Quatrefolic vs Metafolin: Which Folate Form

Quatrefolic and Metafolin are both branded versions of 5-MTHF, the already-active form of folate, so neither is a different or superior vitamin. They are the same molecule attached to a different salt: Quatrefolic uses a glucosamine salt, Metafolin uses a calcium salt. Both raise blood folate effectively, and the practical choice comes down to the stated 5-MTHF dose, price, and how the product is formulated rather than a real difference in the folate you end up using.

Because the active molecule is identical, the honest comparison is about the carrier and the label, not one brand outperforming the other. Our B-complex page and the low-mood guide cover where folate sits in mood and methylation support before the brand names.

Same active folate, two different salts

Folate has to reach a usable form before your cells can work with it. Ordinary folic acid needs several enzymatic steps, ending in the enzyme MTHFR, to become 5-methyltetrahydrofolate (5-MTHF), the form that circulates in blood and crosses into the brain. Both Quatrefolic and Metafolin skip that conversion by supplying 5-MTHF directly, which is why they are grouped together as “methylfolate.”

The difference is only the salt each brand pairs with the 5-MTHF to keep it stable and soluble. Metafolin is the calcium salt, the form used in much of the published 5-MTHF research and known for a solid stability record. Quatrefolic is the glucosamine salt, marketed for higher water solubility. Because these salts weigh different amounts, a milligram of one brand is not a milligram of pure folate; part of the weight is the carrier. That is why you compare the equivalent 5-MTHF content on the label, not the raw salt figure.

How Quatrefolic and Metafolin compare

Brand	Salt form	Standardised as	Human evidence base	Rough cost
Metafolin	Calcium salt of L-5-MTHF	Equivalent 5-MTHF per serving	Used in much of the 5-MTHF trial literature	Varies by retailer
Quatrefolic	Glucosamine salt of 5-MTHF	Equivalent 5-MTHF per serving	Marketed for high solubility; fewer head-to-head trials	Varies by retailer

The table makes the point plainly. Both are standardised to their 5-MTHF content, and the meaningful comparison is that number, not the salt. Metafolin has the deeper footprint in the research on the active folate, while Quatrefolic’s selling point is solubility. We leave the price and any direct potency-difference cells open because verified head-to-head data is limited and an invented figure would mislead more than help.

What the evidence shows

The strongest evidence is for the active 5-MTHF molecule rather than for one brand over the other. A randomised trial by Prinz-Langenohl and colleagues (2009) found that the calcium salt of 5-MTHF raised plasma folate at least as effectively as folic acid, and more so in women carrying the MTHFR 677 C→T variant, who convert folic acid less well. A review by Scaglione and Panzavolta (2014) explains why folic acid, folinic acid, and 5-MTHF are not interchangeable, and why the pre-converted 5-MTHF form bypasses the MTHFR step. Both Quatrefolic and Metafolin supply that same 5-MTHF. The NIH Office of Dietary Supplements folate fact sheet treats 5-MTHF as an accepted supplemental folate source. Direct brand-versus-brand human trials are scarce, so claims that one is clearly stronger should be read with caution.

What to look for in a methylfolate 5-MTHF supplement

Decide on the dose first, then read the label for the equivalent 5-MTHF amount in micrograms, because the branded salt weight overstates the folate you actually get. Look for a product that names either Quatrefolic or Metafolin explicitly, rather than a vague “folate blend,” so you know you are getting the active form and can match it to research. If your reason for choosing methylfolate is an MTHFR variant, that named active form is the point; if not, standard folic acid may serve you just as well for less. A B-complex that pairs the methylfolate with methylcobalamin B12 is a sensible format, since the two work together in methylation. Prioritise third-party testing for identity and purity. Our B-complex page sets out the criteria and typical doses, and the low-mood guide shows how folate fits alongside other supports. A named brand with a stated 5-MTHF dose beats a “high potency” claim on the front label.

When the premium is not worth it

If you have no reason to think you convert folic acid poorly, paying extra for a branded methylfolate buys little most people would notice, because ordinary folic acid raises folate well in the general population. The premium earns its place when you carry an MTHFR variant, when a clinician has recommended the active form, or when you want to match the dose used in 5-MTHF research. Choosing between Quatrefolic and Metafolin on the belief that one is dramatically more potent is the assumption to avoid; the human evidence points to the shared 5-MTHF molecule doing the work, not the salt. Buy on the stated dose, the formulation, and price rather than on a marketed difference between the two carriers.

Cautions

Methylfolate is generally well tolerated. Very high folate intake can mask a vitamin B12 deficiency by correcting the anaemia while nerve damage continues, which is one reason B12 belongs alongside folate in a good formula. Folate can interact with certain medications, including some anti-seizure drugs and methotrexate, so check with your prescriber if you take these. If you are pregnant, planning pregnancy, or managing a health condition, discuss folate dosing with your clinician, since needs and targets differ. Folate supports mood and methylation; it does not treat depression or any diagnosed condition. When in doubt, ask your prescriber or pharmacist before starting, whichever form you choose.

Sources

• Prinz-Langenohl R, Brämswig S, Tobolski O, et al. [6S]-5-methyltetrahydrofolate increases plasma folate more effectively than folic acid in women with the homozygous or wild-type 677C→T polymorphism of methylenetetrahydrofolate reductase. Br J Clin Pharmacol. 2009. doi:10.1111/j.1365-2125.2008.03378.x
• Scaglione F, Panzavolta G. Folate, folic acid and 5-methyltetrahydrofolate are not the same thing. Xenobiotica. 2014. doi:10.3109/00498254.2013.845705
• National Institutes of Health, Office of Dietary Supplements. Folate: Fact Sheet for Health Professionals. ods.od.nih.gov

This article is educational and not medical advice. Supplements support, not treat, mood, stress, and sleep. Check with your prescriber before starting a new supplement. See our disclaimer and get help.