4Ever Fit L-Arginine 500mg
The study of amino acids is making a major contribution to the understanding of diseases. Amino acid therapies have been used successfully to prevent aging, prevent heart disease, enhance memory, eliminate depression, control stress, improve sleep, relieve arthritis, reduce herpes, arrest alcoholism, manage allergies, and promote hair growth.1 Arginine has been linked to enhanced immunity, the release of the Human Growth Hormone (HGH), greater muscle mass, rapid healing from injury, increased sexual potency, and helping to reverse atherosclerosis.2 Sometimes one amino acid can cancel the effect of another. For example, arginine is reported to have an antagonistic relationship with lysine.1 On the other hand, arginine has a complementary relationship with ornithine, citrulline, and aspartic acid.
Dietary arginine is found in chocolate, wheat germ and flour, buckwheat, granola, oatmeal, dairy products (cottage cheese, ricotta, nonfat dry milk, skim yogurt), beef (roasts, steaks), pork (Canadian bacon, ham), nuts (coconut, pecans, cashews, walnuts, almonds, Brazil nuts, hazel nuts, peanuts), seeds (pumpkin, sesame, sunflower), poultry (chicken and turkey light meat), wild game (pheasant, quail), seafood (halibut, lobster, salmon, shrimp, snails, tuna in water), chick peas, and cooked soybeans.2,11
Signs of Deficiency
Deficiency produces symptoms of muscle weakness, similar to muscular dystrophy.1 Arginine-deficiency impairs insulin production, glucose production, and liver lipid metabolism.3 Conditional deficiencies of arginine or ornithine are associated with the presence of excessive ammonia in the blood, excessive lysine, rapid growth, pregnancy, trauma, or protein deficiency and malnutrition. Arginine deficiency is also associated with rash, hair loss and hair breakage, poor wound healing, constipation, fatty liver, hepatic cirrhosis, and hepatic coma.1
Substantially increasing consumption of dietary protein (meats, dairy products, etc.) to ensure optimal levels of circulating amino acids may prove to be unhealthy because excessive dietary protein places stress on the liver and kidneys, which process the waste products of protein metabolism.2 In addition, protein-rich foods often are rich in fats, which may cause unwanted weight gain and an unfavorable cholesterol profile.
Arginine, like most amino acids, can have one of two forms, called the L-form and the D-form. These two forms are mirror images of each other, with the L-form molecule rotating in a spiral to the left (L for "levo" which is Latin for "left") and the D-form spiralling to the right (D for "dextro," Latin for "right"). The L-form of arginine (and most other amino acids) is more compatible with human biochemistry, such that L-arginine is the only form recommended.3
Most researchers recommend the free (also called undigested) forms of amino acids, which do not need to be digested and are absorbed directly into the blood for distribution throughout the body. In hospital settings, arginine may be prescribed for therapeutic purposes in the forms of di-peptides, tri-peptides, or hydrolysates, but generally the free form is considered best, particularly the L-form.1
Some nutrition scientists advise that supplementation of L-arginine and lysine may have mutually negating effects such that the benefits of neither are full expressed. Other experts, however, recommend "stacking" (taking more than individual amino acid supplements at the same time) to boost their effects, such as arginine and lysine supplements taken together to amplify the effects of both, for example: reportedly increasing HGH release by four times that of arginine alone.8 Another researcher suggests supplementation of dietary amino acids should be based on the combination of L-arginine, L-lysine, and L-ornithine to stimulate HGH production.12 According to Medical Director Giampapa of the Longevity Institute International (in Montclair, New Jersey), the optimal oral daily supplementation of amino acids should include 2 grams arginine plus 2 grams ornithine plus 1 gram lysine plus 1 gram glutamine.8 Further studies are required to determine optimal dosages and combinations of dosages.
To achieve greatest effectiveness as an HGH releaser, L-arginine should be consumed on an empty stomach at bedtime.6, 13 HGH release occurs 30-60 minutes after falling asleep, and also during and just following vigorous exercise.4
Why People Take It
Arthritis. Found in high concentrations in the connective tissues, arginine is a component of collagen that plays a vital role in the production of new tissue and bone cells.3
Arginine may prove helpful in treating Alzheimer's, because it raises polyamine levels.1
Arginine retards tumor growth by enhancing immune function.3, 9 Arginine increases the size and activity of the thymus gland, which produces T-cells. Large doses of arginine can lower polyamines, which are present in various cancers in elevated levels.1 Arginine has been found to inhibit the growth of several types of tumors in laboratory mice.
Arginine aids in liver detoxification by neutralizing ammonia, and may benefit in the treatment of liver disorders such as liver injury, hepatic cirrhosis, and fatty liver degeneration.1, 3, 9
Arginine facilitates a reduction in body fat, while increasing lean muscle mass.3 Arginine inhibits the absorption of dietary fat.
More than fifty research studies reportedly support the value of arginine supplementation for athletes.4 Arginine is considered to be key to efficient muscle metabolism because of its role in the transport, storage, and elimination of nitrogen. Creatine is derived from arginine, as are guanidophosphate and phosphoarginine, all of which have roles in muscle metabolism.
After a vigorous workout, the body has increased testosterone and HGH production for a period lasting approximately two hours. During this timeframe, dietary arginine and ornithine can contribute to a hormonal environment that produces increased protein synthesis and muscle growth.14
Seminal fluid contains substantial quantities of arginine, and arginine may be beneficial in treating sterility in men.13 In one study, men with low sperm counts took 4 grams of arginine orally, with 80% of the men showing significant improvement, in some cases resulting in pregnancies.9 Arginine is also noted by one researcher for its ability to increase libido and induce erections.7, 8 Arginine, ornithine, and aspartic acid have been shown to have a positive effect on sperm viability and motility.1
Inherited Urea Cycle Disorders (Rare). Arginine therapy is employed in the treatment of arginemia, citrullinemia, and argininosuccinic aciduria.1
Arginine is involved in the production of variety of enzymes and hormones. Arginine facilitates the release of HGH, stimulates the pancreas for insulin production, and is a component in the hormone vasopressin produced by the pituitary gland.3 One mechanism for arginine as an HGH releaser may be its capacity for blocking secretion of the HGH-inhibitor: somatostatin.8
HGH-release by means of arginine may offer benefits in the treatment of fractures and injuries, as well strengthening the immune system, building lean muscle, burning fat, and reversing many of the effects of aging.9
The elderly respond to arginine with substantially increased levels of glucose and growth hormone.1 A study at the Division of Endocrinology at the University of Turin involving normal adults aged 66-82 who tripled the level of HGH in their blood after administration of 30-gram injections of arginine.4, 8
Arginine is essential for optimum growth and in the regulation of protein metabolism.1 The main source of energy for muscle and other cells is glucose, but glucose metabolism produces ammonia, which is toxic unless rapidly converted to another compound. The primary metabolic role of arginine is in stimulating the enzyme that starts the urea cycle, which converts ammonia into a less toxic compound called urea that the blood carries to the kidneys for excretion.
As a cholesterol fighter, a high ratio of arginine-to-lysine is recommended.1 In the urea cycle, citrulline is a precursor of arginine, so it may be that foods rich in citrulline (onions, scallions, garlic) lower cholesterol because the citrulline is converted to arginine in the body.
As a booster of the immune system, arginine stimulates the thymus and promotes lymphocyte production.9, 10 This may be the key to arginine's ability to promote healing of burns and other wounds. During stress (good or bad), the thymus gland typically shrinks, and sickness results; however, arginine facilitates the maintenance of the gland's proper size and normal production of lymphocytes.15
In support of brain function, arginine is believed to serve as a precursor to nitric oxide (NO), a neurotransmitter.1 Nitric oxide plays a role in the dilation and constriction of small blood vessels in brain. Therefore, arginine may have a positive effect on cerebral circulation. Arginine pyroglutamate is cited for having cognitive-enhancing effects.16
Related to its neurotransmitter function and its role as a precursor of NO, L-arginine has been noted for its critical role in stimulating healthy sex drive and enhanced sexual performance in men.7
In summary, L-arginine is one of the most powerful tools in any anti-aging program because of its functional value in promoting the production of HGH and other hormones, strengthening the immune system, improving lean muscle mass and reducing fat, regulating several vital metabolic processes, improving cholesterol profiles, supporting brain function, and enhancing sexuality. Hundreds of studies have been undertaken to date, and clearly arginine merits further research.
The toxicity level for amino acids is 50 to 500 times the therapeutic dose range.1
High-dose arginine supplementation may result in watery diarrhea and sometimes stomach cramps and headaches.
Individuals with herpes and other viral infections should not take arginine supplements, because arginine seems to promote the viral growth.3, 17
Persons diagnosed as having schizophrenia are advised to avoid dietary supplementation of arginine above 30 milligrams per day.2, 3
According to one physician, doses greater than 40 grams per day may pose dangers to patients with liver and kidney disease.1 Another expert advises against any arginine for patients with liver and kidney disease without the permission of a physician.9
Arginine supplementation is not advised for pregnant women or nursing mothers2, nor should supplemental amino acids be administered to a child.3, 9
 Braverman, M.D., E.R, The Healing Nutrients Within (New Canaan, CT: Keats Publishing, Inc., 1997), pages 18, 21-23, 212, 214, 219-221, 223, 228-229. ISBN 0-87983-706-3
 Cooper, M.D., M.P.H., Kenneth H., Advanced Nutritional Therapies (Nashville: 1996, Thomas Nelson, Inc. Publishers), pages 87-88, 93, 94. ISBN 0-7852-7302-6
 Balch, M.D., James F., and Balch, C.N.C, Phyllis A., Prescription for Nutritional Healing, Second Edition (Garden City Park, NY: 1997, Avery Publishing Group), pages 35-36. ISBN 0-89529-727-2
 Colgan, Ph.D., Michael, Optimum Sports Nutrition: Your Competitive Edge (Ronkonkoma NY: 1993, Advanced Research Press), pages 268, 330, 333-334. ISBN 0-964840-5-9
 Barbul, A. et al., Surgery, vol. 90, p. 244, 1981, as cited in Quillin, Ph.D., R.D., Patrick, Healing Nutrients (New York: 1989, Vintage), page 164. ISBN 0-679-72187-8
 Pearson, Durk and Shaw, Sandy, Life Extension: A Practical Scientific Approach (New York: 1980, Warner Books), pages 289, 612. ISBN 0-446-38735-5
 Lamm, M.D., Steven and Couzens, Gerald Secor, Younger at Last: The New World of Vitality Medicine (New York: 1997, Simon & Schuster), pages 62-64. ISBN 0-684-83438-3
 Klatz, D.O., Ronald with Kahn, Carol, Grow Young with HGH (New York: 1997, HarperCollins Publishers, Inc.), pages 200, 201, 206, 304. ISBN 0-06-018682-8
 Hendler, M.D., Ph.D., Sheldon Saul, The Doctor's Vitamin and Mineral Encyclopedia (New York: 1990, Fireside), pages 209-215. ISBN 0-671-66784-X
 Mindell, Ph.D., Earl, Earl Mindell's Anti-Aging Bible (New York: 1996, Fireside), pages 23-24. ISBN 0-684-81106-5
 Murray, N.D., Michael T. and Pizzorno, N.D., Joseph, Encyclopedia of Natural Medicine (Rocklin, California: 1991, Prima Publishing), page 359. ISBN 0-55958-091-7
 Le Vert, Suzanne, HGH: The Promise of Eternal Youth (New York: 1997, Avon Books), page 169. ISBN 0-380-78885-3
 Quillin, Ph.D., R.D., Patrick, Healing Nutrients (New York: 1989, Vintage), pages 274, 368. ISBN 0-679-72187-8
 DiPasqual, M.D., Mauro G., Body Building Supplement Review (no city listed: 1995, Optimum Training Systems), page 37.
 Visek, W.J., Journal of Nutrition, vol. 116, p. 36, Jan. 1986, as cited in Quillin, Ph.D., R.D., Patrick, Healing Nutrients (New York: 1989, Vintage), page 165. ISBN 0-679-72187-8
 Dean, M.D., Ward and Morgenthaler, John, Smart Drugs & Nutrients (Menlo Park: 1990, Health Freedom Publications), page 68. ISBN 0-9627418-9-2
 Whitaker, M.D., Julian, Dr. Whitaker's Guide to Natural Healing (Rocklin, California: Prima Publishing, 1996), page 269. ISBN 1-55958-495-5