The terms folic acid and folic acid are often used interchangeably. However, even though both are forms of vitamin B9, the two compounds are quite different.
While folic acid is naturally found in a variety of whole foods, folic acid is a synthetic form commonly found in fortified foods and supplements.
This article explains the difference between folic acid and folic acid, as well as their sources, benefits and potential risks.
Folate is an umbrella term used to describe all forms of vitamin B9 that contain folic acid.
Natural folic acid is a form of vitamin B9 found primarily in dark leafy greens, citrus fruits, and legumes.
Folic acid is a synthetic (artificial) folate found in dietary supplements and fortified foods such as breakfast cereals, rice, pasta, and bread.
The body absorbs folic acid more efficiently compared to the natural folic acid found in food. About 85% of folic acid from supplements and fortified foods is absorbed, whereas only 50% of natural folic acid is absorbed.
The recommended dietary intake (RDA) for folic acid is based on dietary folate equivalents (DFE). This unit of measurement was developed to take into account the increased absorption of supplemental folic acid.
One microgram (mcg) DFE is equivalent to:
- 1 mcg folate naturally found in food
- 0.6 mcg of folic acid from fortified foods or dietary supplements taken with food
- 0.5 mcg folic acid from dietary supplements taken on an empty stomach
The amount of folic acid you need depends on your age and gender. The RDA for folic acid in DFE is:
- Up to 6 months of age: 65 μg
- For ages 7-12 months: 80 μg
- 1 to 3 years old: 150 μg
- 4 to 8 years old: 200 μg
- 9 to 13 years old: 300 μg
- Adults and youth over the age of 14: 400 μg
- Pregnant adults and teens: 600 μg
- Lactating adults and teens: 500 μg
Folic acid helps the body make new, healthy red and white blood cells. It also helps in the production of DNA.
Since folic acid is a water-soluble vitamin, it is not stored in the body and must be replenished regularly. Thus, inadequate dietary intake of folate can lead to low blood folate levels in just a few weeks.
Not getting enough folate can lead to folate deficiency anemia, a blood disorder that causes fatigue, weakness, difficulty concentrating, shortness of breath, and irritability.
Folic acid is especially important during pregnancy as it helps prevent miscarriages and protects babies from birth defects. In particular, folic acid protects against neural tube defects, serious birth defects of the brain and spine in babies.
To reduce the risk of neural tube defects, it is recommended that all women of reproductive age consume 400 mcg of folic acid per day. This can be met by eating a healthy diet that includes naturally occurring folic acid from food, as well as fortifying foods, supplements, or a combination of both.
It is important to note that supplements containing folic acid in forms other than folic acid, such as 5-methyltetrahydrofolate (5-MTHF), have not proven effective in preventing neural tube defects.
Other groups at risk for folic acid deficiency include people with the following conditions:
- Alcohol Use Disorder: Alcoholics often have poor diets and inadequate folic acid intake. In addition, alcohol interferes with folic acid absorption and increases folic acid excretion, further increasing the risk of deficiency.
- Malabsorption disorders: People with celiac disease, inflammatory bowel disease (IBS), and atrophic gastritis (chronic gastritis) may not absorb as much folic acid as people without these disorders. Folic acid deficiency is also common after weight loss surgery.
- MTHFR polymorphism: People with the MTHFR C677T gene mutation have a reduced ability to convert folic acid into one of its active forms, 5-MTHF. Some people with this genetic mutation may benefit from supplementation with 5-MTHF (the active form of folic acid). However, due to limited research, even an individual with the MTHFR C677T gene mutation should not substitute her 5-MTHF for folic acid before or during pregnancy.
Some of the richest natural sources of folic acid include:
In 1998, the U.S. Food and Drug Administration mandated the addition of folic acid to fortified grain products to reduce the risk of neural tube defects during pregnancy.
Foods commonly fortified with folic acid include:
- breakfast cereal
- bread
- flour
- cornmeal
- pasta
- white rice
- Products made from a type of flour called corn masa, such as tortilla chips, taco shells, and tortillas
If you’re unsure if a food is fortified with folic acid, look for the words “fortified” or “fortified” on the food label. The amount of folate and folate in mcg DFE per serving is listed on the Nutrition Facts label.
Folic acid found naturally in foods and beverages is safe. Folic acid is also safe for most healthy adults and children. However, it’s not for everyone.
Talk to your healthcare provider before taking folic acid if:
- have a history of allergic reactions to folic acid or other drugs
- Are undergoing dialysis, a treatment for kidney failure that filters excess water and waste products from the blood
- low vitamin B12 levels
- Having cancer without a definitive diagnosis of folate-deficiency anemia
- put in a heart stent
Always consult your healthcare provider before taking any dietary supplements or making any major changes to your diet.
Additionally, avoid taking more than the daily limit for folic acid from dietary supplements or fortified foods unless directed by a healthcare professional.
The maximum daily intake of folic acid from supplements and fortified foods is:
- From birth to 12 months: not established
- 1 to 3 years old: 300 μg
- 4 to 8 years old: 400 μg
- 9 to 13 years old: 600 μg
- 14 to 18 years old: 800 μg
- Adults 19+: 1,000 μg
Taking high-dose folic acid supplements can mask vitamin B12 deficiency, delay treatment and can cause permanent damage to the brain and nervous system. There is some evidence that it may also increase the risk of certain types of cancer, such as colorectal cancer, in some people.
Additionally, taking too much folic acid can prevent the body from processing or metabolizing it completely, allowing unmetabolized folic acid to accumulate in the bloodstream. This is believed to be associated with changes in the immune system and cognitive impairment in older people. However, further studies are needed to fully understand these effects.
Higher doses of folic acid may be recommended under medical supervision in certain circumstances.
For example, people at high risk of having a baby with a neural tube defect are often advised to take 4,000 mcg of folic acid daily for the first three months up to the 12th week of pregnancy.
High-risk individuals include those with a history of neural tube defects or those whose partners or children are affected by neural tube defects.
drug interactions
Folic acid may interact with the following drugs:
- methotrexate: Folic acid can interfere with methotrexate (rheumatrex, trexol) when taken as a cancer treatment.
- Antiseizure drugs: Folic acid can lower blood levels of phenytoin (dilantin), carbamazepine (carbatrol, tegretol, equator, epitol), and valproic acid (depacone). These drugs can also lower blood folic acid levels.
- Sulfasalazine: Taking sulfasalazine (azulfidine) for ulcerative colitis can prevent the body from absorbing folate effectively, resulting in folate deficiency.
If you are taking any medicines or dietary supplements, consult your pharmacist or health care provider to make sure no interactions exist.
Folic acid is a generic term used to describe all forms of vitamin B9. Folic acid is found naturally in many foods, including leafy greens, beans, and citrus fruits. Folic acid, on the other hand, is a synthetic form that is added to fortified foods and used in the manufacture of dietary supplements.
Getting enough folic acid is especially important during pregnancy to prevent birth defects and miscarriage.
Folate from whole foods is considered safe. However, taking large amounts of folic acid supplements can have negative effects on your health. Always take folic acid supplements as recommended by your healthcare provider to avoid potential side effects.
