I am six months pregnant. I was advised in the first trimester to take folic acid supplements because it's almost impossible to get enough naturally. I recently read that overconsumption may lead to a greater risk of bowel cancer. Can I harm my foetus by taking too much?
Folic acid has come into the limelight only since it was shown that women who take it while wishing to conceive and for the first 12 weeks of pregnancy are much less likely than others to have a baby with neural tube defects (such as spina bifida). By your sixth month, extra folic acid makes no difference - the baby's spine has already formed - so you can stop the supplement. Folic acid is exceptionally benign, and the extra amounts proposed in bread are well within a normal range found in other foods. There is no evidence that the 5mg daily dose has harmed babies when taken from before conception and up to 12 weeks. Some patients with bowel problems may need 15mg a day - 40 times the normal daily intake. I find no indication that this has harmed them.
Why do I keep getting athlete's foot? Why don't I become immune to it, as with other infections?
The fungal infection is in the dead layer of the epidermis, or 'outer' skin, where there are no blood vessels to carry the immune system's defences to it. So we don't build up long-term antibodies to it, and if we did they couldn't reach the skin surface to destroy it, anyway. Maybe our bodies haven't yet found a way of destroying it. Evolution hasn't made us perfect.
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