Terms & Digestion

Food and NutritionSpring 2011

The Digestive System

Digestion: Process the body uses to break food into nutrients

Absorption: process by which nutrients get from the digestive tract into transportation system that

carries them to cells throughout the body

Food is broken down in the digestive tract or Alimentary Canal

7 Parts of the Digestive Tract

1. Mouth2. Esophagus3. Stomach

4. Small Intestine5. Large Intestine

6. Rectum7. Anus

Mouth

Sight, smell and taste of food stimulate the flow of a liquid called saliva.

Saliva’s job is to soften and moisten food.Swallowing is an involuntary reflex.

Esophagus

The tube that connects the mouth to the stomach.

Muscle contractions called peristalsis carry food along to

it’s next location.

Stomach

Churns and breaks down your meal and mixes it with gastric

juices.

The food now becomes a thin,

soupy mixture called chyme

Small IntestineDigestion ends here. This tube is 20 feet long

and is divided into 3 sections1. Duodenum2. Jejunum3. Ileum

Villi: hair like projections that increase the surface of the intestinal wall

The food has now been digested. It will now be absorbed by the blood stream.

Wastes will pass to the large intestine and later be eliminated.

Large IntestineThere are four sections:

1. Ascending Colon – goes up2. Transverse Colon – goes across3. Descending Colon – goes down

4. Sigmoid Colon – the “S” shaped partIts function is to absorb water from the remaining indigestible food

matter, and then to pass useless waste material from the body.

Rectum & Anus

Last Part of the Digestive System.Waste is eliminated through here.

Nutrition Terms

• RDA• Digestion• Nutrients• Fortified Foods• Nutrition• Dietary Supplements• Cholesterol

• Dehydration• Dietary Fiber• Complex

Carbohydrates• Calorie• Enriched Foods• Basal Metabolic Rate

Nutrition

The science of turning food into fuel for the

body

Nutrients

Provide materials for building and maintenance of body tissue, and regulate body processes.

6 Main NutrientsCarbohydrates

MineralsFat

VitaminsProteinWater

Organic Nutrients – any substance that contains carbon

Carbs – Minerals – Fat – Protein

Inorganic Nutrients – any substance that does not contain

carbonVitamins - Water

Energy

We get energy from 3 of the 4 organic nutrients1. Fats

2. Carbohydrates3. Protein

These Nutrients give us “fuel for our body!”

CaloriesA unit of energy is called a

CALORIE (kcal).An egg has 85 (kcals) calories

1 gm of Carbohydrate = 4 kcal

1 gm of protein = 4 kcal1 gm of fat = 9 kcal

RDA

The Recommended Dietary Allowance recommends that our diets have:

58% Carbohydrate – 30% Fat – 12% Protein

Carbohydrates

• Organic Nutrient• Body’s main source of energy• Provides fiber for digestion and elimination• Best Sources: bread, cereals, chips, fruits,

potatoes, rice, sweets and sugar

Proteins• Organic Nutrient• Body uses it to build and

repair tissue• Helps regulate body

processes• Helps make antibodies to

fight disease• Best Sources: Milk,

Cheese, Eggs, Poultry, Fish, Meat, Nuts, and Legumes

Fats

• Organic Nutrient• Carry fat-soluble vitamins

through the body• Some supply essential

fatty acids for normal growth and skin health

• Best sources: butter, margarine, lard, vegetable oil, and vegetable shortening

Vitamins

• Inorganic Nutrient• Each vitamin has it’s

special function.• They do not provide

energy or build body tissue, but they help regulate these processes

• Best Sources: Different in all foods

Minerals

• Organic Nutrient• Help regulate body

processes• Best Sources: different

in all foods

Water

• Inorganic Nutrients• Carries nutrients to the

body cells and carries waste products away

• Helps keep the body cool

• Best Sources: water