Creatine

The enzyme GAMT (guanidinoacetate N-methyltransferase, also known as L-arginine:glycine amidinotransferase (AGAT), EC 2.1.4.1) is a mitochondrial enzyme responsible for catalyzing the first rate-limiting step of creatine biosynthesis, and is primarily expressed in the kidneys and pancreas. more...

Home
Bath & Body
Coupons
Dietary Supplements,...
Herbs, Botanicals
Nutrition Bars, Shakes
Other
Sports Supplements
Amino Acids
Creatine
Fat Burners
Other
Protein
Testosterone
Vitamins, Minerals
Hair Care
Hair Removal
Health Care
Massage
Medical, Special Needs
Nail
Natural Therapies
Oral Care
Other Health & Beauty Items
Over-the-Counter Medicine
Skin Care
Tanning Beds, Lamps
Tattoos, Body Art
Vision Care
Weight Management
Wholesale Lots

The second enzyme in the pathway (GAMT, guanidinoacetate N-methyltransferase, EC:2.1.1.2) is primarily expressed in the liver and pancreas.

Genetic deficiencies in the creatine biosynthetic pathway lead to various severe neurological defects.

Controversy

While creatine's effectiveness in the treatment of many muscular, neuromuscular, and neuro-degenerative diseases is documented, its utility as a performance-enhancing food supplement in sports has been questioned (see Creatine supplements for more information). Some have even proposed that its use as a performance enhancer should be banned. Despite this, creatine remains very popular. .

Side Effects

Short-term use of creatine in healthy individuals is generally considered safe (see Creatine supplements#Safety). Continuous intake of excessively high dosages of creatine may lead to any of several possible side effects. It has been hypothesized that consistently high doses could lead to hypertension due to increased water retention .

Creatine supplementation utilizing proper cycling and dosages, however, has not been linked with any adverse side effects beyond occasional dehydration due to increased muscular water uptake from the rest of the body.

According to the opinion statement of the European Food Safety Authorities (EFSA) published in 2004 it was concluded that "The safety and bioavailability of the requested source of creatine, creatine monohydrate in foods for particular nutritional uses, is not a matter of concern provided that there is adequate control of the purity of this source of creatine (minimum 99.95%) with respect to dicyandiamide and dihydro-1,3,5-triazine derivatives, as well as heavy metal contamination. The EFSA Panel endorses the previous opinion of the SCF that high loading doses (20 gram / day) of creatine should be avoided. Provided high purity creatine monohydrate is used in foods for particular nutritional uses, the Panel considers that the consumption of doses of up to 3g/day of supplemental creatine, similar to the daily turnover rate of creatine, is unlikely to pose any risk". Publication date of the EFSA Statement is 26/04/2006. EFSA statement

This opinion is corroborated by the fact that creatine is a natural component in mothers' milk and that creatine is absolutely necessary for brain development in the human embryo and the baby, as well as for optimal physiological functioning of the adult human body, especially the brain, nervous system, the muscles and other organs and cells of high energy expenditure, where the creatine kinase (CK) system is highly expressed and creatine levels are high. For a scientific update on CK and creatine function see the recently published book Function of CK and Creatine in Health and Disease.

Read more at Wikipedia.org