Folic Acid: Everything You Need to Know

What’s the difference between folate and folic acid?

Although the terms “folate” and “folic acid” are often used interchangeably, they are actually different forms of the same vitamin: vitamin B9.

Folic acid has a different structure than folate and has slightly different effects in your body. “Folate” is the genericTrusted Source name that encompasses all forms of vitamin B9, including folic acid and 5-MTHF. Folic acid is a specific synthetic form of this vitamin.

You can find folate in plant and animal foods like theseTrusted Source:

• spinach
• kale
• broccoli
• avocado
• citrus fruits
• eggs
• beef liver

Folic acid is added to foods such as flour, ready-to-eat breakfast cereals, and breads.

It’s also in dietary supplements, such as multivitamins.

What does the body use folate for?

Your body uses folate to:

• make and repair DNA
• help cells grow, divide, and work properly
• produce certain proteins
• help red blood cells mature

Folate deficiency can lead to many health problems, includingTrusted Source:

• anemia
• an increased risk of heart disease and certain cancers
• developmental irregularities in infants if pregnant people don’t get enough folate

Many countries, including the United States, requireTrusted Source certain grain products to be fortified with folic acid. Folic acid fortification helps prevent neural tube irregularities in infants.

Benefits and uses

Both folic acid and folate are used in supplements. Although these two nutrients treat the same conditions, they are metabolized differently in the body and can affect health in different ways.

Here are some common uses and benefits of folic acid supplements.

Treating folate deficiency

Folate deficiency can happen for many reasons. Some possible causesTrusted Source of folate deficiency are:

• a lack of folate in your diet
• diseases or surgeries that affect how your body absorbs folate, including celiac disease, short bowel syndrome, and gastric bypass surgery
• no stomach acid (achlorhydria) or low stomach acid (hypochlorhydria)
• drugs that affect folate absorption, including methotrexate and sulfasalazine (Azulfadine)
• alcohol use disorder
• pregnancy
• hemolytic anemia
• dialysis

Consuming too little folate can cause complicationsTrusted Source such as anemia, fetal development issues, mental impairment, impaired immune function, and depression. Taking folic acid or folate supplements can bring up your levels and prevent these complications.

Preventing birth defects and pregnancy complications

Folic acid supplements can help to prevent neural tube irregularities, including spina bifida and anencephaly. Getting enough folic acid during pregnancy can reduceTrusted Source the chance that your baby will be born with one of these conditions.

Folic acid supplements not only help prevent fetal development issues but also help lower the risk of pregnancy complications such as preeclampsia.

Maintaining brain health

Low blood folate levels are linked to poor mental function and an increased risk of dementia. Even folate levels that are technically normal but on the low side might increase the risk of mental impairment in older adults.

Adequate folate intake may alsoTrusted Source help protect against Alzheimer’s disease.

In a 2019 studyTrusted Source in 180 adults with mild cognitive impairment, taking 400 mcg of folic acid supplements daily for 2 years improved measures of brain function and reduced blood levels of proteins that are involved in Alzheimer’s disease.

Another older 2016 study looked at 121 people with newly diagnosed Alzheimer’s disease who were being treated with the medication donepezil (Aricept).

Those who also took 1,250 mcg of folic acid per day for 6 months had improved thinking ability and less inflammation than those who took Aricept alone.

Treating mental health conditions

Folate is involved in the production of brain chemicals called neurotransmitters. Consuming too little folate has been linked to depression, schizophrenia, and other mental health conditions.

For example, people with depression may haveTrusted Source lower blood levels of folate than people without depression.

A 2022 review of studies suggests that folic acid and folate supplements may help reduce symptoms of mental health conditions such as postpartum depression, schizophrenia, and bipolar disorder.

Taking folate supplements in addition to antidepressant medication may reduce depression symptoms more than taking antidepressant medication alone.

A reviewTrusted Source of seven studies found that treatment with folate supplements plus antipsychotic medication may improve symptoms in people with schizophrenia more than antipsychotic medication alone.

However, larger, more robust studies are needed to further support these findings.

Reducing heart disease risk factors

Folate-based supplements, including folic acid, may helpTrusted Source improve heart health and reduce the risk of heart disease.

High levels of the amino acid homocysteine are thought to increase heart disease risk. Because folate helps break down homocysteine, low folate can lead to high homocysteine levels, also known as hyperhomocysteinemia.

Folic acid supplements can help bring downTrusted Source homocysteine levels and may lower heart disease risk.

Other possible benefits

Folic acid supplements may also help with these other health conditions:

• Diabetes. Folate supplements may help improve blood sugar regulation and reduce insulin resistance in people with diabetes. Because the diabetes drug metformin can lower folate levels, you may need a supplement if your levels are low.
• Fertility issues. Folate can improve egg quality and help eggs grow and implant in the uterus. Taking folate may increase the chance of getting pregnant and carrying a baby to term. People who use assisted reproductive technology to conceive may be more likely to have a baby if they have a higher intake of supplemental folate.
• Inflammation. Inflammation plays a role in many diseases. Folic acid and folate supplements have been shown to reduce markers of inflammation such as C-reactive protein.
• Kidney disease. The kidneys usually filter waste out of the blood, but when the kidneys are damaged, homocysteine can build up. About 85% of people with chronic kidney disease have too much homocysteine in their blood. Folic acid supplements may help reduce homocysteine levels and heart disease risk in people with kidney disease.

Larger studies are still needed to confirm the benefits of folate supplementation.

This list doesn’t include every possible benefit of folic acid. There are many other reasons people may use folate-based supplements.

Side effects and precautions

Eating folate-rich foods and taking natural forms of folate such as 5-MTHF are generally considered safe. But taking high doses of folic acid through supplements could potentially lead to a buildup of unmetabolized folic acid in your blood.

“Unmetabolized” means your body hasn’t broken down the folic acid or converted it into other forms of folate. No confirmed health risks due to unmetabolized folic acid have yet been found, but undiscovered risks may still exist.

It’s important to note that most children and adults in the United States get enoughTrusted Source folate from food and don’t need to take a folic acid supplement.

How to take 

Folate and folic acid can be found in many forms. They are added to multinutrient supplements, including multivitamins and B-complex vitamins. Most adult supplements contain 680–1,360 mcgTrusted Source DFE (400–800 mcg of folic acid).

The Tolerable Upper Intake Level (UL) is the highest daily folic acid dose you can take without experiencing harmful side effects.

The UL includes only folate from fortified foods and dietary supplements. High intake of naturally occurring folate from food has not been shown to cause any adverse effects.

The UL for folate in supplements and fortified foods is:

Most children in the United States get enough folate from food, and 30–66% of children ages 1–13 who take folic acid supplements exceed the UL for their age group. Ask a pediatrician before giving your child a folic acid supplement to make sure it’s safe.

You can take all forms of folic acid with or without food.

Before taking folic acid

A healthcare professional might recommend a folic acid supplement if you have a deficiency or you are pregnant or thinking about getting pregnant.

Let a healthcare professional know what other prescription and over-the-counter medications you take. Folic acid may interactTrusted Source with some medicines.

Storage and handling

Store folic acid supplements in a cool, dry place. Keep supplements away from humid areas, such as the bathroom.

Overdose

There’s no setTrusted Source upper limit for folate in foods. Because folate is water-soluble, your body removes any extra you consume. Still, it may be possible to develop side effects if you take folic acid supplements in amounts greater than the UL.

A healthcare professional may recommend higher doses if you have a folate deficiency. Avoid taking more than the UL unless a healthcare professional directs you to do so.