L-Cysteine Amino Acid Supplements & Roles in the Body

L-Cysteine is an amino acid that is important for a number of different functions in the body.

Supplementing with Cysteine or its derivative N-acetyl cysteine may help to increase intracellular glutathione availability, which works as a potent antioxidant.

Cysteine is able to be synthesized in the liver via methionine, and it is available in certain foods. It is a semi-essential, proteinogenic amino acid that is normally made by the body in adequate amounts.

However, under certain circumstances it becomes necessary to supplement through the diet. There is also evidence that supra-nutritional quantities (intake above the normal dietary consumption) of this amino acid can promote health in certain ways.

L-Cysteine’s specific amino acid structure and sulphur content make it critical for a number of biological functions. These include building protein chains, metabolizing fatty acids and stimulating natural killer cell production in the immune system.

It is also necessary for the development of healthy skin, hair and nails and is a component in myelin production. Myelin sheaths insulate our neurons and the nerves that send signals between them. Degradation of myelin sheaths in the brain has been linked to cognitive dysfunctions and poor neurotransmission.

Cysteine amino acid deficiencies are not common in the West, but can be a problem for vegans and vegetarians. Chronically low levels may lead to early aging, a higher risk of infections, cancer, degenerative diseases like Parkinson’s and numerous other health maladies.

Cysteine

Amino Acid

Skin

Hair

Anti- Aging

How It Works:

• Promotes healthy skin, hair & nails
• Aids in the formation of collagen
• Supports protein structure for anti-aging

Dosage:

Between 200 - 500 mg per day

Safety:

Generally Well Tolerated

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L-Cysteine Amino Acid Review

Amino acids are organic compounds that form the building blocks of proteins and play a number of different roles throughout the body.

These compounds contain amine (-NH2) and carboxylic acid (-COOH) groups in their molecules.

There are over 500 amino acids that have been identified and they make up one of the largest components of the human body. Amino acids are categories as essential, semi-essential or non-essential depending on whether our bodies can synthesize them.

Essential aminos cannot be produced in the body and we must derive them from our diet or from supplements. Non-essential aminos can be produced in the body and supplementation is usually not necessary to correct a deficiency.

Semi-essential aminos can be produced in the body, but sometimes must be supplemented in order to attain adequate levels. L-Cysteine is an example of a semi-essential amino acid.

N-Acetyl Cysteine Supplements

Some of the cysteine we consume from foods we eat will be converted into N-Acetyl Cysteine in the body. This is an acetylated derivative that cannot be derived from foods and must be either synthesized endogenously or consumed through supplements.

N-Acetyl Cysteine is very important because we need it to make glutathione – one of the strongest anti-oxidants present in the body.

When looking for L-Cysteine amino acid supplements online, you will likely see that N-Acetyl Cysteine is much more common. This compound is considered to be more potent and increases glutathione levels to a greater degree. For instance, it is used to combat the effects of acute acetaminophen toxicity and to protect the liver when exposed to other forms of damaging compounds.

NAC is sold as a dietary supplement in health food stores, but it has also been approved as a prescription drug by the FDA in the treatment of some conditions and diseases.

Best Sources of L-Cysteine

There are several food sources that are rich in cysteine and other amino acids. However, this amino acid is easily destroyed by cooking and other preparation processes. Cysteine is water soluble and may be leached out via boiling. High heat cooking and mechanical manipulation of foodstuffs also degrade cysteine significantly.

Foods that are high in cysteine include:

• Lean cuts of meat;
• Shellfish and certain other seafoods;
• Soy products;
• Dairy products;
• Wheat germ, raw oats and certain other grains;
• Green leafy vegetables.

Although there are plenty of foods that contain cysteine, they do not elevate intracellular glutathione synthesis significantly. Even the leanest cuts of meats contain only about 2% cysteine. It is even less prevalent in other food sources.

This means that elevating cysteine levels via dietary choices alone is often not a realistic option. It would require massive consumption of raw cysteine-rich foods to elevate it to desirable levels.

How to Raise L-cysteine Levels

L-cysteine supplementation is popular to improve the body’s defense from oxidative damage and to reduce the risk of liver damage.

It has become an important component of many anti-aging supplement routines and is also used by athletes.

However, getting L-cysteine into the blood is difficult because it is significantly metabolized in the digestive tract. The free cysteine that does make it into the bloodstream is sometimes oxidized there, giving off potentially toxic by-products, including hydroxyl radical agents.

Hypercysteinemia is a possibility with long-term supplementation of L-cysteine. This may cause heart troubles, kidney malfunctions and various other possible adverse effects.

Speak with your doctor about the possible benefits and side effects of cysteine amino acid supplementation as it pertains to your specific health scenario. For these reasons, it is more common to supplement with N-Acetyl Cysteine which is considered to be more bio-available and increases levels of glutathione to a greater degree.

Cysteine Benefits: Increased Glutathione

Supplementation with L-cysteine has been clinically shown to increase glutathione production, but only by small amounts. Taking NAC instead will improve the results. Elevations in glutathione levels are known to:

• Increasing the body’s antioxidant capacities. Not only is glutathione the most versatile and potent antioxidant; it also is required for other antioxidants to do their jobs effectively.
• Detoxifying various pollutants. By binding to heavy metals, carcinogens, pesticides, herbicides, steroids, antibiotics and other toxic substances, glutathione helps to clear the body of oxidizing agents.
• Accommodating the healthy production and maintenance of immune system cells. Glutathione helps to synthesize immune cells, and it serves as a cleansing antioxidant within them.
• Increasing mitochondrial energy synthesis. Glutathione keeps the mitochondria in eukaryotic cells fueled with energy. Many conditions like Type Ii diabetes and obesity are results of mitochondrial energy imbalances.
• Reducing oxidative damage. By replacing electrons lost to free radical attacks, free radical chain reactive damages are thwarted by glutathione.

Regularly using a cysteine amino acid supplement or N-Acetyl Cysteine may help to elevate glutathione levels and thereby enhance overall health in various ways. Discuss the advantages and risks of cysteine supplementation with a physician before beginning.

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