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N-Acetyl Cysteine

N-acetyl cysteine (NAC) is an amino-acid derivative (small protein) with over 40 years of scientific research to back it up. NAC’s powerful health benefits derive from its ability to restore intracellular levels of glutathione (GSH), which is the body’s most powerful antioxidant.

Glutathione is a very powerful antioxidant that helps the liver to protect you against toxicity, and it is most needed by those with liver disease. The stress of chronic liver disease depletes glutathione and this is why supplementing with one of its precursors, NAC helps to protect against ongoing liver damage.

NAC is a modified form of the sulfur-containing amino acid cysteine. NAC replenishes intracellular levels of glutathione (GSH), which restores your cells’ ability to fight damage from free radicals known as reactive oxygen species.

NAC may be able to reduce a large range of chronic, degenerative problems, including liver inflammation and impaired glucose control.

Today researchers are now realizing just how vital glutathione’s actions in the body are, and how many chronic disease conditions are associated with glutathione deficiency. According to Stanford University’s Dr. Kondala R. Atkuri, “NAC has been used successfully to treat glutathione deficiency in a wide range of infections, genetic defects and metabolic disorders, including HIV infection and Chronic Obstructive Pulmonary Disease. Over two-thirds of 46 placebo-controlled clinical trials with orally administered NAC have indicated beneficial effects of NAC measured either as trial endpoints or as general measures of improvement in quality of life and well-being of the patients.”

NAC has been shown to increase blood glutathione in HIV-infected patients with low levels of glutathione due to their chronically damaged immune system.
NAC’s ability to replenish intracellular glutathione and reduce free radical damage provides significant protection against DNA damage and thus cancer development.

NAC neutralizes toxins and pollutants including heavy metals that accumulate in the liver, kidneys and fatty parts of the body.

Restoring glutathione levels with NAC supplements makes liver cells more able to protect themselves from ongoing damage caused by fatty accumulation, viral infections, drug induced damage, alcohol excess or autoimmune inflammation etc.

How can we get more glutathione in our body?

Oral glutathione supplements are available in some health food stores and pharmacies and do not require a prescription. The main problem is that glutathione is not well absorbed from the gut, as it is broken down by digestive enzymes before it has a chance to be absorbed. For this reason it is far more effective to take its precursor (building block). NAC is the most important precursor to glutathione synthesis. NAC is easily absorbed from the gut and is rapidly turned into glutathione.

Approximately 150 milligrams daily of glutathione is obtained from the average diet, mainly from fruits and vegetables. However the majority of glutathione is manufactured within the cells of the body, especially within liver cells. It is interesting to know that around 80% of the glutathione produced in the liver is transported to the blood stream to be used by the kidneys for detoxification. Thus increasing glutathione levels is good for the liver and the kidneys.

For people with very depleted levels of glutathione in their body, taking glutathione intravenously would be best, but this is impractical. The practical solution is to take NAC, the main precursor to glutathione – a component the body’s cells need to make their own glutathione.

How is NAC taken?

NAC does not require a prescription and is taken as an oral supplement in doses of 600 to1800 mg daily. NAC is taken one to three times per daily, or as recommended by your healthcare provider. NAC can be taken with or without food.

NAC is given intravenously in hospital emergency departments as a life saving treatment for acute poisoning with paracetamol (also known as acetaminophen). Overdoses with paracetamol are the number one cause of acute liver failure in the United States. Large doses of paracetamol overwhelm the body’s glutathione stores, which causes irreversible damage to liver cells. Treatment with NAC quickly restores protective levels of glutathione, thus preventing irreversible liver failure. In paracetamol (acetaminophen) overdose, NAC is administered intravenously to detoxify the drug before it destroys large numbers of liver cells and causes fatal liver failure.

With over more than 40 years of use in a wide range of medical disorders, NAC has been proven to be safe even at very high doses and for long-term treatments. Studies have demonstrated the safety of 1,800 mg per day for 142 days, and 2,800 mg per day for 3 months. The most commonly used doses range from 600-1,800 mg daily and clinical studies have found that doses of up to 2,000 mg/day are safe.

Many researchers have come to the conclusion that a deficiency of liver glutathione is one of the leading factors that allow liver disease to progress. The liver cells of people with chronic liver disease are continually overworked as they fight toxins and free radicals and it is mainly glutathione which can protect them from severe damage or cell death. Researchers proved that glutathione given in high doses intravenously to patients with severe fatty livers resulted in marked improvement in their liver blood test results.

Here are a few recently published trials:
Published in the November 2006 journal Apoptosis, one trial investigated if NAC could inhibit liver cell death in acute severe liver failure. Based on an animal model, the researchers concluded that NAC shows a liver-protective role for this type of liver failure.
Published in the January 2008 journal Liver Transplantation, a retrospective study found that children treated with NAC for acute liver failure had a better outcome than matched controls not treated with NAC.

The evidence linking glutathione depletion with a poor prognosis in those with liver disease is now clear-cut.

Cautions with NAC

There are no known contraindications to NAC. Diabetics should check with their healthcare provider regarding interference with insulin efficacy