Researchers at the Helmholtz Eye Institute in Moscow, Russia, have demonstrated that a unique form of carnosine—n-acetylcarnosine, abbreviated as NAC—which is now available in the form of eye drops, can slowly reverse existing cataracts and prevent new ones from forming. (Note: This is not the same thing as n-acetylcysteine, which is also sometimes abbreviated to NAC.)
NAC has shown a significant clinical success rate for patients within 3-12 months of treatment. Benefits included improved visual acuity and reduced glare sensitivity,
An alternative to surgery
Individuals with cataracts often end up with surgery. But just as any surgery is not without risk, about 2% of the 1.35 million (or approximately 27,000 individuals), just in the United States each year, develop serious complications, including retinal detachments, corneal edema, and the need for a cornea transplant. Fear and discomfort, not to mention future potential problems from an artificial lens, contribute to the overall unpleasantness that accompanies this surgery.
In a long-term study, the Russian researchers observed the changes in lens clarity over a 6 to 24 month period for 49 volunteers. The average age of the participants was 65, and all suffered from senile cataracts ranging from minimal to advanced opacification (clouding of the lens).
The patients received either a 1% solution of NAC eye drops or a placebo, as two drops twice a day in each eye. The patients were then evaluated after two months and again after six months. The tests consisted of ophthalmoscopy (glare test), stereo-cinematagraphic (slit-image) and retro-illumination (photography). A computerized digital analysis then displayed the light scattering and absorbing effects of the centers of each lens.
- 88.9% of the patients who were treated with NAC had an improvement of glare sensitivity (lowest individual score was a 27% improvement, all the way up to a 100% improvement)
- 41.5% had a significant improvement of the transmissivity of the lens
- 90% showed an improvement in visual acuity
- The patients in the placebo group exhibited little change in eye quality at 6 months and a gradual deterioration at 12 to 24 months
This study also showed that at 24 months the NAC treated group (who already had significant improvement to the quality of their eyesight), sustained these results with continued use of the NAC eye drops. There were no significant side effects noted in any cases throughout the two-year period.1
Another Russian study evaluated two groups of 49 patients (with the average age being 65), who had advanced symptoms of cataracts. After a 24 month course of treatment, the group that was treated with the eye drops had a cumulative positive change when compared with the group that did not receive the eye drops.2 How does NAC work?
The body is made up largely of proteins. As we age, proteins tend to undergo destructive changes due largely to oxidation and interactions with sugars and aldehydes. These interrelated protein modifications include oxidation, carbonylation, cross-linking, glycation, and advanced glycation end product (AGE) formation. These processes contribute to the aging process.
More specifically, cataracts are formed by the glycation of proteins. Glycation occurs when proteins react with sugars and form advanced glycation end products (AGEs). AGEs physically alter proteins, DNA, and lipids, changing their chemical properties. The result of this reaction leads to the discoloration of the eye lens to yellow and brown, which consequently results in the impairment of vision.
Studies show that carnosine is effective against all these forms of protein modification. When the NAC eye drops are administered, carnosine competes for the glycating agent on the molecule, and protects cellular structures against aldehydes. Therefore, it is believed that carnosine can slow and help to prevent proteins from cross-linking and becoming a cataract, and break existing cross-links, too.
NAC acts as an antioxidant
Once in the aqueous humor, NAC was shown to act as an antioxidant and enter the lens tissue, and to be particularly effective against potent free radicals, especially the superoxide and the hydroxyl. It is therefore presumed that the antioxidant role of L-carnosine (within the aqueous humor) is a major factor in slowing and preventing the appearance of cataracts. It is also believed that NAC may help in the treatment of eye disorders other than cataracts that are the result of oxidative stress including: glaucoma, retinal degeneration, corneal disorders, ocular inflammation, complications of diabetes mellitus, and systemic diseases.3
NAC appears to act as a universal antioxidant, both in the lipid phase of the cellular lens membranes, and in the aqueous environment. It also protects the crystalline lens from oxidative stress-induced, cross-linking damage.
NAC and nighttime glare
Another benefit users of NAC eye drops report is improved night vision. For many people, driving at night is particularly hazardous because of a phenomenon known as nighttime glare. Stoplights, streetlights and other car’s headlights can appear almost blinding to people who suffer from nighttime glare. The reason for this is light scatters when it hits the lens of the aged eye, resulting in bright streaks of light that impair vision and reduce the contrast between light and dark areas. It’s believed the NAC works like a windshield wiper to remove buildup on the lens of the aged eye resulting in a reduction in nighttime glare.
How much should you use?
NAC eye drops appear to be a unique and safe treatment for cataracts, and offer an exciting new solution to the way that cataracts are controlled. The studies used two drops in each eye twice daily continuously for a 24 month period.
But since there is no data on a “preventative” dosage there’s no way of knowing if one drop twice daily works as well as two drops twice daily. What we do know is that the maximal effect of improvement of visual acuity is obtained within the first three to five months of treatment. Then the goal is to maintain that outcome.
NAC as a preventative against cataracts
Please keep in mind that NAC is no miracle. Less than half the people studied showed dramatic improvements … although most of them experienced an improvement in their vision, and a stabilization of their cataracts. It’s quite possible that using NAC eye drops more often than twice a day is more effective, but no studies have been done to indicate that.
However, if you use NAC eye drops before you get a cataract, you may be able to prevent the cataract, and possibly a lot of other eye problems.
- As a preventative: Use one drop of NAC eye drops once daily.
- For existing cataracts: Use two drops twice daily.
- Then, after cataracts have been reduced to an acceptable level, use a maintenance dose of one drop twice daily.
Cataracts are a widespread age-related affliction. In the United States alone, Medicare estimates the annual cost at $3.5 billion for the 1.35 million cataract operations performed annually. Considering the high cost of undergoing cataract surgery, and the low cost and low risk of using NAC eye drops, it makes sense to give the “Russian Cataract Cure” a try before doing something as dramatic and invasive as surgery.
- Babizhayev MA, Deyev AI, Yermakova VN, Semiletov YA, Davydova NG, Doroshenko VS, Zhukotskii AV, Goldman IM. Efficacy of N-acetylcarnosine in the treatment of cataracts. Drugs R D 2002;3(2):87-103
- Babizhayev MA, Deyev AI, Yermakova VN, Semiletov YA, Davydova NG, Kurysheva NI, Zhukotskii AV, Goldman IM. N-Acetylcarnosine, a natural histidine-containing dipeptide, as a potent ophthalmic drug in treatment of human cataracts. Peptides 2001 Jun;22(6):979-94
- Babizhayev MA, Yermakova VN, Semiletov YA, Deyev AI. The natural histidine-containing dipeptide N-alpha-acetylcarnosine as an antioxidant for ophthalmic use. Biochemistry (Mosc) 2000 May;65(5):588-98