Someone told me I should take 5 mg. of folic acid during pregnancy. This is five times the amount that my doctor has prescribed. Is this dangerous?
Follow your doctor's prescription. Just because they're called vitamins doesn't mean that there's no toxicity in excessive amounts. Vitamin A, for instance, can actually cause birth defects in excessive amounts. For folic acid, 0.6 mg., or 6/10 of what you're taking, is what is recommended to prevent birth defects, so what you're on is already plenty. I would not recommend quintupling it.