Understanding Protein: Essential Functions and Dietary Needs

If a person were to eat a diet that provided carbohydrates, fat, and micronutrients, but very little protein, for example, if he or she ate only whole-wheat pita bread with olive oil, the body would break down muscle tissue to provide amino acids to make essential proteins.

Protein Intake and Recommended Dietary Allowance

If a man weighs 190 lb and eats 150 g protein per day, his protein intake is greater than 200% of the Recommended Dietary Allowance (RDA).

Protein Structure

Some proteins contain an alpha helix, which is part of their secondary structure.

Amino Acids

The most accurate statement about amino acids is that essential amino acids cannot be manufactured by body cells. Nonessential amino acids can be made by the liver from other amino acids.

Protein Sources and Equivalents

If a person usually ate 2 ounces of lean meat at lunchtime and decided to substitute cooked lentils instead, how much of the lentils would the person need to eat? 1/2 cup

Protein Denaturation

Body proteins may become denatured in the presence of a very high fever.

Hydrochloric Acid and Protein Digestion

The most important function of hydrochloric acid in the stomach is to convert pepsinogen to its active enzyme form, pepsin.

Catabolism and Injury

A patient fell off a bicycle and broke one arm and one leg. Immediately after the accident, the patient's body will be in a state of catabolism.

Vitamin B6 and Amino Acid Absorption

Without vitamin B6, the body would be unable to absorb amino acids.

Nitrogen Balance

An example of a situation in which nitrogen balance is positive is pregnancy.

Collagen Production

If a patient has a torn ligament, then during healing and recovery, the patient's body would need to manufacture collagen.

Antibody Production

During acute bacterial infections, patients need extra protein to manufacture antibodies.

Protein Buffering

The property of protein that is most important to its buffering properties is the fact that amino acids include both an acid carboxyl group and an amine base group.

Myoglobin

The protein found in muscles whose function is similar to that of hemoglobin in blood is myoglobin.

Phenylketonuria

For clients with phenylketonuria, the most important part of treatment is to limit their phenylalanine intake to the amount their bodies need.

Complete Protein Sources

An example of a food that contains complete protein is a hard-boiled egg.

Glucocorticoid Hormones

High levels of glucocorticoid hormones are likely to be produced by someone who has a large infected wound.

Complementary Proteins

An example of a meal that contains complementary proteins is split pea soup with crackers.

Urinary Urea Excretion

High urinary urea excretion may be caused by high protein intake.

Protein Needs for Athletes

Why do they need to provide more protein for the men's rowing team than for the women's rowing team? The men's team has more lean body mass than does the women's team.

Protein Intake in Physically Active Adults

Most physically active adults in America do not need to eat more protein than inactive adults because most people have high enough protein intake to provide the extra protein needed for active muscles.

RDA of Protein

The RDA of protein for a healthy adult who weighs 60 kg is 48 g/day.

Lactovegetarian Diet

Janet eats beans, grains, fruits, and vegetables, and milk. Her diet is considered lactovegetarian.

Vegetarian Diets and Supplementation

Eric follows a vegetarian eating pattern, and he wants to know whether he needs to take any vitamin and mineral supplements. What would be most important to find out? Whether he follows a vegan eating pattern or eats some animal foods.

Kosher Diet

A person who follows a strict kosher diet would not eat a cheeseburger and fries.

Serving Size of Meat

An appropriate size serving of meat, poultry, or fish is about the size of the palm of your hand.

Kwashiorkor

A small child has normal weight, but his arms and legs are thin, whereas his belly and face appear swollen. His mother tells you that the only food they have had in the house for the past 3 weeks is noodles and some bread. The child probably has kwashiorkor.

Risk for Malnutrition

Examples of individuals who may have an increased risk for malnutrition include children with chronic infections.

Lifestyle Habit of Chaining

An example of the lifestyle habit of "chaining" is eating a piece of fruit with breakfast every day.