Folic acid is a water-soluble vitamin that is important for many functions in the body, such as maintaining good brain health and preventing cardiovascular disease and anemia. It also plays an important role in the development of the fetal nervous system.
Folic acid, also known as folate or vitamin B9, is found in a variety of foods like spinach, beef liver, and brewer's yeast. It also comes in supplement form.
Folic acid deficiency can cause symptoms like loss of appetite, diarrhea, and hair loss. Folic acid deficiency in pregnancy can also cause problems with fetal development in addition to complications like high blood pressure and premature birth.
Health benefits
Folic acid is necessary for:
1. Maintaining good brain health
Folic acid is important for brain health, helping prevent problems like depression, dementia, and Alzheimer's disease. It is necessary for the synthesis of dopamine and norepinephrine, which are neurotransmitters that help improve memory, concentration, and motivation.
2. Developing the fetal nervous system
Folic acid is fundamental, especially at the very beginning of pregnancy, to the formation of the fetal nervous system, preventing complications like cleft palate and spina bifida, a condition in which the spine and spinal cord do not form properly.
3. Preventing cardiovascular disease
Folic acid helps prevent cardiovascular disease, likely through reducing levels of homocysteine in the blood. Homocysteine is an amino acid that, when elevated, can cause damage to the blood vessels, increasing the risk for cardiovascular diseases like stroke, atherosclerosis, and heart attack.
4. Preventing anemia
Folic acid plays an important role in the formation of red blood cells, which are responsible for transporting oxygen throughout the body. Alterations in the formation of these cells can lead to a decreased number of red blood cells, resulting in anemia.
5. Maintaining healthy skin and hair
Folic acid is one of the vitamins responsible for the growth and maintenance of skin and hair cells. This includes promoting hair growth, keeping the skin hydrated, and helping to prevent premature aging.
6. Preventing certain types of cancer
Due to its role in gene expression and the formation of DNA and RNA, folic acid may help prevent certain types of cancer, such as intestinal cancer, lung cancer, breast cancer, and pancreatic cancer.
However, more studies involving human subjects are needed in order to prove a link between folic acid and cancer prevention.
Food sources
Foods that are high in folic acid include dark green vegetables like arugula and spinach; legumes like lentils and black-eyed peas; healthy fats like sesame seeds; and organ meats like beef and chicken liver.
Check out more folic acid foods.
Recommended intake
The recommended daily amounts of folic acid vary based on age and phase of life:
- 0 to 6 months: 65 mcg;
- 7 to 12 months: 80 mcg;
- 1 to 3 years: 150 mcg;
- 4 to 8 years: 200 mcg;
- 9 to 13 years: 300 mcg;
- 14 years and above: 400 mcg;
- Pregnant people: 600 mcg;
- Lactating people: 500 mcg.
Folic acid supplements are generally recommended in cases of folic acid deficiency and anemia and for people who are pregnant or breastfeeding. Supplements should be taken only as directed by your doctor or a registered dietitian.
Reference values
A blood test can be done to check levels of circulating folic acid in the body and identify a deficiency.
Reference values for folic acid are:
Reference values may vary according to the lab where the test is performed.
Results should be interpreted by the doctor or other healthcare professional who ordered the test, along with other blood tests such as a complete blood count (CBC).
Folic acid deficiency
Folic acid deficiency can be caused by low intake of folic acid-rich foods, conditions that affect the absorption of folic acid (such as regular consumption of alcoholic beverages, celiac disease, or inflammatory bowel disease), or increased demand for folic acid, such as during pregnancy.
Folic acid deficiency can cause symptoms like loss of appetite, nausea, vomiting, diarrhea, canker sores, and hair loss. Prolonged periods of folic acid deficiency can lead to megaloblastic anemia, causing symptoms like fatigue, muscle pain, and pallor.
Folic acid deficiency is also associated with complications of pregnancy, such as high blood pressure, miscarriage, and premature birth. Fetal complications include low birthweight and birth defects like spina bifida and cleft palate or cleft lip, in which there is an opening in the palate or above the upper lip that can extend up to the nose.
Can taking too much folic acid cause symptoms?
Ingesting more than 1000 mcg of folic acid per day can cause symptoms like:
- Loss of appetite;
- Nausea;
- Stomachache;
- Agitation;
- Abdominal distention.
Too much folic acid can also cause allergic reactions in people with a higher sensitivity to folic acid, causing symptoms like fever, itchy skin, and difficulty breathing.
Consuming too much folic acid from food sources alone is very rare.