Protein can also be used for energy, but the first job is to help with making hormones, muscle, and other proteins. Broken down into amino acids , used to build muscle and to make other proteins that are essential for the body to function.
Broken down into fatty acids to make cell linings and hormones. Extra is stored in fat cells. After a meal, the blood sugar glucose level rises as carbohydrate is digested.
This signals the beta cells of the pancreas to release insulin into the bloodstream. Insulin helps glucose enter the body's cells to be used for energy. If all the glucose is not needed for energy, some of it is stored in fat cells and in the liver as glycogen. As sugar moves from the blood to the cells, the blood glucose level returns to a normal between-meal range. When the blood sugar level falls below that range, which may happen between meals, the body has at least three ways of reacting:.
Other hormones can raise the blood sugar level, including epinephrine also called adrenaline and cortisol released by the adrenal glands and growth hormone released by the pituitary gland. Author: Healthwise Staff. Medical Review: E. This information does not replace the advice of a doctor.
This process is called gluconeogenesis, meaning production of new glucose. Gluconeogensis is not cost-effective for the body because it requires more energy than simply using available glucose. Think of it this way: Using amino acids instead of carbohydrates for fuel is like using a piece of fine jewelry to pay for groceries when you have cash on hand. When muscle is stressed, as in exercise, amino acids are needed to repair and build the tissue to strengthen it.
The more this occurs, the more muscle mass is built. Eating more protein alone does not make this happen, although adequate amounts are needed in exercise to support muscle growth.
Muscle is viewed as a structural, not a storage, form of protein. A constant pool of amino acids in the blood is broken down and synthesized into whatever amino acids or compounds the body requires. Muscle is not broken down for fuel -- the body does everything, including using fat stores first, to preserve it in times of starvation or dieting.
Arguably the most important role of amino acids in the body is synthesis of a variety of compounds the body uses. Hormones, enzymes, immune factors, neurotransmitters and other amino acids are all synthesized from dietary protein. Amino acids combine, convert and activate with other compounds to synthesize new ones. It all is regulated by what the body needs at that moment. In striving to excel at their respective sports, many athletes subscribe to the notion that protein supplements enhance their physical performance.
The existence of a multi-billion dollar supplement industry, however, does not prove that such products are necessary. Only a rigorous scientific investigation can do that. Legally, dietary supplements cannot claim to cure, treat or prevent a disease, although they can convey how they potentially affect the body. Supplements do not have to go through the same regulatory process as drugs which undergo a thorough assessment for safety and efficacy before going on the market.
Protein supplements therefore do not have to be proven effective before being sold. Indeed, their effectiveness continues to be a matter of ongoing debate, and with a lack of concrete evidence, many people continue to invest in this growing market.
A normal adult requires only forty to fifty grams of protein per day in order to supply essential amino acids and replace the nitrogen eliminated in urea as waste. Essential amino acids are the nine out of twenty amino acids that the body requires but cannot produce on its own. When an amino acid is broken down, the nitrogen it contains is converted into urea by the liver which then is excreted via the kidneys. Supposedly, the amino acids arginine and ornithine promote release of growth hormone, a natural hormone that stimulates muscle development.
Glutamine and carnitine have also been marketed as strength-enhancing amino acids. By taking large quantities of these proteins, athletes hope to be able to run that extra mile or lift that extra weight without failing their drug tests.
But, does it work? More importantly, is it worth the risks? A typical American diet contains approximately seventy to ninety grams of protein per day, meaning that most individuals far surpass their daily protein requirements. Dietary protein is used to replace proteins which were previously broken down and used by the body. Extra protein does not get stored. Instead, excess amino acids get converted to carbohydrate or fat.
Thus, it seems that additional protein intake will not directly increase muscle growth, strength or physical performance and could even lead to weight gain and fat deposition, which are surely negative consequences for any athlete.
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