Folic Acid: Can Too Much of a Good Thing Be Bad?

Delve into the multifaceted world of folic acid, gaining insights into its essential role in cell production, heart health, and the prevention of birth defects.

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By Staff Writer
Korana Braun | Content Editor | InsideTracker
Edited by Korana Braun

Published March 6, 2024.

a woman sitting in a chair eating a bowl of cereal rich in folic acid

From the recommended daily intake for different age groups to its impact on athletic performance, this post unravels the mysteries of folic acid and its far-reaching effects on our health and well-being. Discover the surprising facts about folic acid and how it influences our everyday lives.

What is folic acid?

Folic acid (also known as folate) is a water-soluble vitamin that, along with vitamin B12, belongs to the group of B-complex vitamins.

It’s an essential vitamin, meaning that our bodies can’t make it themselves, and it’s vital for the production of new cells (aka the building blocks of life). Some scientists also speculate that folic acid plays a role in maintaining heart health and preventing cell mutations that may lead to cancer.

How much folic acid do you need?

Adults, aged 19 and older, need about 400µg/day of folic acid.

In addition to helping grow the building blocks of life, folic acid plays another important role: it helps prevent birth defects in a baby’s brain and spine. Therefore, women of childbearing age can benefit from higher doses and should shoot for 600µg/day (and up to 800µg/day) at least one month before they plan to become pregnant.

Breastfeeding women should aim for at least 500µg/day. 

There are several other medical conditions that may increase folic acid needs, including anyone taking medications for epilepsy, Rheumatoid arthritis, lupus, psoriasis, asthma, and inflammatory bowel disease; anyone with kidney disease who is on dialysis; anyone with liver, sickle cell, or celiac diseases.

Consult with your primary care physician about taking a supplement if you suffer from one of these conditions.

Good sources of folate

Folic acid is found in a variety of food sources. Some of the highest sources include:

  • Beef
  • Liver
  • Lentils
  • Spinach
  • Enriched noodles
  • Great northern beans
  • Asparagus

Some people prefer to take supplements rather than relying on food sources to obtain folic acid. Most multivitamins sold in America contain the amount of folic acid women need each day. Women can also choose to take a supplement that has only folic acid in it if they’re not low in other nutrients to prevent overdosing on other vitamins or minerals.

A federal law passed in 1996 necessitated the fortification of enriched bread, cereals, flours, corn meals, pasta, rice, and other grain products with folic acid to prevent birth defects in women who weren’t consuming adequate amounts of the vitamin in their typical diet.

Now, consuming a bowl of fortified breakfast cereal can get most people to meet their recommended daily intake. Use your InsideTracker food basket to find food sources of folate that agree with your taste buds.

What do high folate levels mean?

Folic acid is readily available in naturally-occurring food sources, fortified grains, and multivitamins, which some Americans take as an added insurance even when they already consume adequate amounts in their diet. This leads to overconsumption of the vitamin for some. In fact, in a pilot study conducted by Segterra scientists, half of all subjects had high blood levels of folate.

This can lead to several negative outcomes. Large amounts of folic acid can mask the damaging effects of vitamin B12 deficiency by correcting the megaloblastic anemia caused by vitamin B12 deficiency without correcting the neurological damage that also occurs.

There are indications that high serum folate levels might not only mask vitamin B12 deficiency but could also exacerbate the anemia and worsen the cognitive symptoms associated with vitamin B12 deficiency.

Folic acid FAQs

What causes high folate levels?

What medical conditions cause high folate levels?

What are the symptoms of high folate levels?

How to lower high folate levels?

What does it mean if the folate level is greater than 24?

What does high folate serum mean?

What is serum folate's normal range?

Athletes: Listen up!

Your body’s ability to grow and regenerate healthy red blood cells is especially important for athletes who need to build and restore healthy tissue after workouts to make their bodies stronger. Underconsuming folic acid can actually hinder athletic performance by reducing the amount of red blood cells available to deliver oxygen to your muscles. Chronic low folate intake can lead to fatigue and anemia.

The good news: Research shows you can actually increase your folic acid levels through exercise! Athletes who completed high-intensity interval training (HIT), such as 20 km/week of swimming with intervals of maximum intensity over 3 weeks, were able to raise the amount of folic acid in their blood.

And remember that supplementation can be safe and effective, as long as you know what your target folic acid level is and how far you are from your target. An InsideTracker analysis gives you the tools to measure and track your progress over time, helping you achieve your optimum serum folate levels and maximizing your potential for athletic excellence. 

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