Foods and Nutrition Midterm 1

Nutrition

a source of materials to nourish the body

Inorganic

not containing carbon or pertaining to living things

Organic

A substance or molecule containing carbon, carbon bonds, or carbon-hydrogen bonds.

Energy- yielding nutrients

The nutrients that break down to yield energy the body can use: carbohydrates, fat and protein.

calories

Unit be which energy is measured.

kilocalories

Food energy is measured by. 1000 calories = 1 kilocalorie. One kcal is the amount of heat needed to raise the temperature of 1 kg of water 1 degree Celsius.

Energy density

A measure of the energy a food provides relative to the amount of food (kcals per gram)

Carbohydrate

4 kcals of energy per gram

Fat

9 kcals of energy per gram

Protein

4 kcals of energy per gram

Metabolism

The process by which nutrients are broken down to yield energy or used to make body structures.

Vitamins

Organic, essential nutrients required in small amounts by the body for health.

Minerals

Inorganic materials, some minerals are essential nutrients required in small amounts by the body for health.

Six classes of nutrients

Carbohydrates, lipids (fats), proteins, vitamins, minerals, and water.

Nutritional genomics

The science of how nutrients affect the activities of genes, and how genes effect the interactions between diet and exercise.

Scientific method - Observation

Identify a problem to be solved or a specific question to be answered.

Scientific method - Hypothesis

An educated guess

Scientific method - Experiment

Design a study and conduct the research to collect data.

Experimental Group

This group receives the real treatment.

Control Group

This group receives a placebo.

Blind experiment

an experiment when the subjects do not know whether they are the experimental or control group.

Double-blind experiment

An experiment when neither the subjects or the researchers know who is the experimental or control group until experiment is over.

Theory

A tentative explanation that integrates many findings to further understanding of topic.

Variables

Factors that can change.

Malnutrition

Any condition caused by excess or deficient food energy or nutrient intake or by an imbalance of nutrients.

Nutrition Assessment

An analysis of a persons nutrition status that uses health, socioeconomic, drug and diet histories, anthropometric measurements, physical exams, and lab tests.

Primary Deficiency

A nutrient deficiency caused by an inadequate dietary intake of a nutrient

Secondary Deficiency

A nutrient deficiency caused by something other than an inadequate intake such as a disease condition or drug interaction that reduces absorption, accelerates use, hastens excretion, or destroys the nutrient (something happening in the body)

Subclinical Deficiency

A deficiency in the early stages, before the outward signs have appeared

Chronic Diseases

Diseases characterized by a slow progression and long duration.

Risk Factor

Any action or condition that increases the likelihood of injury, disease, or other negative outcome

Adequacy

The diet provides all the essential nutrients, fiber, and energy in amounts sufficient to maintain health.

Balance of a diet

Consuming enough but not too much of each type of food.

kCalorie Energy Control

Energy in = energy out.

Nutrient Density

A measure of the nutrients a food provides relative to the energy it provides. The more nutrients and the fewer kcalories, the higher the nutrient density.

Empty-kcalorie foods

Foods that contribute energy but lack protein, vitamins, and minerals.

Moderation

Food that provides enough but not too much of a substance

Variety

Eating a wide selection of foods within and among the major food groups

Five main food groups

Fruits, vegetables, grains, dairy, and protein.

Discretionary kcalorie allowance

The kcalories remaining in a person's energy allowance after consuming enough nutrient-dense foods to meet all nutrient needs for a day.

Processed Foods

Food that has been treated to change their physical, chemical, microbiological, or sensory properties.

Fortified Foods

Foods with nutrients added to them that were not orginally present.

Refined

The process by which the coarse parts of a food are removed.

Enriched

The addition to a food of nutrients that were lost during processing so that the food will meet a specified standard.

Whole grain

a grain milled in its entirety (all but the husk), not refined

Grain enrichment nutrients

Iron, thiamin, riboflavin, niacin, and folate.

Imitation Foods

Foods that substitute for and resemble another food, but are nutritionally inferior to it with respect to vitamin, mineral, or protein content. If the substitute is not inferior to the food it resembles and if its name provides an accurate description of the product, it need not be labeled "imitation."

Daily Values (DV)

Reference values developed by the FDA specifically for use on food labels.

Nutrient Claims

Statements that characterize the quantity of a nutrient in a food.

Digestion

the process by which food is broken down into absorbable units.

Absorption

the uptake of nutrients by the cells of the small intestine for transport into either the blood or the lymph

Lumen

the space between a vessel

Mouth

Chews and mixes food and saliva. Oral cavity containing the tongue and teeth.

Pharynx

the passageway leading from the mouth to the larynx and esophagus

Epiglottis

Protects airway during swallowing

Esophagus

the food pipe

Sphincter

a circular muscle surrounding, and able to close, a body opening

Esophageal Sphincter

a muscle at the upper or lower end of the esophagus, prevents backflow

Stomach

a muscular , elastic, saclike portion of the digestive tract the grinds and churns food, mixing it with acid and enzymes to form chyme

Pyloric Sphincter

the circular motion that separates the stomach from the small intestine and regulates the flow of partially digested food into the small intestine

Small intestine

a small diameter intestine is the major site of digestion of food, and absorption of nutrients. Segments are duodenum, jejunum, and ileum. Secretes enzymes that digest all energy yielding nutrients to smaller particles.

Gallbladder

the organ that stores and concentrates bile. When it receives the signal that fat is present in the duodenum, the gallbladder contracts and squirts bile through the bile duct and the duodenum.

Pancreas

a gland that secretes digestive enzymes and juices into the duodenum.

Ileocecal valve

the sphincter separating the small and large intestine. Prevents backflow from large.

Large intestine

the lower portion of the intestine that completes the digestive process. It segments are the ascending, transverse, the descending, and the sigmoid colon.

Appendix

a narrow blind sac extending from the beginning of the colon that stores lymph cells

Rectum

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

Anus

the terminal outlet of the GI tract

Digestive system

all the organs and glands associated with the ingestion and digestion of food

Bolus

the amount of food swallowed at one time

Chyme

the semi--liquid mass of partly digested food expelled by the stomach into the duodenum

Peristalsis

wavelike muscular contractions of the GI tract that pushes food along

Segmentation

a periodic squeezing or portioning of the intestine at intervals along its length by circular muscles.

Reflux

abnormal backward flow

Catalyst

a substance that initiates or accelerates a chemical reaction without itself being affected

Digestive enzymes

proteins found in digestive juices that act on food substances, causing them to break down into simpler compounds

-ase

denotes an enzyme

Carbohydrase

an enzyme that hydrolyzes carbohydrates

Lipase

enzyme that breaks down lipids

Protease

Enzyme that breaks down proteins

Hydrolysis

a chemical reaction in which water reacts with a compound to break up into more products

pH

a value that indicated the acidity or alkalinity of a solution on a scale of 0-14, based on the proportion of H+ ions.

0-7 pH

acidic. The lowest number has the highest H+ ion concentration

7 pH

pH neutral

7-14 pH

basic. lower the number of H+ concentration

Glands

cells or groups of cells that secrete material for uses in the body.

Exocrine glands

secretes their materials out

Endocrine glands

secretes their materials in

Saliva

liquid secreted into the mouth that contains mucus and digestive enzymes that start chemical digestion

Salivary glands

exocrine glands that secrete saliva into the mouth

Gastric glands

exocrine glands in the stomach wall that secrete gastric juice into the stomach.

Gastric juice

Secretion of the gastric glands within the stomach

Hydrochloric acid

composed of H+ and chloride (HCL) htat is produced by gastric glands

Mucus

a slimy substance produced in the nose and throat to moisten and protect them

Mucus Membrane

lines cavities that communicate with the outside. Contains glands that secrete mucus [mainly for lubrication]

Liver

the organ that manufactures bile

Bile

an emulsifier that prepares fat and oils for digestion. Secreted by the liver, stored in the gallbladder, and released in the small intestine.

Emulsifier

a substance with both water soluble and fat soluble portions that mixes fats and oils in a watery solution

Pancreatic juice

a fluid secreted into the duodenum by the pancreas containing enzymes for the digestion of carbs, fats, proteins and bicarb.

Bicarbonate

an alkaline compound with the formula HCO^3