Evidence supporting the use of: N-Acetyl Carnosine
For the health condition: Cataracts
Synopsis
Source of validity: Scientific
Rating (out of 5): 2
N-Acetyl Carnosine (NAC) is used in some eye drop formulations marketed for the treatment or support of cataracts. The rationale is based on its role as an antioxidant, specifically targeting oxidative stress in the lens, which is a key contributor to cataract formation. Several small clinical trials, primarily conducted in Russia, have reported that topical NAC may slow the progression of cataracts and improve lens transparency in elderly patients. A notable study (Babizhayev et al., 2002) found statistically significant improvement in visual acuity and lens clarity in patients using 1% NAC eye drops compared to placebo. The proposed mechanism involves NAC acting as a prodrug for carnosine, delivering antioxidant activity and protecting lens proteins from glycation and oxidation.
However, the overall scientific evidence is limited and of modest quality. Most studies are small, short-term, and lack rigorous methodology by modern standards (e.g., blinding, large sample sizes, independent replication). Systematic reviews (e.g., by the Cochrane Library) have concluded that while there is some preliminary evidence, there is insufficient high-quality data to firmly recommend NAC for cataracts. Major ophthalmological associations do not currently endorse its use as a standard treatment. Therefore, while the use of N-Acetyl Carnosine for cataracts is based on some scientific studies, the evidence is not robust, and more high-quality, independent trials are needed.