Association of Vitamin E on the risk of ovarian cancer: A meta-analysis

Abstract

Many researches were conducted to assess the association of Vitamin E intake on the risk of ovarian cancer, with conflict results. The current meta-analysis of published observational studies aimed to investigate the effect of Vitamin E intake on ovarian cancer risk. The summary relative risks (RRs) with corresponding 95% confdence intervals (CIs) were calculated to measure the effectiveness of Vitamin E intake on ovarian cancer risk using a random-effects model. As a result, 14 studies including 4597 patients were identified. Eleven studies reported about total Vitamin E intake, eight studies about Vitamin E intake from food only and five studies about Vitamin E intake from supplement only on the risk of ovarian cancer. Overall, the summary RRs on ovarian cancer risk was 0.95 (95%CIs = 0.78-1.16) in total Vitamin E intake, 0.99 (95%CIs = 0.77-1.27) in Vitamin E intake from food only and 0.82 (95%CIs = 0.54-1.25) in Vitamin E intake from supplement only. Results in subgroup analyses by study design and geographic location were consistent with overall result. In conclusions, the findings of this meta-analysis suggested that high intake of Vitamin E from food or Vitamin E supplement had no significant effect on the risk of ovarian cancer.