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N-cetylcysteine combats alzheimer's

Storm of the eye

It’s not exactly a household word, although more and more we’re seeing evidence that it probably deserves to be one.

NAC, N-acetylcysteine, is an invaluable amino acid that enhances the production of glutathione, one of the body’s most powerful antioxidant enzymes. I first told you about NAC late last year in an e-Alert titled “Three alternatives you can use now to prevent Alzheimer’s” (11/27/01). And as the title of that November e-Alert indicates, supplements of NAC may be an important tool in combating Alzheimer’s disease, as well as a host of other health problems from influenza to heart disease.

But I’m getting a little ahead of myself here. Since last November, I’ve been on the lookout for further research and information about NAC, and just this week I found a study that promises a new and effective use for NAC in treating a very troubling eye disorder.

The eyes of Istanbul

Chronic posterior blepharitis is a fairly common inflammation of the inner eyelid caused by an abnormality in the glands that manufacture tears. A burning sensation in the eye is a typical symptom, accompanied by itching, as well as excessive dryness or sometimes just the opposite: excessive tearing. This is an uncomfortable condition that’s often difficult to treat. Standard therapy for blepharitis typically includes a round of antibiotics, sometimes in conjunction with a topical steroid. Eye drops, or “artificial tears,” and warm compresses are used for relief of symptoms.

Exactly what causes blepharitis is not known. One theory is that oxidation damage to the meibomian glands (that help create tears) may corrupt the molecules necessary to manufacture the oily layer of tear film over the surface of the eye. This was the theory recently tested by scientists in the Ophthalmology department at Okmeydani Training Hospital in Istanbul, Turkey.

The Istanbul team studied a group of 40 subjects suffering from chronic posterior blepharitis. Half of the group received standard treatments similar to those I described above, while the other half received the same treatments, supplemented with N-acetylcysteine. This group received 100 mg of NAC orally, three times each day.

After 8 weeks of treatments, the researchers found that the members of the group receiving NAC supplements showed a significantly greater improvement in the structure of their tear film, as well as a greater reduction of blepharitis symptoms. These are very encouraging results, but because of the small size and brief duration of this study, more extensive research is called for. And I expect that there’s a good chance that it’s already underway, because, long before this test was conducted, NAC was already known to be a highly beneficial supplement.

Immune system multi-tasker

Previous studies have shown that patients with ailments associated with a breakdown in the immune system are often deficient in their levels of glutathione. As I mentioned above, NAC stimulates the production of glutathione. In this capacity, NAC has been used for many years to treat chronic respiratory ailments with its ability to break up and dissolve the mucus that contributes to pneumonia, bronchitis, asthma and sinusitis.

Beyond the respiratory tract, researchers believe that further studies may show NAC to be a versatile supplement for an impressive range of diseases. For instance, in addition to blepharitis, NAC could provide other preventative benefits for vision health. Because both the macula and the lens of the eye have been shown to respond favorably to a boost in antioxidant activity, it’s theorized that NAC may eventually be used to help prevent macular degeneration and cataracts.

The ability to stimulate strong antioxidant activity is also the key to other possible benefits of NAC. Studies have already shown that NAC appears to significantly lower homocysteine levels. Add to that the antioxidant effect in reducing plaque that can clog arteries, and it’s clear why NAC is regarded as a potentially useful tool in fighting heart disease and preventing strokes and heart attacks.

The antioxidant express

I’ve already mentioned the November 2001 e-Alert in which I told you about a study of patients in the early stages of Alzheimer’s disease who showed marked improvements in cognitive functions after beginning a regimen of NAC supplements. Again, the antioxidant effect is the most likely explanation for this success. Currently, other studies are being conducted to explore the effects of NAC on other central nervous system diseases such as multiple sclerosis and Parkinson’s disease.

While the use of NAC on all of these chronic conditions is very promising, there’s no need to wait until you have an immune system emergency to start taking NAC supplements. Your body’s glutathione can sometimes be depleted by injuries or strenuous activity. Fortunately, NAC is widely available in health food stores and from supplement suppliers. The NAC dosage in the blepharitis study was 300 mg per day – only half the amount typically used in the treatment of bronchitis. But it would be wise to consult with your health care provider before taking a dosage that high. Some of the bronchitis studies report side effects of dizziness, headaches and intestinal symptoms among about 20% of participants who took 600 mg of NAC per day.
To Your Good Health,

Jenny Thompson
Health Sciences Institute



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