Methyl donors are chemicals that can donate a methyl group which is made up of one carbon atom and three hydrogen atoms. Methyl groups on DNA signal the genes to remain unactivated, to stay in an off position. Removing the methyl groups can signal the gene to become active. A gene that has few methyl groups atttached may be more easily activated than normally.
This excerpt includes methyl donors and at least one methyl remove-er (BPA).
“Nutritional components that may influence the methylation of epigenetically susceptible loci include folic acid, vitamin B6 and 12, selenium, choline and betaine, methionine, soy genistein, bisphenol A, tocopherols, diallyl disulfide in garlic, and tea polyphenols ”  *tocopherols are the vitamin E group.
Bisphenol A is not a natural component of food as I understand nutrition but BPA may be part of the plastic lining of cans and other food packages such as plastic drink bottles. It is also found on the slick coating of some types of register receipts. BPA may cause hypomethylation of DNA, fewer methyl groups on the DNA may cause activation of genes.
Bisphenyl A can act similarly to the hormone estrogen. Soy genistein is a phytoestrogen that may help block harmful effects of the estrogen mimetics. Other methyl donors that may help block the effects of BPA are the B vitamins folic acid, vitamin B6 and B12 and choline and betaine.
Avoiding the supplement forms and eating more food sources of Folate and methyl B12 may be more beneficial for people with defects in the methylation cycle.(MTHFR is one example). Taking the unmethylated supplement forms may interfere with the smaller quantities of bioactive folate and B12 that might be found in natural sources.
Adequate B vitamins prenatally may also help protect against DNA changes in the infant.
Folate or Folic Acid:
Folate is the form of the vitamin found in food and it is more bioactive than Folic acid. Folic acid is the form that is commonly available as a supplement and in fortified foods however it requires adequate supplies of vitamin B12 to be available in order to be converted into a more usable form. A genetic difference may exist in some individuals that prevent the body from being able to convert the inactive Folic acid form into Folate, the methylated bioactive form of the vitamin.
Food Sources of Folate, the bioactive natural form, include: most beans and peanuts, black eyed peas, green peas, grains, asparagus, most dark green vegetables, orange juice, citrus fruits. Fortified cereal and rice are good sources of folic acid, the supplemental form.
Food Sources of Vitamin B12 include: shellfish, fish, meat, poultry, eggs, milk, cheese, dairy products, Nutritional or Brewer’s yeast. Vegetarians who don’t eat dairy, eggs, fish or other meat products may need a supplement or nutritional yeast, a vegan food source of vitamin B12.
Injections of B12 may be needed for better absorption of the nutrient for some individuals with stomach problems. Adequate stomach acid and a cofactor are required for normal absorption of vitamin B12. A genetic difference may be a problem for some people causing them to need the methylated active form of B12 rather than being able to benefit from the more commonly available unmethylated supplement.
Food Sources of Vitamin B6 include: fortified cereal, barley, buckwheat, avocados, baked potato with the skin, beef, poultry, salmon, bananas, green leafy vegetables, beans, nuts, sunflower seeds.
Choline and Betaine:
Choline is also a water soluble essential nutrient that is frequently grouped with the rest of the B vitamins. Choline is found throughout the body but is particularly important within the brain. Betaine is a metabolite of choline. Spinach and beets are rich in betaine. Good sources of choline include egg yolks, soy beans, beef, poultry, seafood, green leafy vegetables and cauliflower.
/Disclosure: This information is provided for educational purposes and is not intended to provide individual health guidance. Please see a health professional for individual health care purposes./
- Kyung E. Rhee, et al., Early Determinants of Obesity: Genetic, Epigenetic, and In Utero Influences, International Journal of Pediatrics, Vol. 2012
- Rebecca J. Schmidt, et. al. , “Prenatal vitamins, one-carbon metabolism gene variants, and risk for autism,” Epidemiology. 2011 Jul; 22(4): 476–485. [ncbi.nlm.nih.gov]
- “MTHFR C677T Mutation: Basic Protocol,” on February 24, 2012