Recommended dietary allowances (RDAs) for genomic stability.

Diet as a key factor in determining genomic stability is more important than previously imagined because we now know it impacts on all relevant pathways, i.e. exposure to dietary carcinogens, activation/detoxification of carcinogens, DNA repair, DNA synthesis and apoptosis. Current recommended dietary allowances for vitamins and minerals are based largely on the prevention of diseases of deficiency such as scurvy in the case of Vitamin C. Because diseases of development, degenerative disease and ageing itself are partly caused by damage to DNA, it seems logical that we should focus better our attention on defining optimal requirements of key minerals and vitamins for preventing damage to both nuclear and mitochondrial DNA. To date our knowledge on optimal micronutrient levels for genomic stability is scanty and disorganised. Appropriately designed placebo, controlled trials are required to define recommended dietary allowances for genomic stability. Recently, it has been shown that above RDA intakes of folic acid and Vitamin B12 are required to reduce the micronucleus index in humans by 25%. In the future, clinical trials with a defined wider array of complementary DNA damage end-points would be necessary. That there is a need for an international collaborative group to establish RDAs for genomic stability is self-evident and this paper is a call for such a process to begin.