L-Aspartic Acid

Aspartic Acid (and a close similar amino acid asparagine) is considered a non-essential amino acid. This however does not mean that under certain instances it is not vitally important. Aspartic acid is most well known for its role in the production of NutraSweet. There are many negative side effects from intake of this synthetic sweetener that are not seen in the natural form of the amino acid itself. In the human body aspartic acid is synthesized in the liver from glutamate and healthy bacteria. Aspartic acid is abbreviated as either ASP or by its one-letter abbreviation D with a weight of 114.11. Aspartic acid is synthesized in the liver from glutamate and is dependent upon vitamin B6 (pyridoxine) for this conversion. Asparagine is synthesized primarily from aspartic acid and ATP, but also can be manufactured from glutamic acid. Its manufacture from aspartic acid appears also to require the mineral magnesium.

Function- Aspartic acid is found in high concentrations throughout the brain and body. Aspartic acid, like glutamic acid, functions as a major excitory neurotransmitter in the brain, where it is mostly concentrated in the hypothalamus and hippocampus. A highly active form of aspartic acid known as N-acetylaspartic acid is considered the brain's most highly concentrated amino acid neurotransmitter. Asparagine, like glutamine, is needed to maintain balance between too much or too little stimulation in the central nervous system. When asparagines extra amino group is removed during its conversion back into aspartic acid, it releases energy that the central nervous system and brain can use.

Aspartic acid is necessary for the production of energy from the Krebs cycle and also triggers the urea cycle. In the Krebs cycle, carbohydrates are broken down for energy; aspartic acid helps activate the process by transporting energy into the mitochondria. Mitochondria are the "powerhouse of the cell," found in the cells of almost all living organisms that contain enzymes responsible for the conversion of food to usable energy. Aspartic acid helps stimulate the urea cycle, where waste products from protein metabolism are detoxified and formed into urea, by helping to form carbamyl phosphate (CP) which is the key enzyme needed to start the urea cycle. It also helps the removal of excess ammonia and nitrogen.

In proper balance, aspartic acid is beneficial for brain and neural disorders. It has been found in increased levels in persons with epilepsy and in decreased levels in people with some types of depression. It is good for athletes and helps to protect the liver by aiding in the removal of excess ammonia. Aspartic acid combines with other amino acids to form molecules that absorb toxins and remove them from the bloodstream. It helps to move certain minerals across the intestinal lining and into the blood and cells, aids cell function, and aids the function of RNA and DNA, which are the carriers of genetic information. It enhances the production of immunoglobulins and antibodies.

Deficiency- Since aspartic acid plays a vital role in the production of energy and detoxification of urea those suffering from fatigue, depression and lack of energy may be deficient in aspartic acid.

Sources- Like most amino acids, aspartic acid is highly concentrated in protein foods. Plant protein, especially which found in sprouting seeds, contains an abundance of aspartic acid. Natural sources of aspartic acid include almonds, avocados, bananas, pork, wild game, turkey, fish, cottage cheese, lima beans, and ricotta cheese.

Precautions- At proper doses aspartic acid is beneficial to exciting nerve cells, however, if high levels of aspartic acid are present it can cause over stimulation and cell damage. If you are taking a balance of amino acids with cofactors this should not be a major concern. An amino acid profile (lab test) can be very beneficial in safely, efficiently and accurately determining amino acid need.

Requirements- There is no Recommended Dietary Allowances (RDA) listed. Individual needs may differ due to clinical conditions, biochemical individuality and absorption. All sources of nutrients should be consumed in their most natural state, in the form of a variety of foods or supplements when necessary. Free form amino acid supplements are immediately absorbed by the body and should be consumed with natural occurring cofactors for best results. Consulting with a physician that is properly trained in the natural healing sciences and amino acid therapy may be needed for optimum results.

Written by Jerome Rerucha D.C.

References-
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