Vitamin B9 (folate) is an essential vitamin that helps your body form red blood cells and DNA, which are the building blocks of your body. It’s especially important for healthy growth and development during pregnancy.
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A wide range of foods contains folate or added (fortified) folic acid, but it can still be hard to get adequate B9. Folate deficiency, which is fairly common, can lead to serious complications like birth defects and anemia. In some cases, your healthcare provider may recommend a nutritional supplement.
“Vitamin B9 levels can be difficult to maintain, so it’s important to know what foods you can turn to for to better meet your needs,” says dietitian Julia Zumpano, RD. “And if you’re pregnant, folic acid supplements are always necessary for the health and wellbeing of the fetus.”
What is vitamin B9?
Vitamin B9 is one of eight B (B-complex) vitamins that help your body change food (carbohydrates) into fuel (glucose) to produce energy. You need B9 for the health of your liver, skin, hair and eyes, and to keep your nervous system working properly.
This essential nutrient is water-soluble (meaning it dissolves in water). It breaks down quickly in your body, and any excess leaves in your urine or stool.
The good news is, this means it’s less likely to reach toxic (dangerous) levels in your body. (But do be aware that it’s possible to consume too much folic acid, which can be harmful to your body over time.)
The bad news is, this can make it harder for you to maintain enough B9 in your body, and meet the recommended daily amount without taking supplements.
Zumpano reassures, “Upping your consumption is possible if you know what to look for, and can be easier than you expect.”
Folate vs. folic acid
The terms folate and folic acid are often used interchangeably, but are actually different forms of vitamin B9. The three main types are:
- Folate occurs naturally in food and refers to all forms of vitamin B9, including folic acid.
- Folic acid is a synthetic (artificial) form of B9 that’s found in supplements and fortified foods. In 1998, the U.S. required that folic acid be added to certain grains (rice, bread, pasta and some cereals) to ensure adequate public intake. Your body needs to change (convert) folic acid into another form of folate before it can be used for nutrition.
- Methylfolate (5-MTHF) is a natural, easier-to-digest form of vitamin B9 supplement than folic acid. Your body can immediately use this type of folate.
What is the function of vitamin B9?
Vitamin B9 helps your body make healthy new cells, supporting many of its functions, and may help prevent health issues from developing. It’s proven critical for reproductive health, too.
“It’s essential for people who are pregnant to take folic acid supplements to support healthy fetal growth and development,” notes Zumpano. “When you’re trying to conceive or are pregnant, it’s extremely difficult to get the amount of vitamin B9 needed.”
Studies show that people who take folic acid supplements before conception and during the first trimester of pregnancy may reduce their risk of having children with neural tube defects (birth defects of the brain and spine such as spina bifida) by 40% to 80%. Early evidence suggests folic acid may also be associated with a lower risk of autism, severe language delays and emotional issues.
Other research hints at even broader vitamin B9 benefits, from preventing or treating depression and memory loss to high blood pressure and cardiovascular disease. But more studies are needed to confirm these connections. For example, B9 may:
Promote heart health
Healthcare providers may prescribe B9 to lower high blood levels of homocysteine, a chemical that builds proteins (amino acids) that can harden your arteries. Both high and low levels of homocysteine (compared with moderate levels) have been associated with an increased risk of death from cardiovascular disease. But the exact link between folic acid and heart disease remains unclear.
Taking folic acid supplements may improve memory and thinking skills in older adults who experience faster-than-normal decline. One study also suggested a possible link between folate deficiency and an increased risk of Alzheimer’s disease.
Slow liver disease
Nonalcoholic steatohepatitis (NASH), an aggressive form of fatty liver disease, can cause severe liver damage. A recent study found that eating a combination of foods containing B12 and folic acid slowed disease progression and reversed liver fibrosis (thickening of scar tissue) and swelling (inflammation).
Slow age-related hearing loss
One study suggests folic acid supplements may help slow age-related hearing loss in older adults with low folate in their diet and high homocysteine levels.
Reduce risk of age-related macular degeneration (AMD)
The exact connection between folic acid and AMD, a condition that can cause vision loss, is unclear. But one large study found that women who took daily supplements of folic acid and vitamins B6 and B12 had a reduced risk of developing this eye disease.
What are vitamin B foods?
Folate occurs naturally in a wide variety of foods that you can add to your daily diet. These include:
- Beans and peas, including black-eyed peas, lentils, chickpeas and kidney beans.
- Beef and chicken liver.
- Dark, leafy green vegetables, such as spinach, asparagus, Brussels sprouts and beets.
- Fruit (and fruit juice), including avocados, tomato juice, oranges and orange juice, and melons.
- Nuts, such as walnuts and peanuts.
- Eggs and dairy.
- Seafood, including Dungeness crab and halibut.
- Meat and poultry, including chicken.
The U.S. Department of Agriculture (USDA) requires that folic acid be added to certain foods when they’re made. Foods fortified with folic acid include:
How much vitamin B9 per day do I need?
On nutrition labels, folate is shown as mcg (micrograms) of dietary folate equivalents (DFE), with folic acid (also in mcg) in parentheses below it. Your recommended vitamin B9 intake is:
|Age||Recommended Daily Amount|
|6 to 11 months*||80 mcg|
|1 to 3 years||150 mcg|
|4 to 18 years||200–400 mcg|
|Over 18 years||400 mcg|
|14+ years and pregnant||600 mcg|
|14+ years and lactating||500 mcg|
Source: 2020-2025 Dietary Guidelines for Americans
Do I need to take vitamin B9 supplements?
Most multivitamin or mineral supplements contain folic acid, especially prenatal vitamins for people who are pregnant or planning to conceive.
You don’t need to take supplements if you’re getting enough of what you need from food. But if you suspect you may lack vitamin B9, talk with a healthcare provider. A blood test can typically confirm if you have a deficiency.
“Vitamin B9, in all its forms, is important to maintain your health, and keep your body working well,” says Zumpano. “And with a little effort, you can get enough of it from the foods you’re used to eating and new foods that can be interesting and fun to explore.”