L-methylfolate (also known as L-methylfolate, 5-methylfolate, 5-MTHF, prescription Deplin, 5-CH3-H4folate, or simply methylfolate) is the folate your body uses to fulfill it’s many essential methylating functions such as neurotransmitter production, DNA and RNA synthesis (after it’s converted to 5,10-methylenetetrahydrofolate), cancer prevention, homocysteine processing (and heart and vascular health), red blood cell production, detoxification, and much more.
Food Sources of L-methylfolate
Foods high in L-methylfolate include:
- Sprouted legumes (mung bean, lentil, chickpea, etc)
- Spinach
- Romaine Lettuce
- Cauliflower
- Asparagus
- Broccoli
- Kale
- Cabbage
- Strawberries
- Other berries
- Oranges, grapefruit, and their juices
- Fermented foods such as kefir, water kefir, sauerkraut
- Brewer’s yeast
- Peas
- Sweet peppers
- and more
Grains such as wheat, corn, and rice are low in folate, yet throughout the world they are a foundational food source, resulting in low folate status in most people. Meat is generally low in folate, except for liver, which is high in non-methylated (not 5-MTHF) folate.
Most fresh green plant sources of folate have between 50% and 100% of their folate in the active L-methylfolate form, with the average green leaf seeming to have about 80% of its folate in the L-methylfolate form. Virtually none of the folate in fresh food is folic acid, and virtually all of it is reduced (ready to be methylated if not already methylated).
Dried legumes such as lentils, chickpeas, and white beans have the highest folate concentration of any food. However, they are mostly non-methylated, being primarily tetrahydrofolate, followed by 5-formyl-tetrahydrofolate and 5-methyl-tetrahydrofolate. However, amazingly, sprouting legumes for four days causes a 3- to 4-fold increase in total folate, a near-complete conversion of the folate to L-methylfolate, and a spike in vitamin C content that protects and stabilizes the 5-MTHF.
Eating legumes sprouted for 4 days is quite possibly the single most powerful way of increasing your body’s supply of L-methylfolate (aside from 5-MTHF supplementation).
Bacteria and yeasts are folate factories, and hence fermented foods are excellent sources of active folate.
L-methylfolate (5-MTHF) supplements are rapidly gaining in popularity because they work. However, there is a lot of confusion out there as to whether people low in L-methylfolate can get L-methylfolate from food. Food scientists unequivocally find that food is an excellent source of active 5-MTHF. If you’re eating a lot of the right types of folate-rich food, L-methylfolate supplementation is likely unnecessary. If you have MTHFR gene mutations, eating fresh folate-rich foods becomes even more important. That said, popping a pill to get 1,000 or more micrograms in one swallow is a lot easier than eating fresh greens and fresh or frozen berries every day. Even so, in the long run you will be healthiest and happiest if you eat high-folate foods every day.
Effects of food processing on folate
Folate (L-methylfolate included) is relatively fragile and degrades when food is processed, so it is important to buy fresh green vegetables (primarily leafy greens and cruciferous) from the fresh produce department. Local and organic greens likely have more folate. Berries seem to last frozen for months without losing folate. Eat vegetables raw for best folate availability, or gently steam your veggies (5 minutes or less) to preserve the folate in the food. Boiling causes the folate to leech into the water, so avoid boiling greens unless you add them to a liquid you’ll consume (such as a soup) in the last few minutes of simmering. Green smoothies with raw spinach or kale and organic strawberries is a folate powerhouse. Vitamin C in food powerfully protects folate from breaking down. Hence, foods with both folate and vitamin C (such as broccoli and citrus) are super sources of L-methylfolate.
Are you eating your fresh greens and berries?
As mentioned above, L-methylfolate is essential for brain health. For most people, eating raw or lightly cooked dark leafy greens, cruciferous vegetables, and other fresh vegetables is required if you want to have a happy, healthy brain.
If you’re curious about methylated vitamin B12, we have also published a discussion of food sources of methylated vitamin B12 (methylcobalamin).
References
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Paul M. Finglas & Anthony J.A. Wright. Folate bioavailability and health. Phytochemistry Reviews 1: 189–198, 2002.
Shohag MJ, Wei Y, Yang X. Changes of folate and other potential health-promoting phytochemicals in legume seeds as affected by germination. J Agric Food Chem. 2012 Sep 12;60(36):9137-43. doi: 10.1021/jf302403t. Epub 2012 Aug 27. PubMed PMID: 22906127.
Iyer R, Tomar SK. Folate: a functional food constituent. J Food Sci. 2009 Nov-Dec;74(9):R114-22. doi: 10.1111/j.1750-3841.2009.01359.x. Review. PubMed PMID: 20492126.
Johan D. M. Patring, Sofia B. Hjortmo, Jelena A. Jastrebova, Ulla K. Svensson, Thomas A. Andlid, I. Margaretha Ja ̈gerstad. Characterization and quantification of folates produced by yeast strains isolated from kefir granules. Eur Food Res Technol (2005).
Cornelia M. Witthoft, Karin Forsskn, Lena Johannesson and Margaretha Jagerstad. Folates – food sources, analyses, retention and bioavailability. Scandinavian Journal of Nutrition/Naringsforskning Vol 43:138-146, 1999.
