What is Vitamin B9?

Vitamin B9 is one of the eight-member B-vitamin family. In its natural state in foods, it is known as folate; when manufactured and used in food supplements, such as multivitamins, it is called folic acid. Intake of the right amount of vitamin B9 helps the brain function properly and protects against anemia — an unhealthy low count of red blood cells. Pregnant women are typically urged to take higher-than-normal amounts of vitamin B9 to guard against anemia, birth defects, and miscarriages. The Recommended Dietary Allowance (RDA) of vitamin B9 is 400 micrograms (mcg) — most adults ingest the right amount of folate in a normal diet.

Folate/folic acid deficiency can have serious consequences, affecting the brain, the digestive system, and overall general health. Too little vitamin B9 can result in forgetfulness, irritability, depression, or mental sluggishness. Deficiency of this important vitamin can also result in gastrointestinal problems, appetite loss, gingivitis, shortness of breath, and poor growth rate in infants and children. Insufficient folate/folic acid in pregnant women can cause birth defects, such as cleft palate, brain damage, or even result in loss of the pregnancy. Also, there is growing evidence that low levels of this vitamin may contribute to Alzheimer's disease.

Generally, a folate/folic acid deficiency can be traced to several causes. It is commonly found in expectant mothers because they need more vitamin B9 than normal to share with the unborn child. Other causes include irritable bowel syndrome, celiac disease, and alcoholism. Some medications also lower levels of the vitamin. Typically, a person should always read the label instructions for medicines to see the manufacturer's recommendations.

Vitamin B9 occurs naturally in certain foods and is also sold in synthetic form. Good natural sources of folate include leafy vegetables, such as lettuce, spinach, and broccoli; fruits, such as melons, lemons, and bananas; fruit and vegetable juices; meat from animal organs, such as beef liver and kidneys; bakery products containing whole grains and wheat germ; and kidney, white, and lima beans. In the United States (US), all grain and cereal products are fortified with folic acid with the approval of the US Food and Drug Administration (FDA). Synthetic vitamin B9 is best taken as an ingredient in multivitamins or in combination with other members of the B-vitamin family because the companion ingredients are necessary to activate it. A person should always check with a health care professional before taking folic acid or giving it to someone else.