Supplements

Lysine

Lysine is an essential amino acid that is not synthesized in adequate amounts by the body, so it must be obtained from dietary sources. Lysine furnishes the structural components for the synthesis of carnitine, which promotes fatty acid synthesis within the cell. It is particularly important for proper growth. Lysine also regulates calcium absorption and plays an important role in the formation of collagen.

This amino acid aids in the production of antibodies, hormones, and enzymes, and helps to build muscle protein. It is good for those recovering from surgery and sports injuries. It also lowers high serum triglyceride levels.

Among protein sources, plants often contain insufficient sources of lysine. Lysine is the limiting amino acid of many cereals. In many areas of the world where diets are grain-based, this becomes important as a lysine deficiency can create a negative nitrogen balance and lead to kidney stones.

Lysine has the capacity for fighting cold sores and herpes viruses. Taking supplemental L-Lysine, together with vitamin C with bioflavonoids, can effectively fight and/or prevent herpes outbreaks, especially if foods containing the amino acid arginine are avoided.

Supplemental L-Lysine may also decrease acute alcohol intoxication.

Some studies have found lysine of potential benefit in treating cardiovascular disease, osteoporosis, asthma, migraines, nasal polyps, and postepisiotomy pain.

• Asthma: LAS, when administered by inhalation, has been shown to protect against histamine-induced bronchoconstriction.
• Herpes: Supplementation may improve recovery speed and suppress recurrences of infections.
• Migraine: Treatment with a combination of LAS and metoclopramide may be effective.
• Nasal polyps: Recent research suggests that LAS may prevent relapses of nasal polyps.
• Postepisiotomy pain: 125 mg/day of LC was found to reduce postepisiotomy pain in primiparous patients with moderate to severe postepisiotomy pain.

Deficiency: Lysine deficiency may be characterized by fatigue, nausea, dizziness, appetite loss, emotional agitation, decreased antibody formation, decreased immunity, slow growth, anemia, reproductive disorders, pneumonia, acidosis, and bloodshot eyes.

Sources: Generally, lysine is found in meat, particularly red meats, cheeses, poultry, sardines, nuts, eggs, and soybeans. The most concentrated sources are torula yeast, dried and salted cod, soybean protein isolate, soybean protein concentrate, Parmesan cheese, pork loin (excluding fat), dried and frozen tofu, defatted and low-fat soybean flour.

Herb Sources: Fenugreek seed, parsley, spirulina

Precautions: Lysine appears to be nontoxic. L-lysine may increase cholesterol and triglyceride levels.

Dosage Ranges and Duration of Administration: The following are the recommended dietary allowances, according to the National Research Council:

• Birth to 4 months: 103 mg/kg/day
• 5 months to 2 years: 69 mg/kg/day
• 3 to 12 years: 44 mg/kg/day
• Adults and teenagers: 12 mg/kg/day

Based on obligatory amino acid losses (including data from amino acid tracer studies), it has been suggested that adults need 30 mg/kg/day.
Nutritional doses are 1 to 3 g per day.

INTERACTIONS

No clinically significant interactions between lysine and conventional medications are known to have been reported in the literature to date.