Threonine

* An amino acid

Functions:

Threonine is an amino acid used in cosmetics and personal care products because of its ability to promote growth though protein balance maintenance. One of its primary functions is its assistance in creating glycine and serine, two other amino acids that are "necessary for the production of collagen, elastin, and muscle tissue," according to VitaminStuff.com. Threonine also supports connective tissues and muscles, and keeps them strong and elastic. It is considered helpful in building strong bones, tooth enamel, and is considered a wound healer. According to the Cosmetics Database, it is a fragrance ingredient, skin and hair conditioning agent, and anti-static agent. It is often seen in hair straighteners because of its protein promotion.

Threonine is produced naturally in the body, and is also found in foods like cottage cheese, poultry, fish, meat, lentils, and sesame seeds (Wikipedia).

Threonine is FDA approved.

Safety Measures/Side Effects:

Threonine is considered a low hazard ingredient by the Cosmetics Database, although the EWG does note cancer concerns, due to in vitro tests on mammalian cells show positive mutation results. It lists lesser concerns regarding brain, nervous system and respiratory effects at high doses unlike those found in topical hair and skin formulas.

Threonine can also be taken as a dietary supplement, but should be used within normal limitations, because "Exceeding the recommended doses of threonine can disrupt liver function, and cause the formation of too much urea, and consequently ammonia toxicity, in your body" (VitaminStuff.com).

Recommended Products w/ Threonine:

Philip B Botanicals Russian Amber Imperial Shampoo, Davine’s Natural Tech Hairbuilding Pak, Murad Essential C Toner, Guinot Tres Homme Longue Vie Homme, Lancaster’s Sunslim, Long Hair Lover’s Rare Hair Oil, Circadia Myo-Cyte Rx Serum, AminoGenesis Cocoon Total Body Emollient