A diet rich in vitamin C could cut the risk that cataracts will progress by a third, suggests research in Ophthalmology. Indeed, diet and lifestyle may be more influential than genetics in determining the development and severity of cataracts.
The study included 151 monozygotic and 173 dizygotic white, female twins aged, at baseline, 50.1 to 83.1 years (mean 62.3 years) from the TwinsUK study. Researchers followed patients for an average of 9.4 years. Based on statistical modelling, genes accounted for 35 per cent of the risk of progression and “individual environmental factors”, such as diet, for 65 per cent.
Seven micronutrients (potassium, magnesium, manganese, phosphorus, vitamins C and E, and folate) were associated significantly with central nuclear dip score, which indicates severity of lens opacification. After allowing for inter-relationships between nutrients, vitamin C and manganese remained associated with cataracts at baseline. Vitamin C was also associated with cataract progression.
Vitamin C-rich diet cuts cataract risk
Comparing the highest and lowest tertiles, vitamin C intake was associated with a 19 per cent lower risk of cataract at baseline and a 33 per cent reduction in the risk of cataract progression. For the middle tertile, reductions were 11 and 25 per cent respectively.
The middle and highest tertile of manganese intake was associated with a 24 and 20 per cent risk reduction of cataract at baseline compared to the lowest tertile. The risk of cataract at baseline was 18 per cent lower in the highest and middle tertile of micronutrient supplement use.
“The most important finding was that vitamin C intake from food seemed to protect against cataract progression,” says study author Christopher Hammond, professor of ophthalmology at King’s College London. “While we cannot totally avoid developing cataracts, we may be able to delay their onset and keep them from worsening significantly by eating a diet rich in vitamin C.”