Can-C 的有效成分是 N-Acetylcarnosine（NAC）。 2004 年，俄罗斯眼科医生 Mark Babizhayev 进行了小规模试验，并认为它改善了白内障患者的视力清晰度。根据美国国家卫生研究院（NIH）官网存档的论文，作者认为「These data showed that N-acetylcarnosine is effective in the management of age-related cataract reversal and prevention both in human and in canine eyes」。
不过，迄今为止，NAC 作为治疗白内障的药物是否有效，并没有得到 FDA 的认可和批准。 2005 年，FDA 致信给一家叫做 Nucura Pharmaceuticals, Inc.（BioNational Pharmaceuticals）的公司，指出其 NU-EYES™ 眼药水宣称包含 N-Acetylcarnosine，用于治疗包括白内障在内的眼科疾病，没有足够的证据、未经 FDA 批准，必须立刻纠正。
Being a non-surgical oriented person , I began researching non-surgical cataract treatments…although I was very skeptical that anything but surgery would correct the cataracts. I came across Can-C and read the research by the original Russian scientist and ordered a Five Month supply. After just 1-week I noticed more vivid colors and both cataracts appeared to be smaller. Fast forward to almost 3-months usage … and I’m blown-away with the fantastic results. Not only can I read fine print … both cataracts have shrunk in size by about 80%…truly unbelievable!