Vitamin B-9 (folic acid) is part of the B-complex group of vitamins that can dissolve in water. These B-complex vitamins help our bodies break down complex carbohydrates into simple sugars used for energy, and for new tissue and cell growth. Folic acid (folate) also works closely with vitamin B-12 to help produce red blood cells, and is an essential vitamin critical to normal brain function, especially when tissue and cells are rapidly growing, such as during pregnancy, infancy, and adolescence. However, can a high folic acid level be detrimental to your health?
Too Much of a Good Thing?
A high folic acid level is commonplace with those who consume a diet rich in folate, such as dark green vegetables, lentils, and citrus fruit. Taking more than your body needs from food is not necessarily a health risk because excess B vitamins are normally excreted from the body through urine. However, some people are at risk for folate toxicity from dietary supplements, and fortified foods. Another risk involves the use of folic acid to treat a folate deficiency, but because a folate deficiency closely resembles a vitamin B-12 deficiency, if the B- 12 deficiency goes undiagnosed, the treatment can lead to irreversible brain damage.
How Much Can You Take?
Medical experts agree that the normal range of folic acid in the blood is between 2.7 and 17.0 nanogram/milliliter. So how much folate acid can you take?
- Children 1 to 3 years old: 300 micrograms (mcg) daily
- Children 4 to 8 years old: 400 mcg daily
- Children 9 to 13 years old: 600 mcg daily
- Adolescents 14 to 18 years old: 800 mcg daily
- Adults 19 and older: 1000 mcg daily
Important Note: Women who plan to become pregnant can benefit from higher doses of folic acid to prevent brain and spine defects in the developing fetus. They should plan to increase their intake from 500 to 800 mcg daily, at least a month before they decide to conceive, and those that wish to breastfeed should aim for at least 500 mcg daily.
Possible Causes of High Folic Acid Level
1. Pernicious Anemia
Pernicious anemia occurs when the your body doesn't make enough healthy red blood cells resulting from a vitamin B-12 deficiency, and a high folic acid level might hide the damaging effects of the deficiency by correcting the anemia caused by a vitamin B-12 deficiency, but doesn't correct the neurological damage that may also occur. Pernicious anemia increases serum folate levels by allowing the accumulation of the most common form of folate — methyltetrahydrofolate in your blood. Pernicious anemia can cause health issues such as headache, memory loss, nerve damage, and digestive tract problems, along with a higher risk for stomach cancer and weakened bone strength.
2. Blind Loop Syndrome
Blind loop syndrome occurs when a segment (blind loop) of your small intestine is bypassed during digestion, meaning the food you consume doesn't move through your digestive tract normally. The slow moving food and waste will begin to ferment, creating conditions for bacterial overgrowth, and results in a malabsorption of essential nutrients. This often causes a high folic acid level, malnutrition, sudden weight loss, and diarrhea. However, the hallmark feature of blind loop syndrome is megaloblastic anemia, which results from inhibition of DNA synthesis during red blood cell production, and is caused by the disruption of vitamin B12 absorption.
3. Increased Food Intake
Increased food containing folic acid may elevate your serum folate levels, but any high folic acid level associated with the food is likely to be short lived, and temporary. Folate consumption and temporary elevated serum folate levels generally do not cause any health risk, and the risk of toxicity from supplemented folic acid consumption is very low. However, some medical experts suggest a high level of folic acid may induce seizures if you are taking anticonvulsant medication. Consult with your healthcare professional before consuming a folate supplement when you are taking anticonvulsant medication.
How do You Know If You Have High Folic Acid Level?
Know the Signs
Although people taking folic acid typically don't notice any side effects, some people may experience the following symptoms while having too much folic acid in the body.
Mild side effects include:
- Digestive issues
- Nausea
- Decreased appetite
- Gas, and bloating
- A foul taste in the mouth
- Disturbed sleep
- Depression
- Overexcitement
- Feeling irritable
- A zinc deficiency
More serious side effects include:
- Psychological behavior
- Numbness and/or tingling
- Mouth soreness
- Weakness, and fatigue
- Trouble concentrating, and confusion
- Seizures
- An allergic reaction
- Swelling of the face and throat
- Skin rash
If you are experiencing any of these symptoms, it's important that you consult with your healthcare professional. Your doctor may order folate levels tested to check for any folate or vitamin B-12 deficiencies that may be causing your symptoms.
Take a Folic Acid Test
How to Prepare
Before the test, consult with your healthcare professional any medications or supplements you are taking, because these can interfere with the results. Your doctor will discuss with you about how to take these before the test. You should fast prior to testing, because serum folate levels increase with eating. Avoid food and liquids, other than water, for six to eight hours before the folic acid test. It's generally better to fast all night, while arranging for an early appointment the next morning.
What Will Happen During a Folic Acid Test?
A folic acid test involves drawing a small sample of blood, usually from a vein on the inside of your elbow. A healthcare professional who performs the test will do the following:
- Swab the area with an antiseptic.
- Wrap an elastic band around the top of your arm, causing the veins below the band to swell.
- Once a vein is found, they will insert the needle and draw some blood.
- When they're finished, the needle will be removed and a cotton ball will be applied to stop any bleeding.
- A bandage is used to cover the puncture site, and the blood sample is sent to a laboratory for analysis.
- Review the results with you in a follow up appointment.
What do the Results of a Folic Acid Test Mean?
- A high folic acid level is usually not a problem; however, it could indicate a vitamin B-12 deficiency. This is because the body needs vitamin B-12 to process folic acid properly. Your healthcare professional may want additional testing to make sure a high folic acid level isn't resulting from a vitamin B-12 deficiency.
- A low folic acid level may indicate an anemia, folic acid deficiency, or malabsorption problems. Your physician can explain what your specific results mean, and what the next steps should be.