid found in

meat, dairy products, cheese

functional foods

foods rich in phyto and zoo chemicals; provide health benefits beyond those supplied by the traditional nutrients it contains

conventional foods

unmodified whole foods

examples of conventional foods

fruits, veggies, herbs, spices, nuts, dairy, and fish

modified foods

fortified, enriched, and enhanced

examples of fortified foods

calcium fortified OJ, omega-3 enriched bread

medical foods

used under medical supervision to manage health conditions

special dietary use foods

help meet dietary needs (lactose free, sugar free, gluten free)

food choice factors

• social needs

• social network of family and friends

• food customs/culture

• food cost

• education

• occupation

• income

• routine and habits

• beliefs

• food marketing and influences

• food availability

• food flavor, taste, and appearance

• psychological needs

hunger

the physical need for food

appetite

the psychological desire to eat

desirable (optimal) nutritional status

the body has enough to support normal functions and build surplus stores

malnutrition

undernutrition and overnutrition that are subclinical

subclinical

early stage of nutrient deficiency where no overt signs/symptoms are seen

undernutrition

nutrient intake does not meet needs and nutrient store is depleted

overnutrition

consumption of more nutrients than the body needs (excess energy/calorie intake)

6 of 10 leading causes of death that are impacted by nutrition

1. cancer

2. heart disease

3. cerebrovascular disease (stroke)

4. diabetes

5. alzheimer disease

6. kidney disease

healthy people 2030

report that provide science-based goals for improving the health of all Americans every 10 years - attain healthy, thriving lives and well-being, free of preventable disease, disability, injury, and premature death

types of research

epidemiological and experimental

epidemiological studies

determine incidence (# of cases) and distribution (who, when, where) of diseases in a large population; observational studies (no cause and effect)

experimental studies

explore effects of specific variable on a tissue, cell, molecule; cause/effect (dependent/independent variables); uses RCT (randomized controlled trials)

common qualities of healthy diets

variety, balance, adequacy, and moderation

variety

choosing different foods

balance

the right proportions of foods from each group; appropriate amount of calories, macro/micros, and not too much

adequacy

getting enough essential nutrients for healthy people; sufficient energy (calories)

moderation

regularly selects food low in solid fat and added sugars; not over-indulging

dietary reference intakes (DRIs)

• recommendations from the food and nutrition board

• apply to people in the US and canada

• apply to health people

• gender and age specific

• used to assess the nutritional adequacy of individuals and populations

• should be applied to dietary intake averages over a number of days, not a single day

5 sets of standards of dietary reference intakes (DRIs)

1. estimated average requirements (EAR)

2. recommended dietary allowance (RDA)

3. adequate intakes (AI)

4. tolerable upper intake levels (UL)

5. estimated energy requirements (EER) and acceptable macronutrient distribution range (AMDR)

estimated average requirments (EAR)

• average amount sufficient for half the population

• closest to everyone’s needs (but half would develop deficiencies if only consume average)

• develop/evaluate nutrition programs for groups, not individuals (school children, military personnel, etc)

recommended dietary allowances (RDA)

• EAR is needed to set RDA

• is higher than the average human needs

• set at an amount based on the nutrients ability to prevent chronic disease rather than just prevent deficiency

• recommendations to meet needs of most healthy people in a life stage (98%)

• if intake regularly drops below the RDA, especially below the EAR, the risk of developing a deficiency is greater

adequate intakes

• value is set instead of an RDA

• insufficient scientific evidence for certain nutrients to establish EAR

• should cover the needs of 97-98% of individuals

• expected to exceed average requirements

• set goals for individuals

tolerable upper intake levels (UL)

• max daily amount safe for most healthy people

• above this point the nutrient intake is likely to be toxic

• not a nutrient goal, but a ceiling below which nutrient intake should remain

estimated energy requirements (EER)

• average daily energy (calorie) intake to maintain energy balance in a person through life stage

• no upper levels - any amounts in excess of energy needs results in weight gain

acceptable macronutrient distribution ranges (AMDR)

• determines nutrient composition of diet expressed as % of calories

• set for intake of carbs, protein, fat, essential fatty acid

• reduces risk of chronic disease and promotes good health

AMDR for carbs

45-65% kcal from carbs

AMDR for fat

20-35% of kcal from fat

AMDR for protein

10-35% kcal from protein

nutrient-dense foods

provide healthy nutrients in appreciable amounts relative to calories (most nutrients for the fewest calories)

energy dense foods/empty calorie foods

provide calories and low amounts of nutrients

examples of energy dense foods

fats, sugars, an alcohol (soda, chips, cookies)

Food labels

• overseen by FDA

• nutrition labeling and education act (NLEA) required standardized food labeling

nutrition label must have

• total calories

• total fat, sat fat, trans fat in grams and %DV

• cholesterol in mg and %DV

• sodium in mg and %DV

• total carbs in g and %DV

• fiber in g and %DV

• total sugar (grams only)

• added sugar in g and %DV

• protein (grams only)

• iron in mg and %DV

• vitamin D in mcg and %DV

• potassium in mcg and %DV

• calcium in mg and %DV

daily values

generic standards developed by the FDA; compare the amount of nutrients in the food with a set of standards (recommended daily amounts)

daily reference value for calories from fat

35%

daily reference value for calories from sat. fat

10%

daily reference value for calories from carbs

60%

daily reference value for calories from protein

10%

nutrient content claim

describes the level of a nutrient or dietay substance in a product using terms susch as “good source",” high, or “reduced”

“good” source

10-19% of the DV per serving

“high/excellent” source

>20% of the DV per serving

“low” source

5% of less of DV

health claim

describes the link between a food, food component, or dietary supplement substance and reduced risk of a disease; MUST BE APPROVED BY THE FDA

structure/function claim

describes the role of a nutrient or a dietary substance in maintaining health; NOT reviewed or authorizes by the FDA; must NOT mention a disease or symptom

dietary guidlines for americans

developed by the USDA (some input from DHHS); reflect the most accurate and up to date scientific knowledge about nutritious diets, physical activities, related healthy lifestyle choices

major nutrients in grains

carbs, fiber, iron

major nutrients in veggies

carbs, fiber, vitamins, minerals

major nutrients in fruit

carbs, fiber, vitamins, minerals

major nutrients in dairy

carbs, protein, calcium

major nutrients in protein

protein, iron

anatomy of the digestive tract

mouth, salivary glands, esophagus, stomach, pancreas, liver, gallbladder, small intestine, large intestine

stomach holds __ cups

4

small intestine is ___ feet long

10

large intestine is __ feet long

3.5

digestive system

digests food, absorbs nutrients, and excretes waste;

is controlled by hormones and the nervous system;

houses bacteria;

regulation of food intake depends on neurotransmitters and hormones (Ghrelin)

microbiota

bacteria in large intestine; part of the microbiome

accessory organs of the digestive system

salivary glands, liver, pancreas, gallbladder

functions of mouth/salivary gland

prepares food for swallowing (chewing, moistening with saliva) by turning it into a food bolus;

detects taste molecules

start digestion of starch with amylase enzyme

where does digestion start

in the mouth with the digestion of starch with amylase enzyme

function of esophagus

moves food to stomach by peristaltic waves initiated by swallowing

function of stomach

secretes gastric juices containing acid, enzymes, and hormones;

mixes food with gastric juice, converting it to liquid chyme;

starts digestion of protein;

slowly releases chyme into small intestine

function of small intestine

mixes chyme with bile and pancreatic juice to complete digestion;

secretes hormones that help regulate digestive processes;

secretes digestive enzymes;

absorbs nutrients and other compounds in foods;

transports remaining residue to large intestine

large intestine

absorbs water and electrolytes (sodium and potassium);

forms and stores feces;

houses most of gut bacteria

function of liver

produces bile to aid fat digestion and absorption;

secretes bile to digest fats