It depends on individual gene variants and other factors. I have never seen a fact or statistic about what you are asking for.

BTW I read one of your other posts so you may be interested in this:

https://www.amazon.com/Non-Methylated-Multi-Vitamin-90-capsules-Veagan/dp/B01BJ7FV1K

You add your choice for folate and B12 in separate pills.