Protein

Nutrition & Wellness

What are Proteins?

Proteins: large complex molecules composed of amino acids. Contain carbon, hydrogen, oxygen, nitrogen Primary source of nitrogen in our diets 20 different amino acids are used to make

proteins Essential component of the body cells, tissues

and fluids. Building blocks of muscle, bone, skin, hair,

and virtually every other body part or tissue.

Why is protein so important in our diet?

Proteins are constantly needed to replace the wear and tear of the tissue and keep up the protein concentration in the blood serum. This is why the minimum amount of protein, from a good source, must be consumed daily.

Functions of Proteins

Cell growth, repair, and maintenance Enzymes Hormones Fluid and electrolyte balance pH balance Antibodies to protect against disease Energy source

What are Amino Acids?

Chemical building blocks from which new proteins are made.

How Are Proteins Made?

Proteins are long chains of amino acids.

Amino acids are joined to each other by peptide bonds.

The structure of each protein is dictated by the DNA of a gene.

Amino Acids

Essential amino acids Cannot be produced or stored by our bodies Must be obtained from food

Nonessential amino acids Can be made by our bodies

Proteins in the Diet

Incomplete protein: does not contain all nine essential amino acids. Not sufficient for growth and health Considered a “low quality” protein

Complete protein: contains sufficient amounts of all 9 essential amino acids. Support growth and maintenance of body tissues Considered a “high quality” protein Animal proteins: milk, eggs, cheese, fish and meat Plant sources: brewer's yeast, certain nuts,

soybeans/tofu, germ of grains

All protein is not equal

It is important to have a variety of foods to make certain the body gets all of the essential amino acids. There are various ways to make protein complete:

By combining plant and animal foods By combining plant proteins from a variety of cereals

and grains For example: peanut butter lacks 3 amino acids. By

spreading it on whole wheat bread and serving it with a glass of milk or some yogurt it becomes a complete protein.

Proteins in the Diet

Mutual supplementation: using two incomplete proteins together to make a complete protein.

Complementary proteins: two protein sources that together supply all 9 essential amino acids.

Example: beans and rice

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Complementary Food Combinations

Combinations to Create Complete Proteins

Combine Grains and Legumes Peanut butter on whole-wheat bread Rice and beans

Combine Grains and Nuts/Seeds Whole-wheat bun with sesame seeds

Combine Legumes and Nuts/Seeds Trail mix (peanuts and sunflower seeds)

Good Sources of Protein

High Quality/Complete Proteins

Vegetable proteins: dried peas, legumes, soy beans, grains and nuts

Animal proteins: milk, eggs, cheese, meats such as fish, poultry and beef

Nuts!

Excellent source of protein.

People who regularly consume nuts are less likely to have heart attacks or die from heart disease

Studies have shown a consistent 30% to 50% lower risk of sudden cardiac death, or cardiovascular disease associated with consuming nuts several times a week.

Are there hazards or concerns in eating too much protein? Converting large amounts of protein for

storage as fat creates products that may place dangerous stress on the liver and kidneys.

A very high protein diet may even cause dehydration as extra water is needed to dispose of the products of protein metabolism. Athletes and dancers are already at risk for dehydration and should be especially careful to avoid excess protein.

When do you need protein?

First meal of the day - to replenish amino acids used for growth and maintenance during the night.

Last meal of the day - to build up the protein in the body needed for repair and maintenance during the night.

What if there is a lack of protein in our diet?

Deficiencies of protein can cause: tiredness loss of weight lack of energy growth can be stunted in children decreased immunity and lower resistance to

disease Prolonged lack of protein can result in liver damage,

weakening of the heart and respiratory system, and eventual death may result.

Protein – Energy Malnutrition

Marasmus: disease resulting from severely inadequate intakes of protein, energy, and other nutrients.

Marasmus symptoms include Severe wasting of muscle tissue Stunted physical growth Stunted brain development Anemia

Protein – Energy Malnutrition

Kwashiorkor: disease resulting from extremely low protein intake.

Kwashiorkor symptoms include Some weight loss and muscle wasting Edema resulting in distention of the belly Retarded growth and development

Kwashiorkor is often seen in children in developing countries.

How much protein do we need each day?

Adults need a minimum of 1 gram of protein for every kilogram of body weight per day to keep from slowly breaking down their own tissues. This is about 9 grams of protein for every 20 pounds.

Consuming the right amount of protein

Proper protein intake depends on Activity level Age Health status

All protein packages are not created equal

6 oz. Porterhouse steak = 38 grams protein 44 grams of fat, 16 of them saturated 3/4 of the recommended daily intake for saturated fat.

6 oz. Salmon = 34 grams of protein 18 grams of fat, 4 of them saturated

1 cup of cooked lentils = 18 grams of protein, Under 1 gram of fat

Pay attention to your food choices. Stick with the leanest cuts of beef. Fish or poultry are excellent alternatives. Even better options are vegetable sources of protein, such as

beans, nuts, and whole grains.

Getting the minimum daily requirement of protein is easy each day

Breakfast - cereal with milk Lunch - a peanut butter and jelly sandwich Dinner - a piece of fish with a side of beans Totals to about 70 grams of protein

The Bottom Line: Vary your Protein

Get a good mix of proteins. Add walnuts, pecans, cashews for a snack. Add vegetable proteins to your diet to reduce

fat intake. Eat a variety of foods to ensure you get all of

the amino acids you need for complete proteins.