WVU HNF 171 Exam 1

Describe how various factors influence personal food choices

cost, availability, convenience and taste

six major classes of nutrients

Carbohydrates

Protein

Lipids (fats)

Vitamins

Minerals

Water

which classes of nutrients are E yielding

Carbs, Lipids, Proteins

which classes of nutrients are organic

carbs, lipids, proteins, vitamins

nutrition

the study of how food nourishes the body and influences health

carbohydrate

4 kcal/gram; mono (glu,fru); Di (suc); poly (starch); fiber (not digested by small intestine)

protein

4 kcal/gram; made of amino acids; 9 essential; 11 non-essential; hemoglobin in red blood cells delivers O2

lipid

9 kcal/g; triglyceride; phospholipid; sterol; unsaturated (liquid); saturated (solid)

alcohol

7 kcal/g; not a nutrient

vitamin

enable chem rxns; fat soluble (ADEK); Water soluble (CB)

mineral

used in cellular processes, nervous system, water balance and structure; trace

water

8 cups/day; humans are 60%; used as solvent, lubricant, transport, chemical processes and temp regulation

kcal

measure of energy needed to raise temp of 1kg H2O

fiber

carb; not digested in small intestine; often responsible for constipation

Scientific method

observation and question

hypothesis and prediction

experiment

results and interpretations

theory OR start over

What are DRIs and how are they used?

Dietary Reference Intake; set of nutrient intake values for healthy people in US and Canada

Recommendations for daily intake

Adequate Intake (AI) and Recommended Dietary Allowance (RDA)

UL

Upper Intake Level

Trusted experts

RD/RDN; Research from accredited universities; hospitals; well-known entities

ABCDEs of nutrition

Anthropometric

Biochemical

Clinical

Diet History

Environmental

RDA

Recommended Dietary Allowance; amt that meet 98% of pop; above EAR

EAR

Estimated Average Requirement; amt that meets 50% of population

EER

Estimated Energy Requirement; avg dietary energy intake to maintain energy balance

AMDR

Acceptable Macronutrient Distribution Range; adequate amt of nutrient proportional to energy to reduce risk of disease

What does dieting prevent and control?

Chronic Disease

Type 2 diabetes

benefits from dieting and weight loss

What's on a Nutrition label

Serving size, calories, daily values, added sugar, Vitamin D, Potassium

Does everything have to be on a label?

no, if less than 1g they don't have to include it

Steps of digestion

1. Digestion

2. Absorption

Mouth

chews and begins to chemically break up carbs with fluids from salivary glands

mechanical digestion

chewing

chemical digestion

enzymes and stomach acid break up

amylase

enzyme that breaks down starch/ carbs

bolus

A soft mass of chewed food.

epiglottis

A flap of tissue that seals off the windpipe and prevents food from entering.

upper esophageal sphincter

keeps food from coming up

lower esophageal sphincter

keeps stomach acid from coming up

what happens to the bolus in the stomach?

protein breaks down and muscles and gastric juice help this process

pepsin

An enzyme present in gastric juice breaks down proteins

gastric juice

contains HCl; unravels proteins

pyloric sphincter

Controls passage of food from stomach to small intestine

bolus after stomach

chyme

Parts of small intestine

duodenum, jejunum, ileum

function of small intestine

absorption of nutrients (vitamins and minerals also)

Gallbladder

stores bile

bile

A substance produced by the liver that breaks up fat particles/emulsifier.

pancreas

produces hormones (insulin and glucagon) and 3 enzymes; in loop of duodenum; produces bicarbonate ions to neutralize chyme

Liver

produces bile; synthesizes chemicals; releases glucose to maintain blood sugar

Large Intestine

fiber and starch not broken down go here; absorption of H2O and short chain fatty acids; bacteria help with final digestion

Microbes

nonharmful bacteria in the gut that ferment fibers

probiotics

good bacteria

prebiotics

food/fiber for probiotics

microbes produce...

vitamins B6, B12 and K

peristalsis

muscles push food down esophagus

segmentation

contractions in intestine and stomach that mix chyme

how long is the small intestine?

10 ft

villi

Fingerlike extensions that increase the surface area for absorption

microvilli

projections that increase the cell's surface area and have enzymes and pumps

after nutrients are absorbed they go to...

bloodstream (protein, short fats and carbs and O2 get taken to liver)

or

Lymph (fat and vitamins go to heart and cells)

gastroesophageal reflux

lower esophageal sphincter allows stomach content up

Ulcers

Open sores in the lining of the digestive system; inflammation and breakdown of stomach tissue; caused by H pylori, NSAIDS and extra stomach acid

Celiac Disease

disease caused by sensitivity to gluten; inflammation of small intestine that makes villi short

Steps of food safety

clean, separate, cook, chill

Danger zone

40-140 degrees

What helps prevent foodborne illness?

FDA standards, industry controls (HACCP system) and consumer awareness

causes of food borne illness

bacteria, viruses, parasites

common pathogens

salmonella, listeria, Hep A

how do environmental contaminants get on food?

it is absorbed by soil, pesticides during growth

examples of toxicants

heavy metals (lead and mercury), industrial chemicals, ag chemicals (pesticides and antibiotics), and arsenic

pesticides

promote crop survival but can leave harmful residue

common food additives

antimicrobial agents (salt, sugar nitrites), greater nutritional value (sweeteners; frutification and enrichment), antioxidants (freshness, vitamins and sulfates), Colors and Flavors (monosodium glutamine)

consumer concerns of water

worried about contaminants and lack of immunity to foreign water