Protein

Chemical Structure of proteins

Chemically, proteins are compounds made up of carbon, hydrogen, oxygen and nitrogen atoms. These atoms are bound together to form amino acids. Some amino acids may also contain sulfur. The amino acids link together to form proteins.

Essential and Non Essential Amino Acids

Proteins are composed from twenty amino acids. These twenty amino acids are categorized into essential and nonessential amino acids. Essential amino acids are the amino acids that the body is not able to make or not able to make in sufficient amounts to meet its needs. Therefore the essential amino acids must come from the diet. There are nine essential amino acids in normal healthy individuals. Nonessential amino acids can be synthesized in the body from carbohydrates, fats and nitrogen. The body must have the nutrients in sufficient amounts to manufacture nonessential amino acids. In some in-born errors of metabolism, nonessential amino acids become essential. Phenylketonuria (PKU) is an example of an in-born error of metabolism. With PKU the body normally uses the essential amino acid phenylalanine to make tyrosine, a nonessential amino acid but they are not able to convert phenylalanine to tyrosine. Tyrosine then becomes essential.

Essential Amino Acids

  • Histidine
  • Isoleucine
  • Leucine
  • Lysine
  • Methionine
  • Phenylalanine
  • Threonine
  • Trypotophan
  • Valine


Nonessential Amino Acids

  • Alanine
  • Arginine
  • Asparagine
  • Asprtic Acid
  • Cysteine
  • Glutamic Acid
  • Glutamine
  • Glycine
  • Proline
  • Serine
  • Tyrosine


Protein Means “Of Prime Importance”

Protein means “of prime importance”. Without protein your bones, hair, and skin would have no structure. Lacking adequate protein may lead to impaired bodily functions. Your red blood cells will not be able to clot. Your body would not be able to defend against infections. Protein is vital for so many of your basic functions.

Examples of Functions of Protein in your body:

Growth and maintenance
Protein is required daily for growth and maintenance. Each integral part of your body is either, growing, repairing or maintaining. For this your skin, muscles, organs, and bones need much more protein. Children and women who are pregnant have an increased need for protein during growth.

Enzymes
Proteins are necessary to produce enzymes. Enzymes can aid in chemical reactions within our body. Digestive enzymes are just one type of enzyme found in your body. Digestive enzymes assist in breaking down food during digestion.

Hormones
Many hormones are made up of proteins. Hormones assist your body in regulating body processes. Insulin is an example of a hormone produced in your body

Fluid Balance
Proteins are necessary for fluid balance. Inadequate protein can result in the body’s lack of ability to move fluids in and out of cells. When fluids build up in excess amount inside the cell it may cause edema

Acid-base balance
Proteins are necessary to maintain the body’s proper acid-base balance. An example of improper balance of acid-balance would be the body’s ability to maintain its blood system in the proper acid-balance base. Without the proper balance of acid-balance in the blood system the body could go into acidosis or alkalosis. Both can lead to coma and death

Transportation
Proteins often work as transporters within the body. Lipids, vitamins, minerals and oxygen all use transporters to circulate within the body

Antibodies
Proteins are necessary to build antibodies. Antibodies work to protect our bodies against foreign invaders. Without adequate protein our bodies’ resistance to protect against infection is decreased.

Energy and Glucose
Proteins do provide our body with some fuel. Excess protein can be converted to glucose to be used for energy.

Recommended Intakes of Protein.

The protein RDA for adults is .8 grams per kilogram of a HEALTHY body weight person. Individual protein needs may be difficult to establish and may require the assistance of a Registered Dietitian.

The right amount of protein for many people may be altered due to their current nutritional status. Factors that might affect protein requirements include:

  • Age
  • Weight
  • Body Composition
  • Skin Condition
  • Infection
  • Cancer
  • And so much more….


Most people in the United States get plenty of protein. In fact many get an over abundance of protein. Individuals who consume a large quantity of protein, especially in the form of meat, are putting themselves at risk for a high fat diet. High fat diets have been linked to heart disease, diabetes and cancer. High protein diets are not recommended. The long-term effects of high protein diets are not yet known.

Good Sources of Protein:

Beef, Chicken, Pork, Fish, Eggs, Ham, Lamb, Veal, Bison, Rabbit, Venison,

Beans, Peas, Nuts and Seeds

Vegetarian diets

Many people are turning to vegetarian diets. Vegetarian diets can be healthy as long as they are done properly. Vegetarians need to pay close attention to their diets to ensure they are meeting their daily requirements.

Types of Vegetarian Diets

  • Lactovegetarians- consume milk and milk products but exclude meat, poultry, fish, seafood and eggs
  • Lacto-ovu-vegetarians- consume milk, milk products, and eggs but exclude meat, poultry, fish and seafood
  • Macrobiotic diets: this is an extremely restrictive diet limited to a few grains and vegetables.
  • Vegan- excludes all animal derived foods. Vegan vegetarians get their proteins by combining plant-based foods that are high in protein


Thinking of changing your diet?

Seek the advice of Registered Dietitian to ensure you are meeting your nutritional needs.