Reality of MTHFR:
What is it?
The gene is responsible for making an enzyme that is important to metabolize folate (also known as folic acid or vitamin B9). It also helps cells recycle homocysteine (a chemical in the blood) into methionine (a building block for protein). There are two naturally occurring variants in this gene. They are the C677T and A1298C.
When those two variants are present, the resulting MTHFR enzyme is less active, and this can lead to decreased levels of folate and increased levels of homocysteine in the blood.
The methylenetetrahydrofolate reductase gene (MTHFR) ha had people make claims about it that it causes a variety of health problems and neurological conditions. These conditions include blood clots, cancer, migraines and many more. The myth of having one or two copies of the MTHFR variant can lead to those health problems. It is very unlikely that variants of a single gene could cause over a dozen unrelated health problems. In some ethnicities, more than 50% of people have at least one copy. Most genetic causing genetic variants are not this common.
Another myth is that people who carry an MTHFR variant should avoid foods that are fortified with folic acid. There is no evidence of this at all. Over the past 20 years, scientists have examined the association between MTHFR C677T and A1298C and 600 medical conditions. The evidence has been inconclusive or conflicting. There is no scientific evidence supporting the claims.
There is one exception. Women with two copies of the 6C77T variant appear to have a slightly increased risk of having a child with a neural tube defect like spina bifida. According to the National Institute of Child Health and Human Development, supplementing with folic acid reduces the risk of neural tube defects in all pregnant women, including those with the variant.
After a lot of research, existing scientific data does not support this claim of this common variant of the gene.
*There is a very rare variant of the MTHFR that can cause a severe condition called homocystinuria. It affects fewer than 1 in 200,000 people in most ethnicities.
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