Research paper
Antioxidant vitamin supplementation for preventing and slowing the progression of age-related cataract.
Study answer
What this study found
No evidence that antioxidant vitamins prevent or slow the incidence, progression, or cataract extraction in age-related cataract. Pooled results show no significant effect for beta-carotene (RR 0.99, 95% CI 0.91–1.08), vitamin C (RR 1.02, 95% CI 0.91–1.14) or vitamin E (RR 0.97, 95% CI 0.91–1.04) on incidence; for cataract extraction, no significant benefit for any vitamin or combination (e.g., vitamin E pooled RR 0.97, 95% CI 0.91–1.04). Adverse effects included hypercarotenodermia in 7–16% of beta-carotene users and epistaxis (~6% with vitamin E in WHS 2004/8). Given lack of benefit and…
- Study & population
- Randomized controlled trials with at least one year of follow-up; adults aged 35 years or older; sex distribution varied (some male-only, one female-only, others mixed); trials conducted in Australia, Finland, India, Italy, the United Kingdom and the United States.
- Intervention
- High-dose antioxidant regimens tested across nine randomized trials included beta-carotene, vitamin C and vitamin E, alone or in combination.
- Key limitation
- Heterogeneity in regimens, endpoints and populations; follow-up duration varied; some trials had incomplete outcome data or masking limitations; most studies conducted in developed countries with older, predominantly healthy populations; several regimens used doses well above RDAs; progression and some safety…
View source
Open PDFOriginal abstract
BACKGROUND Age-related cataract is a major cause of visual impairment in the elderly. Oxidative stress has been implicated in its formation and progression. Antioxidant vitamin supplementation has been investigated in this context. OBJECTIVES To asse…