What is the best form of folate?
3 forms compared by what actually reaches your bloodstream. Absorption ranges from 85% to 98% — a difference that matters more than the milligrams on the label.
Ranked by absorption
Higher means more of the dose reaches youShort answer
Vitamin B9 (Folinic Acid) absorbs best — 98%.
Medical-grade folate bypassing genetics. Typical dose 400-1000 mcg, about $100 a month. The cheapest option is Vitamin B9 (Folic Acid) at $5, but its absorption score is only 85 of 100.
Every form side by side
| Form | Absorbed | Elemental | Cost / 10 mg delivered | Per month | Dose |
|---|---|---|---|---|---|
| Vitamin B9 (Folinic Acid) | 98% | — | $48.59 | $100 | 400-1000 mcg |
| Folate (5-MTHF) | 95% | — | $11.70 | $20 | 400-800 mcg |
| Vitamin B9 (Folic Acid) | 85% | — | $3.27 | $5 | 400-800 mcg |
What not to take with folate
Same rules for every form — the interaction belongs to the mineral, not the carrierSeparating the two by two to four hours removes most of these: they compete for the same transporters in the gut, not in the bloodstream. Splitting the day is what solves a conflict — dropping one of the two is rarely necessary.
Medication interactions
Interferes with folate metabolism · May need folate supplementation
Used therapeutically to counteract methotrexate · Prescribed specifically as rescue therapy
May counteract folate depletion from seizure medications · Consider supplementation with medical supervision
May overcome folate antagonism · Often recommended with this IBD medication
Prescription medicine is your doctor's call, not ours — this is what the records list.
How much is too much
Upper limit for adults: 1000 mcg a day, per NIH ODS.
Signs of overshooting it: rare toxicity from folate itself:, may mask vitamin b12 deficiency, digestive upset at very high doses, sleep disturbances (rare).
14 reports to the FDA name folate as the suspect product.
Most reported: fatigue (3), nausea (3), palpitations (2), pruritus (2). Serious outcomes: 81% of them.
Counted from FDA CAERS by parsing each report's product list, not by keyword — a report where the product was merely present does not count.
Head to head
How to read this
- Absorption is the share of the dose that reaches your bloodstream — the number that decides whether the milligrams on the label mean anything.
- A cheaper form at half the absorption is not cheaper per unit delivered.
- Safety here reflects tolerance at normal doses, not toxicity risk.
- Evidence A means the form itself was studied, not just the parent compound.
Compiled by Denis, who maintains this database and holds no medical qualification. Absorption figures and cost-per-absorbed values are derived by published formulas from cited sources — see the arithmetic.
Common questions
What is the best form of folate?
Vitamin B9 (Folinic Acid) — it scores 98 of 100 on absorption, the highest of the 3 forms here. Medical-grade folate bypassing genetics. Typical dose 400-1000 mcg.
Which form of folate is worst absorbed?
Vitamin B9 (Folic Acid) at 85%. It is usually the cheapest option, which is exactly why it ends up in budget products.
Is the expensive form of folate worth it?
Compare per unit delivered, not per bottle. Vitamin B9 (Folic Acid) costs $5 a month at 85% absorption, Vitamin B9 (Folinic Acid) costs $100 at 98%.
How much folate should you take?
Doses differ by form: Vitamin B9 (Folinic Acid) 400-1000 mcg; Folate (5-MTHF) 400-800 mcg; Vitamin B9 (Folic Acid) 400-800 mcg.