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Nutritional Supplement

Cysteine

Possible Deficiencies

According to several studies, blood levels of cysteine and glutathione are low in people infected with HIV.1,2,3 Cysteine has a role in the proper function of the immune system, so a deficiency of this amino acid may either contribute to, or result from, immune suppression associated with HIV.

Side Effects

No consistent adverse effects of NAC have been reported in humans. One small study found that daily amounts of 1.2 grams or more could lead to oxidative damage.4 Extremely large amounts of cysteine, the amino acid NAC is derived from, may be toxic to nerve cells in rats.5

References

1. Eck HP, Gander H, Hartmann M, et al. Low concentrations of acid-soluble thiol (cysteine) in the blood plasma of HIV-1 infected patients. Biol Chem Hoppe Seyler 1989;370:101-8.

2. Droge W, Eck HP, Mihm S. HIV-induced cysteine deficiency and T-cell dysfunction—a rationale for treatment with N-acetylcysteine. Immunol Today 1992;13:211-4.

3. Droge W. Cysteine and glutathione deficiency in AIDS patients: a rationale for the treatment with N-acetyl-cysteine. Pharmacology 1993;46:61-5 [review].

4. Kleinveld HA, Demacker PNM, Stalenhoef AFH. Failure of N-acetylcysteine to reduce low-density lipoprotein oxidizability in healthy subjects. Eur J Clin Pharmacol 1992;43:639-42.

5. Olney JW, Ho OL. Brain damage in infant mice following oral intake of glutamate, aspartate or cysteine. Nature 1970;227:609-10 [letter].

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The information presented by TraceGains is for informational purposes only. It is based on scientific studies (human, animal, or in vitro), clinical experience, or traditional usage as cited in each article. The results reported may not necessarily occur in all individuals. For many of the conditions discussed, treatment with prescription or over the counter medication is also available. Consult your doctor, practitioner, and/or pharmacist for any health problem and before using any supplements or before making any changes in prescribed medications. Information expires December 2025.