Folate (vitamin B9): Foods, Deficiency Symptoms, Benefits, And More

Có thể bạn quan tâm

Medical News TodaySubscribeWhat foods are high in folate, and what are its benefits?

Medically reviewed by Grant Tinsley, Ph.D., CSCS,*D, CISSN — Written by Caitlin Geng — Updated on November 29, 2023

Foods high in folate
Deficiency
Folic acid vs. folate
Recommended intake
Benefits
Risks
Summary

Folate is present in a wide range of foods, like beef liver and beans. Many other foods are also fortified with folic acid, which is a synthetic form of folate. A person’s body requires folate to make DNA and other genetic material.

Folate is an essential B vitamin necessary for producing red and white blood cells in bone marrow, producing DNA and RNA, and transforming carbohydrates into energy. Having an adequate amount of folate is especially important during periods of rapid growth, such as pregnancy, infancy, and adolescence.

In this article, we look at foods high in folate, the symptoms of folate deficiency, the differences between folic acid and folate, and the recommended intake. We also look at folate’s health benefits and potential risks.

Foods high in folate

A close-up of large, dark green kale leaves, which are a source of folate. — Enrique Díaz/7cero/Getty Images

Folate, or vitamin B9, occurs naturally in a variety of foods. Sometimes, manufacturers fortify foods with folate’s synthetic form — folic acid.

The richest naturally occurring sources of folate include:

beef liver
vegetables, especially Brussels sprouts, dark leafy greens, and asparagus
fruits and fruit juices, especially oranges and orange juice
beans, peas, and nuts, such as kidney beans, black-eyed peas, and peanuts

Foods that companies often fortify with folic acid include:

fortified corn masa flour, which is used to make tortillas and tamales
fortified cereals
enriched bread flour, pasta, rice, and cornmeal

The body’s ability to absorb and use folate varies from one food to another and is difficult to measure. There are also many forms of folate, and some break down during cooking or processing.

Folate deficiency symptoms

Folate deficiency can cause a wide range of symptoms. These may include:

muscle weakness
problems with judgment, memory, and understanding
fatigue
paresthesia, or pins and needles
a red, sore tongue
ulcers in the mouth
vision problems
depression and confusion

Because folate deficiencies usually occur alongside other nutritional deficiencies, such as B12 or iron deficiency, people may also have symptoms of these other conditions.

Most people in the United States get enough folate, but some are more at risk of not getting enough. These include people with:

alcohol use disorder
a mutation in the MTHFR gene, which impairs the conversion of folate into its active form so the body can use it
conditions that interfere with nutrient absorption, such as inflammatory bowel disease or celiac disease
eating disorders

Folate deficiency is more common among females, affecting around 19% of female adolescents ages 14–19 years and 17% of female adults ages 19–30 years. The rate among non-Hispanic Black females is higher, at 23%.

At present, researchers are not sure why folate levels are lower among Black females, but some believe it is due to social determinants of health, such as the availability of fresh food or difficulty accessing healthcare.

Folic acid vs. folate

Folate is a form of vitamin B9, and it occurs naturally in various foods. Folic acid is also a form of vitamin B9, but it does not occur naturally in food. Companies add folic acid to foods to make them more nutritious. Both types are nutritionally valuable, and most people have no trouble absorbing either form.

Companies use folic acid in foods because, unlike folate, it remains stable when exposed to heat and light. This makes it ideal for adding to foods people cook, such as bread.

According to the Centers for Disease Control and Prevention (CDC), folic acid is the only form of vitamin B9 that is proven to reduce the risk of neural tube defects in fetuses. For this reason, people who are pregnant or trying to conceive should take 400 micrograms (mcg) of folic acid per day.

Folic acid and the MTHFR gene

Some people have a polymorphism in the MTHFR gene. That means this gene contains a mutation that reduces how effectively the body converts folic acid or folate into its active form, methylfolate. The body needs to be able to do this in order to make full use of this nutrient.

MTHFR gene polymorphisms affect:

25% of Hispanic people
10% of white and Asian people
1% of African Americans

Despite having a reduced ability to convert folic acid and folate into their active form, people with these polymorphisms can still consume either nutrient safely. People who are pregnant and have an MTHFR gene polymorphism should still take the recommended amount of folic acid.

Some people with this genetic difference may find it beneficial to take supplements that contain methylfolate itself, so the body does not have to convert it. However, studies on how effective this is have been inconclusive.

Recommended intake of folate

The recommended daily allowance (RDA) of folate differs depending on age. The RDA for various ages are as follows:

0–6 months: 65 mcg
7–12 months: 80 mcg
1–3 years: 150 mcg
4–8 years: 200 mcg
9–13 years: 300 mcg
14 years and older: 400 mcg
during pregnancy: 600 mcg
during lactation: 500 mcg

Benefits of folate

Folate is necessary for many bodily functions. Its health benefits include:

Lower risk of neural tube defects

An adequate amount of folic acid is essential during pregnancy to help prevent neural tube defects. This issue occurs when the neural tube, which forms the early brain and spinal cord, does not close properly. This happens in early pregnancy and can result in conditions such as spina bifida or anencephaly.

Lower risk of stroke

According to the National Institutes of Health (NIH), researchers have found that folic acid supplements lower levels of the amino acid homocysteine. High levels of this amino acid are linked to a higher risk of cardiovascular disease and stroke.

While studies have not proven that folic acid reduces the risk of cardiovascular disease, several have found that higher intake is associated with a lower risk of stroke.

Possible reduced risk of cognitive decline

Homocysteine is also associated with a higher risk of dementia. While studies have not shown that taking folic acid reduces the risk of dementia in otherwise healthy people, those who are at risk of cognitive decline in older age may benefit from taking it. Evidence suggests that it may help preserve memory and executive function in at-risk groups.

Folate and cancer

Research on the link between folate and cancer has produced varied results. Some studies, such as one from 2017, suggest that folate may offer protection against certain cancers. Low folate levels are associated with an increased risk of certain cancers, such as lung, breast, cervical, and stomach cancers.

However, other studies have not found an association between the vitamin and cancer.

Further resources

For more in-depth resources about vitamins, minerals, and supplements, visit our dedicated hub.

Does folate have risks?

In moderate amounts, folate is not dangerous to most people. However, in large amounts, folate may pose certain health risks. Depending on the situation, this could include:

Masking vitamin B12 deficiency: People with vitamin B12 deficiency may develop megaloblastic anemia, which can cause neurological damage if left untreated. As folate can help treat certain symptoms of anemia, but not the neurological damage it can cause, folate could mask symptoms until the consequences of the true deficiency become irreversible.
Preneoplastic lesions: These lesions consist of altered cells that are more likely to become cancerous than regular cells. High folic acid intake has been linked to faster progression of these cells, which may increase the risk of certain cancers, such as colorectal cancer.
Unmetabolized acid: If a person has more folic acid than the body can metabolize and transform, it could affect the immune system. Some scientists have also suggested there may be a link between unmetabolized folic acid and cognitive impairment in older adults. However, there is not much research on this, so the risk is unknown.
Medication interaction: Folate supplements may interact badly with various medications, including epilepsy medications, methotrexate, and sulfasalazine.

Before taking any dietary supplement, it is important to speak with a doctor to check that it is safe and there are no other deficiencies or conditions that need to be addressed.

Summary

Folate is a naturally occurring form of vitamin B9, which people get from their food. Dark leafy greens, beef liver, and oranges are all good sources of folate. People can also get another form of B9, folic acid, from fortified foods. Some common examples include cereals, breads, and pasta.

Most people get enough folate from a balanced diet, but others may need extra help getting enough. A folate deficiency can cause fatigue, mouth ulcers, and a low mood. It is more common in females and those with conditions that affect folate absorption.

If someone is concerned they may have a nutritional deficiency or are trying to conceive, they should speak with a doctor.

Supplements
Nutrition / Diet
Pregnancy / Obstetrics
Complementary Medicine / Alternative Medicine

How we reviewed this article:

SourcesMedical News Today has strict sourcing guidelines and relies on peer-reviewed studies, academic research institutions, and medical journals and associations. We only use quality, credible sources to ensure content accuracy and integrity. You can learn more about how we ensure our content is accurate and current by reading our editorial policy.

Dong, H., et al. (2015). Efficacy of supplementation with B vitamins for stroke prevention: A network meta-analysis of randomized controlled trials.https://www.ncbi.nlm.nih.gov/pubmed/26355679
Folate fact sheet for consumers. (2021).https://ods.od.nih.gov/factsheets/Folate-Consumer/
Folate fact sheet for health professionals. (2021).https://ods.od.nih.gov/factsheets/Folate-HealthProfessional/
Folic acid safety, interactions, and effects on other outcomes. (2017).https://www.cdc.gov/ncbddd/folicacid/faqs/faqs-safety.html
General information about NTDs, folic acid, and folate. (2021).https://www.cdc.gov/ncbddd/folicacid/faqs/faqs-general-info.html
Gonzalez-Velez, M., et al. (2020). Racial/ethnic differences in patients with anemia and folate deficiency [Abstract].https://onlinelibrary.wiley.com/doi/abs/10.1111/ijlh.13205
Henry, C. J., et al. (2017). Folate dietary insufficiency and folic acid supplementation similarly impair metabolism and compromise hematopoiesis.https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5709097/
MTHFR gene, folic acid, and preventing neural tube defects. (2020).https://www.cdc.gov/ncbddd/folicacid/mthfr-gene-and-folic-acid.html
Overview: Vitamin B12 or folate deficiency anaemia. (2019).https://www.nhs.uk/conditions/vitamin-b12-or-folate-deficiency-anaemia/
Tomita, L. Y. (2016). Folate and cancer: Is there any association?http://journals.sagepub.com/doi/abs/10.1177/2326409816661357
Zhao, Y., et al. (2017). Folate intake, serum folate levels and esophageal cancer risk: An overall and dose-response meta-analysis.https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5354672/

Share this article

Medically reviewed by Grant Tinsley, Ph.D., CSCS,*D, CISSN — Written by Caitlin Geng — Updated on November 29, 2023

Latest news

Sleep quality may increase dementia risk: Latest evidence
B12 from diet vs supplements: Which is better for heart health, immunity?
'Dry January': 1 month of no alcohol makes real difference to health, study confirms
7 heart-healthy behaviors may help increase longevity after cancer
Dancing, reading, and video games could help delay brain aging

Related Coverage

What to know about folic acidMedically reviewed by Jillian Kubala, MS, RD
Folic acid is the synthetic form of folate, an important B vitamin. Learn about its functions, recommended intake, and side effects here.
READ MORE
What to know about folate deficiencyMedically reviewed by Debra Sullivan, Ph.D., MSN, R.N., CNE, COI
Folate is an essential nutrient. A lack of dietary folate can cause anemia. Learn about the causes, symptoms, treatment, and prevention of folate…
READ MORE
Are there benefits to taking prenatal vitamins while not pregnant?
Benefits of prenatal vitamins while not pregnant includes supporting iron levels in people and providing folic acid for preconception planning. Read…
READ MORE

Từ khóa » Vit B9 Dosage

Health Conditions

Health Products

News

Original Series

Podcasts

General Health

Health Tools

Quizzes

About Medical News Today

Find Community

Follow Us