Nutrition Review - Chapter 1

Dietary Reference Intake

a set of values for dietary nutrient intakes of healthy people used for planning diets to protect against nutrient deficiencies and chronic diseases

Estimated Average Requirement

the amount of a nutrient that will maintain a specific biochemical or physiological function of half of the people in a certain age and gender group

Recommended Dietary Allowances

average amount of a nutrient considered adequate to meet needs of almost all (98%) of healthy people

Adequate Intakes

average amount of a nutrient that appears sufficient to maintain health; insufficient evidence for an EAR; may be used as a nutrient intake goal

Tolerable upper intake levels

the max amount of a nutrient that is safe for no adverse health effects to occur

Carbs?

Organic and a macronutrient

Protein

Organic and a macronutrient

Fat

Organic and a macronutrient

Vitamins

Organic and a micronutrient

Minerals

Inorganic and a micronutrient

Water

Inorganic and not a nutrient

Organic

Compounds that contain carbon

Inorganic

Do not contain carbon

Macronutrients

Our body requires them in relatively large amounts

Micronutrients

Our body requires only in small amounts

Epidemiological studies

research the incidence, distribution, and control of diseases in population

Cross-sectional

study what types of food and how much certain groups of people eat

Case-control study

compare those with and without a certain condition- closely match in age/ gender so variables can be seen

Cohort

researchers analyze data from a selected group of people over a certain time

Lab based animal studies

feed animals special diets that provide or omit certain nutrients and observe any changes in health; test possible disease cause and treatments in a controlled environment

Lab based in vitro studies

researchers examine the effects of a specific variable on a cell, molecule isolated from a living organism

Human intervention (human trials)

ask people to adopt a new behavior

How many kcals/gram is in Fats?

9 kcals/gram

How many kcals/gram is in Protein?

4 kcals/gram

How many kcals/gram is in Carbohydrates?

4 kcals/gram

How many kcals/gram is in Alcohol?

Alcohol is not a nutrient but yields 7 kcals/gram

Fortified

addition to a food of nutrients that were either not originally present or present in insignificant amounts

Enriched

addition to a food of specific nutrients to replace losses that occur during processing so that the food will meet a specific standard. Ex. Iron, thiamin, riboflavin, niacin, folate

Functional foods

suggesting foods provide health benefits beyond their nutrient contributions- includes whole foods, fortified, and enriched foods- ex. Whole grains provide fiber

Phytochemicals

non-nutrient compounds found in plants, some have biological activity in the body- act as antioxidants, suppress inflammation, may protect against certain diseases

Energy density

measure of the energy a food provides relative to the weight of the food

Nutrient density

measure of nutrients a food provides relative to the energy it provides

Whole grain

a grain that maintains the same relative proportions of starch endosperm, germ and bran as the original; not refined

Daily value

expressed a percentage; ballpark estimate of contribution to total diet, based on 2000 kcals per day

Above 20%

High or excellent source

10-19%

Good source

Less than 5%

Low source

Nutrient claims

meet FDA definitions, statement that characterizes the quantity of a nutrient in a food

Healthy claims

describe a relationship between a food and a disease for health based condition; FDA authorized if there is enough scientific evidence to prove

Structure Function Claims

can be made without FDA approval; must not mention disease or symptom; can be deceiving while still being legal

Mouth

begins digestive process (motility and secretion); salivary glands secrete saliva which has digestive enzyme for starch (salivary amylase); pharynx: short tube shared by digestive and respiratory system; epiglottis: protects airway during swallowing

Esophagus

"food pipe", primary function is motility

Stomach

retains bolus in upper portion and transfers to lower portion little by little; adds acids, enzymes, fluid to bolus making chyme; chyme released into duodenum

Small intestine

-3 parts in order: duodenum, jejunum, ileum

-Common bile duct opens into SI allowing secretions from pancreas and gall bladder to enter SI

-Pancreatic duct: conducts pancreatic juices (enzymes, bicarbonate) from pancreas to SI

-Enzymes digest all energy yielding nutrients

-Major site of nutrient absorption

Large intestine (Colon)

reabsorbs water and minerals; withdraw water from chyme and leaves semisolid waste

Rectum

muscular terminal part of the intestine, extending from sigmoid colon to anus

Anus

final sphincter muscle and terminal outlet of the GI tract to pass stool (feces) out of body

Upper esophageal sphincter

opens during swallowing

Lower esophageal sphincter (cardiac)

prevents reflux- may cause indigestion and heartburn

Pyloric sphincter

chyme is released from the stomach into the small intestine

Ileocecal valve

separates small and large intestine

Bile

emulsifier brings fats into suspension with water, produced by the liver and stored in the gall bladder

Salivary amylase

secreted by saliva in the. Mouth, fluid eases swallowing and breaks down some carbohydrates

Pancreatic enzymes

break down carbs, fats, and proteins, secreted into small intestine

Gastrin

responds to food in stomach, secreted from stomach wall, hydrochloric acid is secreted into the stomach to maintain an acidic pH

Secretin

responds to acidic chyme in the small intestine, secreted from duodenal wall, stimulates the pancreas for bicarbonate rich juices to secrete into the small intestine to maintain slightly alkaline pH

Cholecystokinin

responds to fat or protein in the s intestine, secreted from intestinal wall, bile is secreted into duodenum to emulsify fats, bicarbonate and enzyme rich juices secreted into the small intestine to maintain a slightly alkaline ph, digest fats and proteins

Parts of the GI tract in order?

Mouth, esophagus, stomach, small intestine, large intestine, rectum, anus

Digestion/absorbtion of protein

digested in stomach, hydrochloric acid uncoils proteins, small amounts are absorbed through cells of the small intestine into hepatic portal vein

Digestion/absorption of carbohydrates

begin digestion in mouth by salivary amylase, pancreatic enzymes in small intestine finish digestion and begin absorption through intestinal walls into hepatic portal vein

Digestion/absorption of Fat

must be emulsified with bile in order to be digested, pancreatic and intestinal enzymes break down and begin absorption through small intestine into lymph

Where does protein go after absorption?

Hepatic portal vein

Where does carbohydrates go after absorption?

Hepatic portal vein

Where does fat go after absorption?

-Small lipids: bloodstream

-Large lipids (monoglycerides and long chain fatty acids): lymphatic system collects in thoracic duct and drains into subclavian vein then into bloodstream

Prebiotic

food components that are not digested by the human body but are used as food by the GI bacteria to promote growth and activity

Ex. Fruits and vegetables and whole grains such as bananas, onions, garlic, asparagus

Probiotic

"good bacteria", life cultures like naturally found in gut

Ex. Fermented dairy foods such as yogurt, aged cheeses, kimichi, sauerkraut, miso, tempeh

Choking

food slips into trachea and cuts off breathing; take small bites of food, chew thoroughly before swallowing

Diarrhea

intestinal contents moved too quickly for fluid absorption to occur, avoid strenuous activity, rest, drink fluids to replace losses

Constipation

causes are lifestyle or side affect of medication; treatment: fiber and water, physical activity, defecate when needed

Heartburn

eat small meals, sit up while eating, don't lie down 3 hours after eating or exercise 2 hours after eating, avoid fatty meals

Ulcer

take medicine, avoid coffee and alcohol, avoid foods that aggravate ulcer, minimize aspirin, ibuprofen, and smoking