Health Benefits And Uses Of


L-cysteine is a semi-essential amino acid with antioxidant properties that support skin health, digestion, blood sugar regulation, exercise recovery, and is particularly beneficial for those with metabolic syndrome, elderly, infants or those with malabsorption issues.


Antioxidant Support

L-cysteine Background and Benefits

L-cysteine is an amino acid that is classified as semi-essential in humans, meaning that the body biosynthesizes adequate amounts of it under normal circumstances. The biosynthesis of l-cysteine requires methionine, which supplies the sulfur needed to make this amino acid. This requirement is one of the primary reasons that sulfur is an essential human nutrient.

L-cysteine is available through many dietary sources, primarily animal protein. Eggs and dairy products also contain significant levels of l-cysteine. Vegetable sources of l-cysteine include broccoli, Brussels sprouts, garlic, granola, sprouted lentils, oats, onions and peppers. The commercial extraction of l-cysteine typically uses human hair, due to its high concentration of this amino acid. Other commercial sources include hog hair and poultry feathers. L-cysteine may also be synthesized in a process that involves fermentation by a variety of E. coli.

L-cysteine’s high reactivity makes it essential in many biochemical reactions. This amino acid is a thiol, meaning that it has a sulfhydryl group at one end of its chain. This group consists of a sulfur and hydrogen atom and is the primary reason that l-cysteine is chemically active. In particular, l-cysteine readily undergoes reduction-oxidation reactions, commonly known as redox reactions. This reactivity gives l-cysteine strong antioxidant properties, which help support cells from different types of damage.

Uses of L-Cysteine

The primary health benefits of l-cysteine derive from its antioxidant properties, which helps support the body’s natural ability to manage and regulate blood sugar levels. It also supports digestive health, manages blood sugar levels, and maintains the skin’s appearance.

Skin Health Support

L-cysteine can also help your skin to maintain a healthy appearance since it’s an essential component of the proteins that make up connective tissue.

Digestive Health Support

L-cysteine also shows promise for managing poor digestion, according to one 2009 study.

Metabolic Syndrome Support

Various studies indicate that l-cysteine may be beneficial in helping support the body’s natural ability to manage and regulate blood sugar levels. It may also be able to help support healthy inflammation management.

Exercise Recovery

Exercise increases the production of free radicals, which cause cellular damage through oxidative stress. L-cysteine supplements can help you recover from exercise more quickly by suppressing free radical production.

Signs You May Need L-Cysteine

A deficiency of l-cysteine is most likely to occur in people who are unable to biosynthesize it, such as the elderly and infants. People with malabsorption issues and metabolic syndrome may also be unable to synthesize adequate amounts of l-cysteine. An l-cysteine deficiency may result in a compromised immune system, which can cause a slow recovery from injury and ailments. Additional signs that you may need l-cysteine include brittle nails, acne and scar tissue.