Common doses in adult supplements range from 400 to 800 micrograms, and common doses in children's multivitamins range from 200 to 400 micrograms. Folic acid can be taken with food, but it can be absorbed better on an empty stomach.
According to the office of dietary supplements, only about 85% of folic acid in the blood will enter the blood if taken with food. When taken on an empty stomach, almost 100% folic acid will become bioavailable.

It is generally recommended that you take complex B supplements instead of individual B vitamins. Doing so can lead to imbalances and / or mask lack of symptoms. For example, folic acid supplements can sometimes mask the potential risk of B12 deficiency.
But we recommend:
Magnafolate® L-Methylfolate—maximizes the supplementation delivering a "finished" folate the body can immediately use without any kind of metabolization.
It can better supplement the folate that the body lacks.
Jinkang Pharma ,the Manufacturer & Supplier of L-Methylfolate.