L-Cysteine Review: Uses, Supplements and Safety Report

In this L-Cysteine review, we will discuss the uses of this amino acid, reported effects, safety and how to take this product as a dietary supplement.

Most cysteine supplements are in the form N-acetyl Cysteine (NAC). NAC is an acetylated form of the semi-essential amino acid cysteine.

While this compound can be synthesized in the body from methionine, and also found in various food sources, NAC is not found in foods and must be made from cysteine.

The best food sources for cysteine are high-protein choices like green leafy vegetables, lean meat cuts, whey protein, wheat germ, oats and ricotta cheese. Cysteine is sometimes used as a dietary supplement to improve the health and appearance of skin, hair and nails.

It has been touted as a potential treatment for hair loss and greying. Healthy individuals should not need to supplement with cysteine under normal circumstances, but taking NAC can improve liver function and help protect the body from oxidative damage.

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 Review

NAC has numerous uses as a detox supplement, an athletic performance enhancer and for increasing levels of glutathione in the body.

N-acetyl Cysteine is actually the rate-limiting factor for glutathione peroxidase production, meaning that you need this compound in order to make this powerful enzyme antioxidant.

NAC is used widely by physicians to treat angina, heart attacks, cancers, eye diseases, lung infections and various other conditions and diseases. In research trials, it has been shown to decrease fatigue, improve sperm motility and sperm count as well as improve symptoms of certain psychological disorders.

According to research reviews, Cysteine supplements may provide general health improvements via antioxidant actions; leading to enhanced immune system responses, lessened damages from ROS (reactive oxygen species) and slowing signs of the aging process. It can also help to protect the liver from damage caused by alcohol, toxins and even some drugs like Tylenol that get metabolized in the liver.

Although current clinical proof is lacking for many of the proposed health benefits of NAC supplementation, research continues to unveil promising therapeutic potentials.

Benefits of Cysteine Capsules

Many people use cysteine supplements for various conditions and diseases that are not yet supported by clinical evidence of effectiveness. For instance, 800 mg doses daily are believed to possibly ameliorate symptoms associated with AIDS and HIV. NAC supplementation is believed to delay the degradation of the immune system in these patients. User reviews of L-Cysteine attest to numerous other anecdotal benefits from this product.

N-acetylcysteine is also believed to help prevent liver damage due to chronic alcoholism. Further, it is used to provide liver and kidney protection from environmental poisons like carbon monoxide, chloroform, herbicides, pesticides, pharmaceuticals, illicit drugs, x-rays and acetaminophen (Tylenol).

Further uses for N-Acetyl Cysteine supplements include treating hay fever, cancer in the neck and/or head, fibrosing alveolitis, epilepsy, lung cancer, ear infections, kidney dialysis complications, sports injuries, chronic fatigue syndrome and influenza.

None of these therapeutic purposes for cysteine supplements have been  validated in clinical trials. Supplementing for these purposes may lead to complications and should be discussed with a doctor beforehand.

Cysteine Supplements for Bronchitis

NAC administration is an accepted treatment for the symptoms of bronchitis and some other respiratory conditions. It seems to break down mucus and promote decongestion. In one assessment of the results from 39 clinical trials addressing NAC and bronchitis, it was found that 400 mg to 600 mg daily oral doses effectively and safely treat chronic bronchitis.

NAC cysteine supplements may decrease bronchitis aggravations by as much as 50%. NAC also seems to benefit smokers of commercial tobacco products by thinning mucus and decreasing harmful bacteria that breed in the lungs.

Cysteine Supplements and Heart Health

NAC is administered in hospitals in conjunction with nitroglycerine to improve success rates for treating various heart conditions.

It improves the vasodilatory effects of nitroglycerine and is believed to ameliorate angina pains.

In one study, 11 people with unstable angina conditions were given three daily doses of 600 mg of NAC. Also, a transdermal nitroglycerin skin patch was administered.

After four months, treatment group subjects showed significantly less rates for subsequent angina symptoms, including heart attacks.

In another study, cysteine supplements were injected intravenously to decrease tissue damages in people who had heart attacks. Current studies are addressing if oral administration of a cysteine supplement will produce the same effects.

Is Cysteine Safe?

According to user reviews, there are few side effects that occur from taking L-cysteine amino acids. Using a cysteine supplement like NAC is known to be possibly safe. As NAC is produced inside the body, it is well tolerated by the body at the appropriate dosages. Although very rare, there are some side effects associated, including nausea, vomiting and stomach pains. In cases of highly excessive usage (more than 7 grams daily), death is possible.

In one study, it was reported that 19% of treatment group participants experienced side effects including headaches, dizziness, dry mouth, nausea, abdominal pain and/or vomiting. This study stands alone though. Similar data has not been published from other studies.

Although NAC is well noted for its antioxidant actions, one small trial reported that 1.2 grams administered daily seemed to increase oxidative stress. Large doses of cysteine have also been shown to induce neurotoxicity in murine subjects.

NAC or cysteine supplementation may also cause increases in zinc excretion through the urinary tract. It may be necessary to supplement zinc and/or copper when routinely using a cysteine supplement, especially in cases of long-term usage.

In most cases, there will be no side effects when taken at proper doses. Current data shows doses between 200 mg daily up to 1500 mg multiple times daily are safe. The best dosage for a given therapeutic target will depend on several variables associated with a given individual. Everyone demonstrates unique health characteristics and dosing will vary greatly between individuals.

In Review

Usine a NAC supplement may help to improve human health by protecting the liver and kidneys, working as an anti-oxidant, reducing the risk for cancer and heart disease, improving immunity and various other possibilities. If you have used this product, share your L-cysteine review and experience below. Consult with your doctor before beginning cysteine supplement usage.

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