AIM:To examine relation between dietary carbohydrate and fat intake and the risk of age-related cataract(ARC) in middle-aged and elderly men.METHODS:A hospital-based case control study was conducted.Cases(n=360) were patients with cataract 45-85 years old,and controls(n=360) were patients who had been admitted to the same hospital for diseases not related with cataract.Cases and controls were matched with 1:1.All subjects were interviewed using a structured interviewer-administrated questionnaire that included information on socio-demographic characteristics,lifestyle habits and detailed medical history,simultaneously,the dietary intakes of nutrients were collected via a valid semi-quantitative food frequency questionnaire(FFQ).The odds ratios(OR) and 95% confidence intervals(CI) of ARC were estimated using multiple logistic regression models.RESULTS:After adjusting for multiple potential confounders,higher dietary intake of carbohydrate was associated with an increased risk of ARC.Compared to controls in the lowest quartile,the OR for cases in the highest quartile of intake was 2.161(95% CI:1.107-5.016,P<0.001).Similarly,there was a positive association between intake of polyunsaturated fatty acids and ARC.Participants in the highest quartile of polyunsaturated fatty acids intake had approximately three times the risk of ARC as did those in the lowest quartile(OR=2.989,95% CI:1.764-5.062,P <0.001).Dietary total fat intake was not associated with ARC(P=0.778).CONCLUSION:High carbohydrate and polyunsaturated fatty acid intake may increase the odds of ARC,and a healthy well-balanced diet can be used to protect ARC.