They said that B vitamins are best taken together so for this post, I'll talk about B vitamins as a group, known as B Complex.

B complex vitamins are water-soluble, so the body can only absorb so much at a given time (unlike fat-soluble vitamins, which are stored until they’re needed). B vitamins boost energy, so it is best to take them in the morning instead of evening as they can affect sleep.

B's are best absorbed on an empty stomach, however, sensitive stomachs (and maybe even gastric bypass patients) should take them with a little food — just before eating breakfast and lunch. Splitting the dose can ensure steady blood levels. 

It is suggested to look for a formula that contains well under 100 milligrams of B6, however, it is always recommended to consult your surgeon or physician before taking or adding supplements and vitamins.