Is There a Relationship Between L-Methylfolate and Cancer?

Is There a Relationship Between L-Methylfolate and Cancer?

Katie Stone - Naturopath

Written By:

Katie Stone - Naturopath
Jamie Hope - Founder of Methyl-Life

Medical Reviewer:

Jamie Hope - Founder of Methyl-Life
Kari Asadorian - Bachelor of Science in Nursing

Edited By:

Kari Asadorian - Bachelor of Science in Nursing

Updated On:

March 26, 2025

Table of Contents

    To start, let’s explain a bit about how methylfolate makes things work in the body. It fuels the methylation biopathway within the body which is responsible for many things such as:

    • Boosting SAMe levels which make and help balance neurotransmitters for optimal brain health
    • Boosting Glutathione levels which kicks off detoxification allowing you to clear the tough things like heavy metals, BPAs, environmental and micro toxins to name a few (Glutathione is the body’s greatest antioxidant)
    • Reducing Homocysteine levels which when high can cause negative cardiovascular events like heart attacks, strokes, deep vein thrombosis, aneurisms, and more. Too much homocysteine also makes it hard for the body to fight off infection and allow the immune system to function properly
    • Crosses the blood-brain barrier to assist with executive function as well as improving Dementia and Alzheimer’s disease symptoms.
    • Helps repair the myelin sheath which can positively impact neuropathy
    • Can reduce the incidence of miscarriage during pregnancy as well as protect the fetus from birth defects
    • Can help prevent DNA damage to our cellular structure which is important in the fight against cancer

    Is there a relationship between L-Methylfolate and Cancer?

    There’s a lot of buzz out in the research world around this topic. Does it cure cancer? Does methylfolate cause cancer? Does it prevent cancer? It might surprise you to know that this “life-saving” vitamin for some can actually cause unwanted symptoms at times. Depending on your health history, some of these “healthy” nutrients can actually be harmful for some people, even though they’re very helpful for most people most of the time. Stay with us and you’ll learn more about how methylfolate fuels the body and how research tells us it interacts with cancer.

    So you can see methylfolate does a great deal of good within the body and affects a number of vital systems within it.


    But let’s move on to the concept of cancer and tumor growth. Understandably, the “C” word tends to put everyone on high alert because we all know someone close to us who has battled it. We may have even battled with it ourselves. It’s an ugly disease that tends to elicit extreme feelings of trauma and suffering. Before I began my methylfolate journey, I lost my mother to Ovarian Cancer. So I know the graveness of its concern at the very core of my being.


    There are many theories about where cancer comes from, but at the root of it, most seem to agree that when things go awry in the body with DNA/RNA and our cellular structure, it can cause our genes to make faulty enzymes. Some think this can happen from environmental toxicity, some suggest it can happen from excessive parasite or microbial overgrowth, and of course there are many other theories for where the various types of cancer can come from. But if most agree cancer has to do with changes in the cellular structure, then it would stand to reason that having a “protectant” against these kinds of changes ‘onboard’ would be very good for us in the fight against cancer. Such a protector could also help our bodies make the beneficial substances that might otherwise control the abnormal cells. Enter … Methylfolate … which has been shown in studies to help prevent DNA damage. And as we just mentioned, cancer can appear when there is DNA damage and then abnormal cells begin to grow rapidly. So the conclusion is that in general methylfolate may be a helpful nutrient in the “prevention” of certain types of cancers. (Research has been done that showed a correlation between folate supplementation and a decreased occurrence of colon cancer).


    Now it’s imperative that you don’t get synthetic folic acid and methylfolate mixed up because synthetic folic acid has actually been questioned in various studies as a “potential source” of cancer, especially for those with MTHFR (a genetic mutation which affects folate metabolism in the body and is responsible for creating the correct form of folate that your cells need to use directly, methylenetetrahydrofolate reductase). If you take synthetic folic acid and have an MTHFR mutation like over half of the world’s population does, then you can’t make this enzyme properly and your body will make a faulty version of the enzyme.


    So the thing to do is AVOID SYNTHETIC FOLIC ACID when we have MTHFR because we can’t convert into the correct form of the folate enzyme (and instead we want to be sure we’re taking the correct form of methylfolate instead). By doing this studies indicate we might we actually be guarding ourselves against some forms of cancer. What the research shows is that “the timing” of the supplementation is critical. One study showed that taking folate prior to the existence of precancerous tumor cells could actually prevent tumor development. Additionally a large number of risk factor studies have shown that a higher intake of folate, as well as vegetables and fruit, is associated with a decreased risk of colorectal polyps and cancer. 


    Now let’s talk about how methylfolate works and behaves within the body when it’s not providing such good health? Let’s start with an example, the autoimmune condition you may already be familiar with, Psoriasis. When someone has Psoriasis, the body over-produces skin cells and that creates excess plaque build-up on the skin’s surface, it’s referred to as dermatitis. Interestingly enough, methotrexate (typically a chemo therapy drug), can be prescribed to folks with more extreme cases because it hinders the Psoriasis outbreaks by shutting down the methylation pathway (that’s methotrexate’s mechanism of action). Psoriasis tends to use the methylation pathway to get itself going crazy. If you have Psoriasis and you add methylfolate (aka methylation pathway fuel) to your body, you may find it likely that the methylfolate will push the Psoriasis to do even more of what it’s already doing at an even more accelerated rate (in other words, making even more of the excess skin cell plaques at an even faster rate). Consequently, methylfolate might actually have a worsening effect on Psoriasis for some people (especially for those who have found methotrexate to have ‘helped’ their Psoriasis get better). Methotrexate closes the methylation pathway down as its mechanism of action, while Methylfolate’s mechanism of action is to open up the methylation biopathway which provides fuel for the body to function better.


    Sometimes I like to think of methylfolate a bit like rocket fuel … when your body is needing fuel, it’s a great source for feeding the body’s life-force, which is one reason why it’s so vital to take when one is pregnant and why it can have such dramatic and profoundly positive effects for some peoples’ major health concerns. However, methylfolate may fuel with life-force something you do not want it to as well, like the Psoriasis condition. Sometimes it may not be discriminatory like we would prefer.

    Could taking L-methylfolate be a negative thing for those with pre-existing cancerous lesions?

    SO … If you have an active tumor in your body, you may actually be fueling it to grow faster by taking methylfolate (whether it’s benign or malignant). Taking high doses of methylfolate (once early lesions are established) appears to increase tumor growth. When cancer already exists in the body, the rapidly proliferating tissues, including tumors, have an increased requirement for nucleotides; which basically means many cancers up-regulate folate receptors (Ulrich & Potter, 2007). Essentially just as sugar can act as a kind of “food” to tumors, so it appears that folates may also act as a type of “feeder” to tumors. Only an oncologist can best speak to these specifics based on any particular type of cancer (and its main mechanisms of action for growth), so it is highly recommended that anyone with cancer talk to their oncologist before taking methylfolate.


    In general, Dr. Rawlins’ point of view is to talk to your Oncologist first. But overall, in general the rule of thumb might be, if you’re in the midst of a chemotherapy treatment that affects the methylation pathway (purposely trying to close it – with a drug like methotrexate), you may want to stop taking methylfolate during your treatment time. However, when that treatment is over, you may choose to go back onto the methylfolate (as it can be a DNA protector as well).

    To Sum It Up

    So let’s wrap it and summarize what we’ve learned … Methylfolate is an amazing nutrient that’s doing great things for so many people in the world today, specifically it’s helping our bodies get the right form of the folate enzyme we need for optimal health and potentially even cancer prevention. However, understanding when it’s right to take methylfolate and when it might not be the very best for your personal health is imperative. If you have abnormal, high-risk lesions, taking methylfolate may potentially fuel the growth of those cells. So do your research, talk to your Oncologist AND PAY ATTENTION to your personal health and your body’s response when you take a nutrient. Be aware of the connections that might need to be made between the conditions you have and the things you want to see improve along with the options available out there to help you. Don’t just blindly take something because ‘it’s the new fad’ or someone told you ‘it’s great’. Nutrition is individual to you and is often based on your specific genetics, so LISTEN TO YOUR BODY - because it carries great wisdom!

    Product Recommendations

    L Methylfolate Supplement 2.5 mg - Methyl-Life® Supplements

    L Methylfolate Supplement 2.5 mg
    (15)

    $29.00

    • Supports Healthy DNA Synthesis10
    • Promotes Balanced Homocysteine Levels9
    • 3rd-Party Tested for Purity, Potency & Safety
    • 90 Vegan, Non-GMO, Chewable Mint Tablets

    References

    1. Williams JD, Jacobson EL, Kim H, Kim M, Jacobson MK. Folate in skin cancer prevention. Subcell Biochem. 2012;56:181–197.

    2. Ulrich, Cornelia M., and John D. Potter. “Folate and Cancer—Timing Is Everything.” Jama, vol. 297, no. 21, 2007, p. 2408

    Katie Stone - Naturopath

    About the Author

    Katie is a qualified Naturopath (BNatMed) and freelance writer from New Zealand. She specializes in all things health and wellness, particularly dietary supplements and nutrition. Katie is also a dedicated runner and has completed more half-marathons than she can count!

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