Printable guide · 4 sections · 22 checkpoints

The Methylation & MTHFR Primer

A plain-English primer on methylation, the MTHFR gene, folate forms and how to talk to your clinician about genetic results — without the internet fear.

Methylation is one of the body's most common chemical processes, and MTHFR is one of the most searched genes online. This primer separates what's well established from what's speculative, so you can have a productive conversation with a professional.

Use it alongside our methylation guide and MTHFR guide.

1. Know the basics

Methylation is the transfer of a methyl group (one carbon, three hydrogens) between molecules.

Methylation supports DNA regulation, neurotransmitter and hormone metabolism, and homocysteine processing
Folate, B12, B6, B2, choline and betaine all participate in the methylation cycle
The MTHFR enzyme converts folate into its active form, 5-MTHF (methylfolate)
Common variants (C677T, A1298C) can reduce enzyme activity to varying degrees

2. Keep variants in perspective

Having a common MTHFR variant is normal — a large share of people carry at least one copy.

A variant is not a diagnosis
Homocysteine blood testing reflects how your methylation is functioning in real life
Diet quality strongly influences outcomes regardless of genotype
Public health guidance (e.g., CDC) still recommends folic acid for neural tube defect prevention, including for people with MTHFR variants
Some medical organizations do not recommend routine MTHFR testing for specific clinical questions — ask your clinician why a test is or isn't useful for you

3. Foundations that support methylation

These habits are reasonable for nearly everyone.

Eat folate-rich foods: leafy greens, legumes, asparagus, avocado
Get adequate B12 from animal foods or fortified sources
Include choline sources such as eggs
Include betaine sources such as beets, spinach and whole grains
Moderate alcohol, which interferes with folate metabolism
Prioritize sleep and stress management

4. Questions to bring to your clinician

Bring your results and these questions to your appointment.

Should I check homocysteine, folate or B12 levels?
Does my genotype change any recommendations for me?
Is methylfolate or methylcobalamin appropriate for me, and at what dose?
Do any of my medications affect folate or B12?
How and when should we retest?
Which results should I ignore as low-value?

FAQ

Guide FAQs

Should I take methylfolate if I have an MTHFR variant?

Not automatically. It depends on your diet, lab values, medications and life stage. Discuss it with a qualified clinician rather than self-prescribing high doses.

Can a genetic test tell me if I'm methylating poorly?

A genetic test shows your genotype — the potential for reduced enzyme activity. Blood markers like homocysteine show how the system is actually working today. Together they're more useful than either alone.