Bodybuilders, fitness enthusiasts, people fighting disease, and just the average Joe all require protein daily for normal body function. Proteins are composed of amino acids whether they come from a powder or a whole food, and once they are in the body, the body will utilize them the same way. The nutritional benefits of protein are essential for life, growth and repair. The recommended daily allowance of protein for adults is 0.8 to 1.7g per kg of body weight, depending on activity level.
Growth and Maintenance
Most every cell and structure of the body is composed of in part by protein. Proteins are referred to as the building blocks of the body. For example, the protein collagen forms the matrix for bones, provides the tissue for tendons and ligaments, and strengthens artery walls.
Muscle cells must synthesize protein from amino acids provided by dietary protein to grow bigger (hypertrophy) and stronger. The muscle proteins formed are called actin and myosin. According to the sliding filament theory, actin and myosin are protein filaments that work in synergy to produce force from muscle. According to "Essentials of Strength Training and Conditioning" by Thomas Baechle and Roger Earle, an increase in the number of these filaments is due to an increase in strength training and adequate protein intake.
Cell turnover is a daily process for the body. Cells are largely composed of proteins. Cells from the skin, hair, fingernails and the digestive tract die and slough off daily. Cells made mainly by or from protein replace the sloughed-off cells. This turnover of cells keeps the body in a continual state of repair and growth, and thus a need for protein.
Catalyze Chemical Reactions
Proteins serve as enzymes to many chemical reactions in the body. Enzymes speed up the rate at which a chemical reaction occurs, making the body more efficient. Without enzymes, many reactions in the body are so slow that they would never be completed.
Convey Biological Signals
Proteins comprise many hormones such as growth hormone, insulin, glucagons, thyroxine and antidiuretic hormone. The body uses hormones as chemical messengers. These messengers are secreted by the endocrine glands when stimulated by a particular condition in the body. Once released, the hormone travels to one or several specific organs to elicit a particular response to counteract the altered condition.
Disease Prevention
Antibodies, the body's defense against disease, are large protein molecules. With adequate protein intake, the body is able to maintain an army of antibodies fighting off disease, thus building and strengthening immunity.
Other Benefits
Other benefits of protein include proper balance of body fluids through the use of plasma proteins; maintenance of the body's fluid acid-base balance by acting as a buffer; transportation of lipids, minerals, vitamins and other molecules around the body; proper blood clotting when injured; and helping to convey the sense of light to the brain through the protein opsin in the retina.
References
- Understanding Nutrition; Ellie Whitney and Sharon Rady Rolfes; 2005
- Essentials of Strength Training and Conditioning; Thomas R. Baechle and Roger W. Earle
Member Comments