Folic acid — vitamin and panacea or genetic time bomb?


We live in a health-conscious age — many of us supplement our diet with essential micronutrients through the discretionary use of multivitamin pills or judicious selection of foods that have a health benefit beyond that conferred by the nutrient content alone — the so-called 'functional foods'. Indeed, the citizens of some nations have little choice, with a mandatory fortification policy in place for certain vitamins. But do we ever stop to consider the consequences of an increased exposure to micronutrients? We examine this issue in relation to the B-group vitamin folic acid, and ask whether supplementation with this vitamin could introduce a strong genetic selection pressure — one that has the side effect of increasing the prevalence of some of the most significant, human life-threatening diseases. Are we affecting our genetics — is this a case of human evolution in progress by altering our diet?

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Figure 1: The putative cellular mechanism for genetic selection that is based on folate gene variant and dietary folate.
Figure 2: Cellular effect of excess synthetic folate.


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We acknowledge the support that was provided by the British Heart Foundation. Z.Y. was a British Heart Foundation Ph.D. scholar, and this work was carried out at the School of Medicine, University of Leeds, United Kingdom and the School of Applied Sciences, University of Newcastle, Australia.

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Gene flow between differentiated populations.


(HPLC). A rapid variant of column chromatography used for high-resolution separation of molecules of low-to-moderate molecular weight.


The affinity of enzymes for a substrate.


Also known as toxaemia, it is a condition that can occur in a woman in the second half of her pregnancy that causes high blood pressure, protein in the urine, blood changes and other problems such as low birth weight.


A condition that occurs at birth in which part of the spinal cord protrudes through a small indentation in the spinal column resulting in partial to total loss of voluntary movement in the lower body.


A factor that causes malformation of an embryo.

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Lucock, M., Yates, Z. Folic acid — vitamin and panacea or genetic time bomb?. Nat Rev Genet 6, 235–240 (2005).

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