Folate vs. folic acid: what’s the difference?

last updated: Nov 18, 2021

3 min read

The terms folate and folic acid are often used interchangeably because they’re both types of vitamin B9. While there are distinct differences between the two, there is a lot of conflicting information about the different forms of folic acid that creates confusion.

Both have similar functions in the body, but they come from different sources and may be used differently. This article covers what both types are and how to get enough vitamin B9.  

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What is folate?

Folate is the form of vitamin B9 that occurs naturally in foods. Several different types of folate can be found in various foods or used in supplements, including (Golja, 2020):

  • Dihydrofolate (DHF)

  • Tetrahydrofolate (THF)

  • 5, 10-methylenetetrahydrofolate (5, 10-MTHF)

  • 5-methyltetrahydrofolate (5-MTHF)

  • L-methylfolate

Not all forms of folate are ready to use as soon as they’re absorbed into the body. Many types need to be converted into an active form before use. Methylfolate is the most active form of folate and easier for the body to use quickly (Roffman, 2018).

While folate can be used in supplements, it’s naturally found in foods like:

  • Brussels sprouts

  • Green leafy vegetables, like cabbage, kale, spinach, arugula

  • Beans and legumes, like chickpeas, kidney beans, peas

  • Animal livers (though you should avoid these during pregnancy)

  • Citrus fruits, like oranges, mangos, kiwis

  • Bananas

  • Asparagus 

  • Avocados

What is folic acid?

Folic acid is a synthetic form of vitamin B9. It’s considered a type of folate, but the difference is that it isn’t found naturally in food. 

Food manufacturers started using folic acid during processing after researchers found the connection between low folate and neural tube defects. A vitamin B9 deficiency increases the risk for problems with neural tube development during the first trimester of pregnancy (Khan, 2021). 

Some food products are fortified with folic acid, meaning folic acid is added to the food during processing. Here are some of the fortified foods that may have folic acid added:

  • Enriched grains and flours

  • Bread, pasta, rice, and cornmeal

  • Fortified breakfast cereals and oatmeal

However, not everyone can efficiently use folic acid because it isn’t an active form of vitamin B9. 

Sometimes, the body isn’t able to effectively convert folic acid into a usable form, and unmetabolized folic acid could build up in the bloodstream. For example, people with an MTHFR gene mutation may have more trouble converting folic acid into an active form (Golja, 2020).

Signs of a folate deficiency

Vitamin B9 helps the body to make and repair DNA as well as produce red blood cells. If you don’t get enough natural folate through foods or vitamin supplements, you will likely develop a folate deficiency. Signs and symptoms of a folic acid deficiency include (Khan, 2021):

  • Fatigue

  • Gray hair

  • Mouth sores

  • Stunted growth

  • Tongue swelling

  • Depression

  • Irritability

  • Insomnia

  • Increased risk of birth defects in pregnant women, such as neural tube defects (spina bifida and anencephaly)

  • Increased risk of anemia (low red blood cells)

Who should take folate and folic acid supplements?

It’s best to focus on consuming dietary folate from whole foods, like folate-containing fruits and vegetables. However, it’s common for people to have difficulty getting enough folate through their diet alone.

For anyone with signs of a deficiency, a supplement can help return folate to normal levels. A dietary supplement may be beneficial for women of childbearing age because a neural tube defect can develop before most women are aware they’re pregnant. 

Talk with your healthcare provider about the right multivitamin or prenatal vitamin if you’re planning to become pregnant, are early in your pregnancy, or breastfeeding. 

How much vitamin B9 do you need daily?

The recommended daily intake of folate is about 400 micrograms (mcg) per day for most adults. 

In some cases, your healthcare provider may recommend larger doses of folic acid if you have a deficiency. They may recommend amounts between 1 and 5 milligrams (mg) or 1,000 to 5,000 mcg of folic acid per day (Khan, 2021). 

If you have known problems converting folic acid or are unsure, consider taking a supplement with folate instead of a folic acid supplement. Discuss with your healthcare provider which option is best for you. 

Side effects of folic acid supplements

Vitamin B9 is one of the water-soluble vitamins. This means that extra amounts of folate are filtered out of the bloodstream by the kidneys and removed through your urine, so it’s rare to experience toxicity with this type of vitamin.

Still, some research suggests increased folic acid intake may lead to some side effects: 

  • Undetected vitamin B12 deficiency: High doses of folic acid supplements may mask anemia caused by a vitamin B12 deficiency and increase the risk of nervous system problems caused by a chronic vitamin B12 deficiency (Golja, 2020) 

  • Increased cancer risk: A 2017 study found an association between high folate levels in the bloodstream and the risk of colorectal cancer (Rees, 2017). More research is needed to confirm this and understand if there are any direct effects of folic acid on cancer risk.

  • Altered folate metabolism: Early research suggests high doses of folic acid may decrease the production of the enzymes and transporters for folate. Over time, this may lead to higher amounts of unmetabolized folic acid in the bloodstream (Tam, 2012).

DISCLAIMER

If you have any medical questions or concerns, please talk to your healthcare provider. The articles on Health Guide are underpinned by peer-reviewed research and information drawn from medical societies and governmental agencies. However, they are not a substitute for professional medical advice, diagnosis, or treatment.

  • Crider, K. S., Bailey, L. B., & Berry, R. J. (2011). Folic acid food fortification-its history, effect, concerns, and future directions. Nutrients , 3 (3), 370–384. doi: 10.3390/nu3030370. Retrieved from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3257747/

  • Golja, MV., Šmid, A., Karas Kuželički, N., Trontelj, J., Geršak, K., & Mlinarič-Raščan, I. (2020). Folate insufficiency due to MTHFR deficiency is bypassed by 5-methyltetrahydrofolate. Journal of Clinical Medicine , 9 (9), 2836. doi: 10.3390/jcm9092836. Retrieved from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7564482/

  • Khan KM, Jialal I. (2021). Folic Acid Deficiency. [Updated 2021 Sep 28]. In: StatPearls [Internet]. Retrieved November 1, 2021 from https://www.ncbi.nlm.nih.gov/books/NBK535377/

  • Rees, J. R., Morris, C. B., Peacock, J. L., Ueland, P. M., Barry, E. L., McKeown-Eyssen, G. E., et al. (2017). Unmetabolized folic acid, tetrahydrofolate, and colorectal adenoma risk. Cancer Prevention Research , 10 (8), 451–458. doi: 10.1158/1940-6207.CAPR-16-0278. Retrieved from https://pubmed.ncbi.nlm.nih.gov/28600398/

  • Roffman, J. L., Petruzzi, L. J., Tanner, A. S., Brown, H. E., Eryilmaz, H., Ho, N. F., et al. (2018). Biochemical, physiological and clinical effects of l-methylfolate in schizophrenia: a randomized controlled trial. Molecular Psychiatry , 23 (2), 316–322. doi: 10.1038/mp.2017.41. Retrieved from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5599314/

  • Tam, C., O'Connor, D., & Koren, G. (2012). Circulating unmetabolized folic acid: relationship to folate status and effect of supplementation. Obstetrics and Gynecology International , 2012 , 485179. doi: 10.1155/2012/485179. Retrieved from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3317000/


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Every article on Health Guide goes through rigorous fact-checking by our team of medical reviewers. Our reviewers are trained medical professionals who ensure each article contains the most up-to-date information, and that medical details have been correctly interpreted by the writer.

Current version

November 18, 2021

Written by

Ashley Braun, RD, MPH

Fact checked by

Steve Silvestro, MD


About the medical reviewer

Dr. Steve Silvestro is a board-certified pediatrician and Associate Director, Clinical Content & Education at Ro.