Nutritional Guide

Why you need it?

Lysine is one of the essential amino acids. It is found highest in muscles with only glutamic acid and aspartic acid being higher. Lysine is degraded to acetyl CoA, a critical intermediate in the Kreb cycle. Enzymes involved with acetyl CoA have been found in decreasing order in the liver, kidneys, heart, adrenal glands, thymus gland, brain and skin. Lysine is the precursor to carnitine and citrulline. Minor amounts of lysine can be made into pipecolic acid, a neurotransmitter in the brain, and it works with the help of niacin. Arginine and ornithine are antagonistic to lysine and if given in large amounts can lead to a deficiency of lysine.

There are some inborn errors in metabolism which can lead to an elevation of lysine. High amounts of lysine can result in mental retardation along with a host of different physical abnormalities including delayed sex development, facial bone abnormalities, enlarged liver and obesity. Lysine is metabolized with the help of vitamins B-2 and B-3.

Deficiency Symptoms:

• Certain vegetarian foods can be found to be deficient in lysine. Refined grains, corn, sunflower seeds, peanuts, and vegetables are generally low in lysine.
• In vegetarian diets legumes are used to supply the needed lysine.
• Deficiency symptoms usually show a decreased immune function as well as decreased growth.
• Special note: Lysine is involved in a reaction in foods called Caramelization. This reaction is also called the Maillard Reaction or Browning Reaction. It takes place in foods such as pastries, doughnuts, cookies, puffed and flaked cereals which contain lysine and simple sugars. When, during preparation, these foods are heated, a sugar hooks onto the lysine moiety of the protein chain. The body is unable to hydrolyse the protein chain that contains this caramelized lysine molecule. Absorption of this peptide can trigger immune responses or allergies.
• In addition, if a person already has borderline lysine levels, these foods can cause a deficiency in lysine. In fact, a study done in the '70's by Dr. Constance Kies of the University of Nebraska and Dr. William Caster of the University of Georgia examined 38 cereals on the growth of rats. The cereal was their sole source of nutrition. 20 of the cereals failed to keep the rats alive, while another 12 provided little or no growth. The only cereals that did well were fortified with soy protein which made up for the deficiency of lysine that occurred because of the Maillard reaction. Others, such as wheat germ, which do not have any sugars, did not cause a lysine deficiency. There may also be a connection with lysine deficiency and kidney stones (calcium oxalate) as well.

Good Food Sources:

Wheat germ, meat, eggs, fish, poultry, cheese, lima beans, shrimp, mung bean sprouts, cottage cheese, yeast.

Precautions

GRAS - Generally recognized as safe. No adverse reactions, side effects or overdose symptoms expected when taken within the recommended amounts.

In mice and chicks high intakes of lysine can cause increased cholesterol levels. In humans lysine has very little toxicity, even at high doses. Doses up to 8 g q.d. seem to be innocuous.

1.9 gm/kg IV given to rats (140 g in man equivalent dose) increase kidney toxicity to aminoglycoside antibiotics. In the absence of antibiotics no toxic effects have been noted.

The information provided on this site is for educational purposes only. Neither the information provided nor products supplied or offered should be construed to be in any way substitutes for medical attention or prescribed medication. Consult with your healthcare professional before taking any supplements or herbal remedies if you are suffering from an undiagnosed illness or if you are on prescribed medication.

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