N-acetylcarnosine, a dipeptide found in muscle and nerve cells, can help maintain protein integrity in the lens and is being studied in eye drop form for treatment of cataracts. When applied in eye drops, NAC makes its way to the interior of the eye, where it may have antioxidant effects. Oxidation of lipids in the lens of the eye is thought to contribute to cataracts. NAC may also help prevent cross-linking of proteins, another factor behind cataracts. N-acetylcarnosine has a wealth of properties which can improve the function of the aging eye.