Folate and colorectal cancer - a review of the current evidence

Colorectal cancer is the second most common tumour in the United Kingdom. Migration studies suggest that environmental factors, particularly diet, account for the wide variation in worldwide incidence of the disease. Prospective cohort studies have shown that diets low in meat and high in vegetables decrease risk. Folate is thought to account partly for the protection conferred by high intakes of vegetables, since it plays a crucial role in maintaining genomic stability, being required in two important processes, DNA synthesis and methylation. The public health implications of existing evidence supporting a reduction in neural tube defects, ischaemic heart disease and possibly cancer fuel the nationwide folate fortification debate, while ever progressing nutritional genomic technology promises a greater understanding of the mechanisms underlying the relationship between folate and colorectal cancer risk.