Source Biosyntrx:

N-Acetyl-Cysteine (NAC) is the acetylated form of the amino acid L-Cysteine. It has been suggested in a large number of published scientific studies to rapidly metabolize to intracellular glutathione, the mother-of-all-antioxidants found inside every cell in the body, including the eye.

Food is not a significant source of N-acetyl-cysteine.  Dietary cysteine is found in high-protein foods, including egg yolks and poultry.


Glutathione is produced in the liver from three amino acids, cysteine, glutamic acid and glyceine. Very small amounts are found naturally in fruits, vegetables and meats, but absorption rates of both natural and supplemental glutathione seem to remain fairly low.

A review published in the August 2009 American Family Physician suggests that NAC supplementation is linked to prevention of chronic obstructive pulmonary disease exacerbation, prevention of kidney damage during imaging procedures, attenuation of illness from the influenza virus, if started before infection, and eradication of Helicobactoer pylori and hearing loss in patients on renal dialysis.

The long-proven ability of NAC to increase glutathione production is also particularly important during flu and cold season:

1. Evidence suggests that glutathione helps the body inhibit viral replication

2. Adequate glutathione levels help to prevent unwanted mucus buildup in the lungs

3. Double-masked research suggests that NAC supplementation lowers the risk of chronic bronchitis recurrences

A recent study looked at NAC glutathione and markers of inflammation and oxidative stress in an early model of diabetic retinopathy. The results show that plasma markers of oxidative stress and inflammation are minimized with NAC treatment.  This suggests that early supplemental therapies can reduce free radical damage in the diabetic eye.

NAC and Alzheimer’s

A study published in an August 2009 peer-reviewed journal on rats treated with aluminum to induce cognitive dysfunction similar to that of Alzheimer’s disease had promising results for those at genetic and other increased risk of developing Alzheimer’s disease. The study rats pre-treated with NAC maintained significantly improved memory retention during tasks, decreases oxidative damage and reduced acetyl-cholinesterase activity, which is the enzyme that breaks down the neurotransmitter acetylcholine that plays a key role in memory, learning and many other brain functions.  The NAC untreated rats did not fair well at all.

NAC and Tylenol

NAC has been used in hospitals for years to treat liver damage caused by, mostly excessive, Tylenol (acetaminophen) intake. Even though Tylenol controls about 35% of the pain killer market in North America; acetaminophen overdose is responsible for more emergency room visits than any other medicine on the OTC market.

Has anyone ever though of including NAC in Tylenol? Don’t jump on that one too fast!

NAC is more efficacious if taken as part of a full-spectrum vitamin/mineral/antioxidant multiple. It chelates heavy metals, including mercury, and it also increases the excretion of zinc, copper and other minerals if excessvie amounts are taken over an extended period of time. NAC should also always be taken with a host of vitamin and plant-based antioxidants to regenerate active glutathione and keep it from becoming a pro-oxidant.

Again, we come back to the importance of micronutrient synergy.

The Biosyntrx full-spectrum multiples include N-acetyl-cysteine: Macula Complete includes 200 mg of NAC in each recommended daily dose. Oculair includes 100 mg of NAC in each recommended daily dose.

Ellen Troyer, MT MA

Biosyntrx Chief Research Officer