Nutrition Exam 1

Nutrient Density

a measure of the nutrients provided by a food relative to its calorie content. Have a lot of vitamins and minerals compared to foods with fats or alcohol

Energy density

a measure of calories relative to the weight of the food. Small foods with a lot of calories. Looking at fat here.

Empty Calories

“junk foods”. Large portion of calories provided by fat, added sugar, and alcohol

Functional foods

Foods that contain physiologically active compounds that provide health and benefits beyond their nutrient contributions (designer foods, nutraceuticals)

Ex: Cholesterol free eggs, lactose free milk, calcium fortified juice, yogurt (good bacteria added)

Fortification

To add nutrients to foods. It began to help eliminate nutrient deficiencies in the population. Fed gov mandates that certain nutrients be added to certain foods.

Vitamins added to breakfast cereals, vitamin D to milk, etc.

Enrichment

Vitamins, minterals, and fiber were lost during processing ( w removal of germs, etc.), so the US gov requires that some of those lost nutrients be added back.

NOT the same as a whole grain.

Carbohydrates

\#1 fuel source for the body. Almost everything has carbs. Broken down into sugar.

Simple carbs

Easier to digest. Two types: monosaccharides (glucose, fructose, galactose), and disaccharides (maltose, sucrose, lactose)

Complex carbs

Starch: how plants store glucose. roots, seeds

Glycogen: how humans store glucose. muscles and liver

Fiber: Not digestible. Only found in plant foods. Men need 38 g per day, women need 25 g per day

Types of fiber

Soluble: dissolve in water; delays emptying and slows glucose absorption, protects against heart disease. Thickens stool. Banana, avocado

Insoluble: does not dissolve in water, does not thicken stool. This one absorbs water and bulks up. Speeds through GI. This type helps with constipation. Corn, spinach, kale, celery green veggies

Fats/lipids

Generally not water soluble (think oil in water). Fatty acids, triglycerides, phospholipids, cholesterol

Fatty acids

Saturated: each carbon has a hydrogen bonded. (linear in shape). Solid fat at room temp. butter, lard, coconut oil

Unsaturated: 2 carbons side by side are missing hydrogen atoms and are double bonded. Looks like a crooked line. They cant stack closely together, so it’s a liquid at room temp. Olive oil, other oils

Triglycerides

What we normally refer to as fat. Most common. Mix of saturated/unsaturated. More saturated = solid, less = liquid

Phospholipids

Partially water soluble. Looks like triglycerides chemically. egg yolk, pb, sorbeans

cholesterol

comes only from animal foods. produced in liver. makes cell membranes, bile. not essential. we dont have to eat it since its made in our liver. eggs, red meat, dairy, shellfish

Proteins

skin, hair, ligaments, tendons nee this. good for enzymes (makes chemical reactions in body), transport, immune safety, movement, hormones, fluid balance, energy.

essential vs non-essential amino acids

9 are considered essential. other are only essential if the body cant synthesize sufficient amounts.

denaturation

shape of protein is altered and protein can no longer function properly. permanent. making whip cream, cracking egg on skillet.

vitamins: fat-soluble

vitamins A, D, E, K. associates w lipids in food and body, need lipids to absorb them in body. stored in liver and fat. possible toxicity

vitamins: water soluble

vitamin b6, biotin, vitamin b12, vitamin c, thiamin, niacin, riboflavin, folate, panthothenic acid. dissolves in water. limited stores. excess filtered by kidney and peed out.

bioavailability

extent to which the body can absorb and use nutrients. absorption increases during infancy, adolescence, pregnancy/breastfeeding.

osmosis

diffusion of water through a selective permeable membrane

minerals

dont provide calories. elements in the earths rocks, soils, natural water.

major minerals

require 100mg or more per day. sodium, potassium

trace minerals

require less than 100 mg a day. iron, selenium, chromium

steps of scientific method

1 observations 2 hypothesis 3 experiment 4 analyze data and draw conclusions 5 report findings 6 conduct more research

4 types of epidemiological studies

cross sectional: measures exposure and outcome at one point in time. fast. interested in health outcome. could be diet, working out, smoking, sleep, etc.

cohort

identify people free of disease at beginning. collect info. compare exposures over that period of time to see what impacted changes

case-control

start w people who already have a disease/case. match 2 controls. identify differences between the two groups.

how to identify fad diet

usually some benefit, not great. often must purchase extra stuff. maybe weight comes off fast doesnt stay off.

phytochemicals

substances in plant foods studied for their effect on health and disease. antioxidants, anti-inflammatories, liver-health.

super foods

kinda a myth. whole foods with lots of vitamins and minerals and phytochemicals

function of antioxidants

substances that protext the body against oxidative damage (free radicals). good antioxidants beta-carotene, vitamin c, e, selenium

prebiotics

non digestible foods that are then food for probiotics, encourages growth in GI tract. onions, garlic, bananas, whole wheat

probiotics

live microorganisms that live in gut. improve GI. yogurt, fermented veggies, soy products.