Vegetable-Fruit-Soybean Dietary Pattern and Breast Cancer: A Meta-Analysis of Observational Studies

Breast cancer is one of the most common cancers among women worldwide, and several studies have investigated the association of dietary patterns and breast cancer. However, findings of studies are inconclusive. Therefore, we aimed to conduct a meta-analysis to summarize the available data regarding the association of vegetable-fruit-soybean dietary pattern and breast cancer. A systematic literature search was conducted via PubMed, Web of Science and EMBASE to identify eligible cohort studies before February 2019. A total of 12 cohort studies were included in the meta-analysis. The summary relative risks (RR) with 95% CI were calculated with a fixed-effects model. The overall RR of breast cancer for the highest versus lowest intake of vegetable-fruit-soybean dietary pattern was 0.87 (95% CI, 0.82-0.91), with little heterogeneity (p=0.73, I²=0%). There was no obvious publication bias according to funnel plot and Begg's and Egger's test. In summary, the evidence from this meta-analysis indicates that vegetable-fruit-soybean dietary pattern was inversely associated with breast cancer. However, well-designed randomized controlled trials are needed to elicit the clear effect of vegetable-fruit-soybean dietary pattern and breast cancer. Women can reduce the risks of breast cancer by eating more fruits and vegetables and soybeans, which is a constructive suggestion.