Methylation is a crucial biochemical process that helps regulate everything from gene expression and detoxification to fertility, brain health, and immune function. Though it’s rarely taught outside advanced science courses, methylation has become a hot topic in both genetics and functional medicine, especially when it comes to fertility, pregnancy, and chronic health conditions.

We’ll break down what methylation actually is, why it matters for reproductive and overall health, and how you can support it through lifestyle, nutrition, and targeted testing.

What is methylation?

You’ve probably heard the word methylation tossed around—maybe while researching prenatal vitamins, genetics, or fertility—and thought, “Wait, should I know what that is?” If so, you're in exactly the right place. 

Methylation isn’t something most of us learned about in eighth-grade biology. It started gaining traction in scientific circles in the early 2000s, especially with the rise of epigenetics (the study of how your environment and habits can turn your genes "on" or "off" without changing your actual DNA). Over the last decade or so, methylation has officially moved into the wellness world, and for good reason.

You can think of methylation like little dimmer switches on your genes. Instead of rewriting your genetic code, these switches control how strongly certain genes are expressed—kind of like deciding how bright you want a lamp to glow.

Methylation supports a number of essential cellular processes, including:

• Metabolizing vitamins and nutrients
• Detoxifying harmful substances
• Repairing DNA
• Supporting brain function
• Regulating immune health
• Producing key neurotransmitters like serotonin and dopamine

When methylation is working properly, your body runs smoothly—repairing, detoxing, growing, and protecting exactly when it should. But when methylation gets out of balance, things like energy, mood, immunity, and fertility can start to slip.


RELATED:The impact of methylation on fertility and pregnancy: Why B vitamin form matters

So methylation is a good thing?

Definitely—but like most things in biology, it’s all about balance. You want enough methylation happening in the right places, at the right time. If there’s too much or too little, it can create issues. Research has linked poor methylation patterns to conditions like cancer, cardiovascular disease, mood disorders, and infertility.

But the good news is, unlike your genes, your methylation patterns are influenced by what you eat, how you sleep, how you manage stress, and your environment. In other words, you can actually do something about it.

How methylation affects fertility

In women, methylation is critical for egg quality. It helps eggs mature properly, ensures chromosomes divide correctly, and protects the egg’s DNA for early embryo development. When methylation is off—because of aging, low folate or B-vitamin levels, oxidative stress, or environmental toxins—egg quality can decline. This increases the risk of infertility, miscarriage, or chromosomal abnormalities.

And yes, methylation matters for sperm, too.

Healthy methylation helps sperm develop properly and keeps their DNA stable. When it's disrupted, sperm can have DNA fragmentation—tiny breaks in the genetic material—which can lower fertility, increase miscarriage risk, and reduce embryo quality. Even if sperm counts look normal, broken DNA can still be a hidden problem.

How to support healthy methylation 

You don’t have to master biochemistry in order to support healthy methylation—you just have to nourish it with the essentials:

• Methylated folate (B9)
• Vitamin B12 (preferably as methylcobalamin)
• Vitamin B6
• Riboflavin (B2)
• Choline

Also, reducing toxic exposures, like environmental chemicals, heavy metals, and synthetic additives, can have a measurable impact on methylation, and with the right support from diet, sleep, and gut health. 

Genetic testing for methylation

When people say they’ve had “methylation testing,” they’re usually talking about genetic testing for SNPs—tiny DNA tweaks that can subtly shift how efficiently your body runs the methylation show. The MTHFR gene helps your body convert folic acid into methylfolate, the active form your cells actually use. About 30–40% of people discover they have an MTHFR variant after genetic testing, and most of these individuals are perfectly healthy. Whether or not you feel any MTHFR-associated symptoms usually depends on a multitude of other factors, like other genes, diet, lifestyle, and nutrient levels. One of the reasons I recommend my preconception patients take a prenatal with methylated folate is because they may not know whether they carry an MTHFR variant—and using the active form helps ensure they’re getting bioavailable folate their body can actually use during this critical window. 

Who might benefit from a genetic methylation test?

In my clinical practice as a reproductive genetic counselor, I find methylation testing can be informative for specific situations, like patients dealing with recurrent pregnancy loss, unexplained infertility, or IVF that just isn’t working. It can also shed light on cases involving chronic disease, elevated homocysteine, a family history of cardiovascular disease, neurological conditions, or complex inflammatory patterns.

When's the best time to get a genetic methylation test?

There’s no one-size-fits-all answer. Including methylation-focused testing as part of preconception genetic screening can be helpful if you're planning pregnancy, but testing can be useful at any point when you're looking to get a clearer picture of your health.

Can a genetic methylation test boost your chances of pregnancy?

Methylation-focused genetic testing doesn’t guarantee improved fertility outcomes, but for certain individuals, it can help identify underlying factors that may be affecting reproductive health. The value of genetic testing lies in its personalization; recommendations should be tailored to each individual’s medical history, family background, and personal goals.  There are a multitude of genetic panels that can shed light on methylation which may be helpful for some individuals and not for others. 

Testing can include: homocysteine levels, SAMe/SAH ratios, serum folate, B12, B6, methylmalonic acid, organic acid panels, and epigenetic age testing. With so many tests on the market, some reputable and many not, it’s crucial to work with a clinician who understands the science and curates the right testing for you based on your clinical history and personal goals.  Misinterpreting results may lead to unnecessary anxiety and/or ineffective interventions. And no matter the result, context is key—genetic variants alone don’t tell the whole story.

Think of methylation testing as a conversation starter—one that, when combined with lab data, clinical insight, and the right personalized care, can help guide smarter, more proactive decisions. 


RELATED:WeNatal FAQs: When to start prenatals, fertility tips, and supplement advice for both partners

A note from WeNatal on genetic methylation testing

At WeNatal, we’re continually inspired by the evolving science of epigenetics and methylation, especially as it relates to preconception health and fertility for both women and men. Methylation plays a central role in everything from DNA repair and hormone regulation to egg and sperm quality, which is why it’s a topic we take seriously when formulating our products and guiding wellness conversations.

While genetic testing can provide helpful insights, supporting methylation starts with the foundations: nutrient-rich food, restorative sleep, toxin reduction, and the right forms of key vitamins like methylated folate, B12, and choline. Our supplements are intentionally designed with bioavailable nutrients that align with current research on methylation and reproductive health, whether or not you know your MTHFR status.

We believe that understanding your unique biochemistry is a powerful tool, and that small, consistent steps can make a big impact. Whether you’re just starting to learn about methylation or exploring testing as part of your fertility journey, we’re here to support you with science-backed guidance and intentional nourishment every step of the way.

RELATED: PCOS & fertility: How to improve your odds—From TTC to pregnancy

References

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Feinberg, A. P. (2007). Phenotypic plasticity and the epigenetics of human disease. Nature, 447(7143), 433–440. https://doi.org/10.1038/nature05919

Karimi, R., & Fadaei, R. (2023). MTHFR gene polymorphisms: A single gene with wide-ranging effects on health. Genes, 16(4), 441. https://doi.org/10.3390/genes16040441

Li, M., et al. (2024). The role of epigenetics in women’s reproductive health: A focus on oocyte maturation and early development. Frontiers in Endocrinology, 15, 1399757. https://doi.org/10.3389/fendo.2024.1399757

Sharp, G. C., & Lawlor, D. A. (2019). Paternal impact on the epigenome: Implications for offspring health. Nature Reviews Endocrinology, 15(9), 503–511. https://doi.org/10.1038/s41574-019-0224-6

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Vibrant Wellness. (n.d.). Methylation and detoxification: Understanding the role of methylation in health. Retrieved July 22, 2025, from https://vibrant-wellness.com/tests/cardiovascular/methylation-panel

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