Is it better to take methylated folate or folic acid? A Comprehensive Guide

January 12, 2026 •

4 min read

According to the CDC, approximately 40-60% of people may have a genetic variation that affects how their body processes folic acid. This statistic highlights a critical question for many supplement users: is it better to take methylated folate or folic acid for optimal absorption and health benefits?

Quick Summary

This guide details the differences between synthetic folic acid and the active form, methylated folate (5-MTHF). It explores the impact of the MTHFR gene variant, who benefits most from each type, and how to choose the right supplement for your health needs.

Key Points

Conversion Matters: Folic acid must be converted by the MTHFR enzyme into the active form, methylated folate, before the body can use it.
MTHFR Variant Impact: Many people (40-60%) have a gene variant that reduces the efficiency of converting folic acid, making methylated folate a more direct and effective option for them.
Unmetabolized Folic Acid (UMFA): High intake of synthetic folic acid can lead to UMFA accumulation, particularly in individuals with MTHFR variants, raising potential health concerns.
B12 Deficiency: Unlike high-dose folic acid, methylated folate does not mask the symptoms of a vitamin B12 deficiency, making it a safer option for some.
Cost vs. Bioavailability: Folic acid is a less expensive and more stable option, while methylated folate offers higher bioavailability and is better for those with impaired conversion.
Consult a Doctor: The best choice depends on individual health, genetics, and whether you are pregnant or planning to be; always discuss with a healthcare provider.

What is Folate, Folic Acid, and Methylfolate?

To understand which supplement form is right for you, it is essential to distinguish between these three key terms. Folate is the general term for vitamin B9, a nutrient found naturally in foods such as leafy greens, legumes, and eggs. Folic acid, on the other hand, is the synthetic version of folate, which is used to fortify foods and create many dietary supplements. Finally, methylated folate (specifically L-5-methyltetrahydrofolate or 5-MTHF) is the active, bioavailable form of B9 that the body can use immediately.

The Conversion Process: From Folic Acid to Methylfolate

When you consume natural folate from food or synthetic folic acid from supplements, your body must convert it into the active form, 5-MTHF, before it can be used for cellular metabolism. This complex, multi-step process relies on several enzymes, with the MTHFR (methylenetetrahydrofolate reductase) enzyme playing a critical role in the final conversion stage. The prevalence of MTHFR genetic variations is a central reason for the debate between methylated folate and folic acid, as these mutations can significantly impair the body's ability to perform this conversion efficiently.

Folic Acid vs. Methylfolate: A Head-to-Head Comparison

This table outlines the primary differences between the two forms of vitamin B9 supplementation to help you make an informed decision.


Aspect	Methylated Folate (5-MTHF)	Folic Acid (Synthetic)
Form	The active, natural form of folate, ready for immediate use.	The synthetic, oxidized form of folate, requiring enzymatic conversion.
Bioavailability	High bioavailability for everyone, bypassing the need for MTHFR enzyme conversion.	Bioavailability is dependent on MTHFR enzyme function; lower for individuals with genetic variants.
MTHFR Variants	Ideal for individuals with MTHFR gene variations, as it bypasses the conversion step.	Less effective for those with MTHFR variants, potentially leading to lower active folate levels.
Unmetabolized Folate	Does not lead to the accumulation of unmetabolized folic acid (UMFA) in the bloodstream.	Can lead to UMFA buildup in the blood, especially with high doses and impaired MTHFR function.
B12 Deficiency	Does not mask the symptoms of vitamin B12 deficiency.	High doses can potentially mask the neurological symptoms of B12 deficiency.
Stability & Cost	Generally less stable than folic acid and often more expensive.	Highly stable, making it ideal for fortified foods; typically less expensive.
Research History	Newer to the market with growing research; evidence supports its efficacy.	Decades of research support its use, particularly for neural tube defect prevention.

Who Should Consider Methylated Folate?

Methylated folate, or 5-MTHF, is often recommended for specific individuals for whom standard folic acid may not be the optimal choice. The most common group includes those with a known MTHFR gene variant. For these individuals, their body's ability to convert folic acid into its active form is compromised, making supplementation with 5-MTHF a more reliable method for maintaining adequate folate levels. The benefits of this approach extend to potentially preventing recurrent miscarriages and improving pregnancy outcomes in affected women.

Another significant advantage of methylated folate is that it avoids the accumulation of unmetabolized folic acid (UMFA) in the body. While the long-term effects of UMFA are still being studied, some research suggests potential negative health outcomes, including interference with folate metabolism and an increased risk of certain cancers, though this remains controversial. Furthermore, because methylated folate does not mask the signs of vitamin B12 deficiency, it is often a safer option for those with concerns about this condition.

The Case for Folic Acid

Despite the benefits of methylated folate, folic acid has a proven and important place in public health. Its effectiveness in preventing neural tube defects (NTDs) is well-established through decades of research and fortification programs. For many people without MTHFR variants, folic acid is effectively converted and utilized by the body, making it a perfectly viable and cost-effective option. Leading health organizations, including the CDC, continue to recommend folic acid supplementation, largely because of this robust historical data. Its stability also makes it the preferred form for fortifying grains and cereals, ensuring a widespread and reliable intake of folate.

Making the Right Choice for You

Determining the right supplement for you is a personal decision that should be made in consultation with a healthcare professional. While genetic testing can confirm the presence of MTHFR variants, it is not always necessary. If you are planning a pregnancy, have a family history of NTDs, or experience conditions related to poor folate metabolism, discussing methylated folate with your doctor is a wise step. However, for most of the population, a standard prenatal vitamin containing folic acid is a safe and effective option, supported by a strong public health track record.

Conclusion

Ultimately, whether it is better to take methylated folate or folic acid depends on individual genetics, specific health needs, and guidance from a healthcare provider. While folic acid remains a cost-effective and proven method for preventing neural tube defects in the general population, methylated folate offers a superior solution for individuals with MTHFR gene variants, providing better bioavailability without the risk of UMFA buildup or masking B12 deficiency. Both forms play a critical role in promoting health, but understanding their distinct metabolic pathways allows for a more personalized and effective approach to supplementation.

A list of Folate-Rich Foods

Leafy Greens: Spinach, kale, romaine lettuce
Legumes: Lentils, chickpeas, black beans
Asparagus: High in natural folate
Avocado: A good source of folate and healthy fats
Citrus Fruits: Oranges and grapefruits
Eggs: A moderate source of folate
Beets: A vegetable rich in folate
Beef Liver: One of the most concentrated sources of folate

Visit the Linus Pauling Institute for more information on the functions and metabolism of folate.

Frequently Asked Questions

The primary difference is their form and how the body uses them. Folic acid is a synthetic version that requires conversion by the MTHFR enzyme to become active. Methylated folate is the active form that the body can use immediately, bypassing the conversion process.

Individuals with a genetic variation in the MTHFR gene should be most concerned. This mutation impairs the body's ability to convert folic acid efficiently, making methylated folate a more reliable option for ensuring adequate folate levels.

Yes, genetic testing is available to determine if you have an MTHFR gene variant. This can help guide your decision on whether to supplement with folic acid or methylated folate, especially if you have fertility issues, a history of miscarriages, or concerns about nutrient absorption.

Methylated folate is considered safe and is often recommended for pregnant women with MTHFR variants. It provides the active form of folate directly to support fetal development, including the prevention of neural tube defects. However, pregnant women should always consult their doctor before changing supplements.

Folic acid has been used for decades with extensive research demonstrating its effectiveness, especially for preventing neural tube defects. It is also more stable and cost-effective, making it ideal for widespread food fortification programs.

Excessive intake of synthetic folic acid can lead to the build-up of unmetabolized folic acid (UMFA) in the bloodstream, particularly in individuals with MTHFR variants. Some studies suggest this may have potential long-term health implications, but more research is needed.

No, methylated folate is not known to mask the neurological symptoms of a vitamin B12 deficiency in the same way that high doses of folic acid can. This is another reason it may be considered a safer alternative for some individuals.