The results of a meta-analysis suggested that dietary folate may have preventive effects against breast cancer risk, especially among those with a higher alcohol consumption.
Increased consumption of alcoholic beverages is a risk factor for breast cancer in women. Some of the epidemiological studies that have investigated the association between alcohol intake and breast cancer risk, have found that the intake of the B-vitamin „folate“ can be a confounding factor in this relationship. Folate plays an important role in the DNA synthesis which is essential for maintaining the DNA integrity. A folate deficiency may disrupt the gene integrity and the DNA repair process which in turn, may alter critical tumour suppressor genes. Several studies have suggested that high folate intake may reduce the risk of breast cancer, others have not found such a relationship.
Due to these inconsistent results, Chinese researchers carried out a systematic review and meta-analysis to assess available epidemiological studies and determine whether any association between folate intake, circulating folate level and the overall risk of breast cancer exists. Sixteen eligible prospective studies (with 744 068 participants and 26 205 breast cancer patients) and 26 case-control studies (with 16 826 cases and 21 820 controls) were identified. The analysis of the case-control-studies suggested a significant negative correlation while the prospective studies indicated a U-shaped relationship, with daily dietary folate intakes between 153 and 400 μg showing a significantly lower risk compared to those below and above these intakes. Noteworthy is the reduced breast cancer risk for women with a higher alcohol consumption and an increased dietary folate intake, but not for those with lower alcohol intake.
Chen P, Li C, Li X, et al. Higher dietary folate intake reduces the breast cancer risk: a systematic review and meta-analysis. Br J Cancer. 2014 Mar 25. doi: 10.1038/bjc.2014.155. [Epub ahead of print]
For more information about this article, read the scientific abstract here.