Q: What is epigenetics? My cousin mentioned that she uses supplements to "improve her body's methylation process," and that this is related to epigenetics. I am interested in learning more and how I might benefit from this as well.
- Esther J., Hartford, Conn.
A: Epigenetics is the study of genetic variations caused by external factors, as opposed to changes in DNA sequences that happen as genes are passed down from one generation to the next. One of the most effective ways to change gene expression is through diet.
After you eat, the nutrients extracted from your food enter certain metabolic pathways in your body, where they are broken down into "usable" molecules. One of these metabolic pathways is responsible for manufacturing methyl groups, which play a vital role in epigenetics.
SAM-e (S-Adenosyl methionine) and B vitamins, particularly folate, are the main components of this methyl-making pathway. For this reason, diets high in these nutrients can rapidly alter gene expression, especially during early development when a person's epigenome is being formed.
Your mother's diet during pregnancy and your diet as an infant both affect your epigenome. Animal studies have shown that diets lacking in choline (part of the B complex) or folate before or just after birth cause regions of the genome to be under-methylated for life. A methyl-deficient diet can also lead to a decrease in DNA methylation in adults, but this is reversible when methyl-rich nutrients are added back into the diet.
The Key to Healthy Genes
Thanks to a landmark study in 2003 (the Human Genome Project), scientists have discovered that the MTHFR gene-which contributes to health and well-being in multiple ways-is defective in as much as 60 percent of the population, with Hispanic populations at particular risk. When it's working right, the MTHFR gene sets off a multi-step process called methylation. Proper methylation is essential for binding and eliminating toxins and heavy metals. Here's how it works:
The MTHFR enzyme (produced by the MTHFR gene) breaks down folate into more-useful 5-methyltetrahydrofolat (MTHF).
MTHF helps convert homocysteine into methionine, an amino acid used to make proteins, improve the body's utilization of antioxidants, and help the liver process fats. Methionine also helps convert the strong estrogen, estradiol (E2), into a safe, breast-health-promoting form of estrogen, estriol (E3).
Methionine is converted in the liver to SAM-e, which supports immune function; helps produce and excrete serotonin, dopamine, and melatonin; and is involved in the growth, repair, and maintenance of all cells.
So, what happens when you have a defective (mutated) MTHFR gene? For starters, your body won't break down toxins or heavy metals well, and you may also have too much iron, copper, lead, or mercury in your system. Beyond that, your risk for numerous conditions increases, including cancer, arteriosclerosis, fatty liver disease, anemia, inflammation, depression, stroke, irritable bowel syndrome, miscarriages, migraines, chemical sensitivities, and dementia. According to a 2006 issue of the journal Molecular Psychiatry, "Schizophrenia-like syndromes, bipolar disorder, Parkinson's disease, Alzheimer's disease, and vascular dementia have all been associated with one or more mutations of the MTHFR gene."
FOLATE VS. FOLIC ACID
What's the difference between folate and folic acid? Folate, or vitamin B9, refers to a group of water-soluble B vitamins. It's the naturally occurring type found in meat and dark leafy greens (such as Swiss chard, pictured). Supplements labeled as folate are made with the natural, easier-to-absorb form of the vitamin. Folic acid is the synthetic form used in many supplements.
You can't change a defective gene. But you can help it perform its job better and minimize problems. Here are a few steps to help improve your body's methylation process and thereby enhance gene function:
Get the best Bs. People with a mutated MTHFR gene have difficulty converting the inactive form of folate (folic acid) and vitamin B12 (cyanocobalamin). To get around this, use supplements containing the active forms: 5-MTHF folate and methylcobalamin B12.
Use methylated vitamin B6. Vitamin B6 can also be affected by a MTHFR genetic variation. Use pyridoxal 5 phosphate (P-5-P) instead of pyridoxine.
Eat more folate-rich foods. Meat an d dark leafy greens contain the active form of folate.
Don't forget gut health. According to Ben Lynch, ND, "repairing the digestive system...should be one of the first steps in correcting methylation deficiency."
Reduce exposure to toxins. Green your household cleaning supplies and don't buy plastic.
TESTING FOR MTHFR MUTATIONS
You can get your entire genome tested through 23andme.com, and this includes testing for MTHFR mutations. Or you can get a blood test from a standard lab, which is twice as expensive as 23andme. The following websites can help you interpret your results at no cost:
Genetic Genie (geneticgenie.org): evaluates your methylation genetics from the 23andme.com raw data. LiveWello (livewello.com): provides information based on your 23andme results, including links for more about each gene's potential problem. NutraHacker (nutrahacker.com): specifies which supplements to take and which to avoid, all based on your mutations.