The most effective way to lower folate levels is to stop taking folic acid supplements and reduce your intake of fortified foods. For most people, these two steps alone will bring blood folate down significantly within a few months. But before making changes, it helps to understand why your levels are high and whether that actually matters for your health.
Why Your Folate Might Be High
Folate is a B vitamin found naturally in leafy greens, legumes, and citrus fruits. Folic acid is the synthetic version added to foods and supplements. Your body handles these two forms differently, and that distinction matters when you’re trying to lower your levels.
The most common reason for elevated folate is straightforward: you’re taking in more than your body needs. This usually comes from a combination of a daily multivitamin or prenatal vitamin (which typically contains 400 to 800 mcg of folic acid), fortified grain products, and a diet already rich in natural folate. In the United States, folic acid is added by law to enriched breads, flours, pastas, rice, cornmeal, and many breakfast cereals. If you eat these foods regularly while also taking a supplement, you can easily overshoot your needs without realizing it.
Less commonly, high serum folate can signal something else going on. Pernicious anemia, a condition where the body can’t absorb vitamin B12, can paradoxically raise folate readings on blood tests. A recent blood transfusion can also temporarily elevate levels. If you haven’t been supplementing heavily and your folate is still high, these possibilities are worth exploring with your doctor.
Stop Supplements First
If you’re taking a folic acid supplement, stopping it is the single biggest lever you have. Your blood levels won’t drop overnight, though. Folate is stored in red blood cells, which live for about 120 days, so the decline happens gradually.
Research on patients who stopped folic acid supplementation found that red blood cell folate levels dropped steadily over six months, falling from roughly 1,900 micrograms per liter to about 676. Levels continued to decline more slowly after that, stabilizing around 455 micrograms per liter at the nine-month mark. So expect a meaningful drop within three to six months, with full stabilization taking closer to nine months.
If you’re taking a multivitamin, check the label. Most contain 400 mcg of folic acid. You can switch to a multivitamin without folic acid, or simply stop taking it if folate is your main concern. Prenatal vitamins contain even higher amounts, so if you’re not pregnant or planning to become pregnant, talk to your provider about whether you still need one.
Cut Back on Fortified Foods
Reducing fortified foods is the second major step. The FDA requires folic acid to be added to all enriched grain products in the U.S., which means it’s in more of your diet than you might think. The main sources to watch for:
- Enriched bread and rolls, including sandwich bread, hamburger buns, and bagels
- Enriched pasta, both dried and fresh varieties made with enriched flour
- White rice labeled “enriched”
- Enriched flour and cornmeal, which means most baked goods, tortillas, and tamales made with corn masa flour
- Fortified breakfast cereals, some of which contain 100% of the daily value in a single serving
You don’t need to eliminate grains entirely. The key is choosing non-enriched alternatives. Whole wheat flour, brown rice, oats, and products labeled “unbleached, unenriched” skip the added folic acid. Many European-style or artisan breads use unenriched flour. Breakfast cereals vary widely, so check the nutrition label for “folic acid” in the ingredients list.
Natural food folate from vegetables, beans, and fruit is much less of a concern. Your body absorbs natural folate at a lower rate than synthetic folic acid, and it’s processed through different metabolic pathways. You don’t need to avoid spinach or lentils.
The Problem With Unmetabolized Folic Acid
Your body converts folic acid into its usable form through a multi-step process. But this conversion has a speed limit. When you take in more folic acid than your enzymes can handle, the unconverted portion circulates in your blood as unmetabolized folic acid, or UMFA. This doesn’t happen with natural food folate, which primarily circulates as a different, already-active form called 5-methyltetrahydrofolate.
The health implications of UMFA are still debated. Some research has linked high levels to increased risks of allergic disease, metabolic problems, and certain cancers. Other studies have found no clear harm. The proposed mechanism involves UMFA breaking down into a compound that may interfere with a specific subset of immune cells involved in mucosal immunity and cancer surveillance. But this research is preliminary, and the evidence isn’t settled in either direction.
What is clear: UMFA is a distinctly modern problem created by synthetic folic acid, not by folate from food. Some researchers have argued that replacing folic acid with 5-methyltetrahydrofolate in fortified foods would eliminate UMFA entirely while still preventing neural tube defects. Some supplement manufacturers already offer this alternative form, often listed as “methylfolate” or “5-MTHF” on labels. If you still want or need supplemental folate but are concerned about UMFA, switching to a methylfolate supplement is one option.
The B12 Connection
One of the most important reasons to pay attention to high folate involves vitamin B12. These two vitamins are deeply intertwined, and an imbalance between them can cause real harm.
Both folate and B12 deficiency cause the same type of anemia: your red blood cells become abnormally large and fewer in number, leading to fatigue and weakness. When someone is deficient in B12, the deficiency essentially traps folate in a form the body can’t use, creating a “functional” folate deficiency that produces anemia. But if you flood the system with extra folic acid, it bypasses that trap through an alternative pathway, restoring normal blood cell production. The anemia resolves, and everything looks fine on a standard blood test.
The problem is that B12 does something folate cannot: it protects your nervous system. When high folic acid intake masks B12 deficiency by correcting the anemia, the neurological damage from B12 deficiency continues silently. This was first documented in pernicious anemia patients in the 1950s who were treated with high-dose folic acid. Their blood counts improved, but they developed or worsened nerve damage because the underlying B12 deficiency went unrecognized.
If your folate is high and your B12 is low or borderline, this masking effect is a genuine risk. Getting your B12 level checked alongside folate is essential before assuming high folate is the only issue worth addressing.
MTHFR Variants and Folate Processing
Some people have genetic variations that affect how efficiently their body converts folic acid into its active form. The most common are variants in the MTHFR gene, which reduces the enzyme responsible for this conversion. People with these variants may have higher circulating levels of unconverted folic acid and lower levels of the active form their cells actually need.
If you have a known MTHFR variant and your serum folate appears high, the number on your blood test may be misleading. Your total folate could look elevated while your body is functionally short on the form it can use. In this situation, the goal isn’t necessarily to lower total folate but to shift the type of folate you’re consuming. Switching from folic acid supplements to methylfolate (5-MTHF) bypasses the impaired conversion step and delivers the active form directly.
What to Expect After Making Changes
Once you’ve stopped folic acid supplements and reduced fortified foods, give your body time. Serum folate (the level in your blood plasma) drops within days to weeks, but red blood cell folate, which reflects your long-term stores, takes several months to meaningfully decline. Plan to recheck your levels at three to six months to see where you stand.
A normal serum folate level is above 4 ng/mL (or 9.1 nmol/L). There isn’t a widely agreed-upon upper limit in standard reference ranges, which is part of why “high folate” can feel vague. The concern is less about a specific number and more about the source. High folate from synthetic folic acid, especially with detectable UMFA, is treated differently than high folate from eating a lot of broccoli and beans.
If your levels remain stubbornly high despite dietary changes and stopping supplements, that’s worth investigating further. Conditions like pernicious anemia or bacterial overgrowth in the small intestine can independently raise folate levels, and those require their own treatment rather than just dietary adjustment.