June 06, 2015
MTHFR for Preconception and Pregnancy Health: What You Need to Know
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Emily Rydbom, CN, HN, CNP & Michael Stone, MD, MS, IFCMP 

What is MTHFR?

Methylenetetrahydrofolate reductase (MTHFR) is an enzyme; this enzyme helps our metabolism work. It is coded to work effectively by the MTHFR gene. There can be many altered codes for the same gene and enzyme. Each alteration in the code is called a single nucleotide polymorphism or SNP. There are over 40 known MTHFR gene SNP’s. The MTHFR enzyme works as one of the many enzymes of normal metabolism. All of us need the active functioning of our MTHFR enzyme to work in combination with many other enzymes for a normal metabolism. The MTHFR gene codes for a protein called methylenetetrahydrofolate reductase that converts one form of folate (5,10-methylenetetrahydrofolate) into a different form of folate (5-methyltetrahydrofolate), in other words, the MTHFR enzyme converts one form of folate into the most active and usable form of folate for your body.

There are 5 biochemical cycles that interact like pieces of a puzzle, with MTHFR as a cofactor: Urea cycle, Neurotransmitter cycle, Folate cycle, Methionine (methylation), and Trans-sulfuration cycle.


What does it mean when we say “MTHFR polymorphism?”

Polymorphism: Any change in a gene coding sequence which is altered from the normal code. We all have many changes from normal–DNA sequence variations. DNA is made of up two strands of molecules.  Each strand is an allele.  One allele is from our father and one from our mother. You can have a polymorphism on either or both strands. Each of these polymorphisms is a gene variation. A single strand variant from one parent means you are heterozygous for that gene sequence. A variant from each parent means you are a homozygous recessive variant for that gene. So, heterozygous means a single recessive variant, and homozygous means a double recessive variant.

When an MTHFR polymorphism is present, then you have a decreased genetic ability to convert folate to the form that is readily available for use, called methylfolate. This genetic inability to methylate decreases your ability to make that conversion–from 30% (heterozygote) to 90% (homozygote).

Some of the effects of MTHFR polymorphism

  • Hyperhomocysteinemia (High homocysteine—requiring Vitamin B6, Folate and  Vitamin B12 to decrease levels)
  • Heart disease, hypertension, or stroke
  • Anxiety and depression, insomnia and migraines
  • Cancer
  • Addictions: smoking, drugs, alcohol—chemical sensitivity


Why is it important to know my MTHFR genetic status preconception and for pregnancy?

Your ability to methylate or activate B vitamins affects nearly all parts of your body. If you are genetically predisposed to MTHFR, then it can affect your ability to conceive and carry a healthy pregnancy.

Here are some of the effects of MTHFR on reproductive health:

  • Neural tube defects: spina bifida, anenchephaly, and Chiari malformation
  • Autism spectrum disorder
  • Cleft lip and cleft palate
  • Pregnancy Induced Hypertension
  • Miscarriages and blood clots
  • Male/Female infertility

What MTHFR genes are the most researched?



How do I check to see if I have MTHFR?

Your primary care physician can order a blood test for you, however, we like the genetic test from 23andme. 23andme is a salivary genetic test that will not only let you check your MTHFR status, but will also check other genetic cofactors that can affect your MTHFR status. It will also give you a look into your detoxification pathways to see if you have impaired detoxification pathways.

  A mother handing chard to her daughter

How do I to manage MTHFR nutritionally?

Food first always. You can focus on MTHFR rich foods by choosing dark leafy greens, legumes, Brewer’s yeast, and animal protein, however, most people with MTHFR, especially those of you that are looking to become pregnant or are pregnant will need nutritional supplementation.

Focus Nutrients to support MTHFR Polymorphism

Essential Amino Acids: L-Methionine, L-Cysteine

Fats: Omega-3 Fatty Acids

Carbohydrates: Phytonutrient Spectrum

Vitamins: Vitamin B6, Methylfolate, Methylcobalamin-Vitamin B12,  a complete methylated or phosphorylated B Complex, and Choline

Minerals: Zinc, Iron

Please consult with your primary care provider to ensure that there is an existing diagnosis of MTHFR Polymorphism before you implement diet or supplemental changes.


Have a Happy and Healthy Day!




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Posted on Jun 06, 2015