Complex sentence: Vitamin C supplementation above the RDA has been used in trials to study a potential effect on preventing and slowing the progression of age-related cataract, however no significant effects were found from the research.
Split into simpler sentences: Vitamin C supplementation above the RDA has been used in trials to study a potential effect on preventing and slowing the progression of age-related cataract. However, no significant effects were found from the research.