Before we start discussing folate toxicity, it will be good to understand what is folate and folic acid. Both the terms are used to describe a water-soluble vitamin B. Folate is a naturally found nutrient in foods, while folic acid is the synthetic form of folate and is mostly found in fortified foods and in form of supplements too. Deficiency of folate can cause serious health problems, and folate is very important for pregnant women and lactating women. But, too much of folate is also not good as it can lead to toxicity.
Understanding the recommended dosage of folate will help you understand its toxicity better. The Institute of Medicine at the National Academy of Sciences in 1998 has set the following Recommended Dietary Allowances for folic acid.
- For pregnant women - 600 mcg/day
- For lactating women - 500 mcg/day
- For infants between 0 to 6 months - 65 mcg/day
- For infants between 6 -12 months - 80 mcg/day
- For children between 1 - 3 years - 150 mcg/day
- For children between 4 - 8 years - 200 mcg/day
- For males between 9 - 13 years - 300 mcg/day
- For males 14 years and older - 400 mcg/day
- For females between 9 - 13 years - 300 mcg/day
- For females 14 years and older - 400 mcg/day
Given above were the recommended dosage of folic acid. The Institute of Medicine at the National Academy of Sciences in 1998 set a tolerable upper limit of 1,000 mcg. Toxicity from folate generally doesn't occur as it is water soluble and get excreted by the body. Also, there are no health benefits from excessive intake of folate. But, the toxicity of folate occurs when there is a very high intake of it. If folate is taken in high amount like 1,000 or 2,000 mcg, then it gives a person the same symptoms which are seen by the deficiency of it. A person can show symptoms like intestinal dysfunction, insomnia, irritability and malaise. Other folate toxicity symptoms include skin reaction and even seizures.
If there are further high doses of folic acid, then it tends to interfere with the effectiveness of methotrexate, which is anticancer medication used during chemotherapy. It can also inhibit absorption of estrogen, anticonvulsant drugs, barbiturates, zinc and sulfasalazine. People who are at the risk of any heart diseases, can further risk their condition by folate toxicity. Overdose of folic acid can also cloak deficiency of vitamin B12. Folic acid supplement will help in treating condition like anemia which is caused by vitamin B12 deficiency, but the nerve damage which is related with this deficiency can't be detected. This can cause harm to the body, as it will inhibit diagnosing deficiency of other nutrients.
Prevention of folate toxicity is simple. Avoid excessive intake of folate. Understand the daily intake of folate and sticking to it is the solution. Refrain from overdose of folic acid supplements or enriched foods. Consult your doctor before you go on any folate supplements. Also, instead of depending on supplements, go for natural foods high in folate like asparagus, avocados, broccoli, beans, beets, brussels sprouts, bananas, peanuts, soy, oranges, lamb, turkey, beef, crab, eggs, fish, etc.
This was about what is folate poisoning, and what to do when one has poisoning. So, follow recommended dose of folate and keep in mind the preventive tips to avoid any folate toxicity. If one has poisoning, then treatment depends upon the symptoms shown by the patient. For example, if the person is suffering from insomnia, then some medication which helps to sleep better will be given.