I get this question all the time in my practice. You should take a multivitamin or pre-natal vitamin with food in the morning or noontime. Why? Certain vitamins such as vitamins A, D, E and K require fat in your stomach to become absorbed. If you take them with an empty stomach and do not eat anything with fat afterwards, you will absorb very little or none of these vitamins.
Why during the daytime and not with dinner? Vitamin D requires the sun to become activated in the body, otherwise it is not as beneficial. You’re more likely to be exposed to the sun outdoors at some point if you take the multivitamin in the morning.
As a side note, I recommend avoiding the popular “gummy” vitamins or anything that says it can be both a candy and a vitamin. Many of these are filled with sugar, starch, gelatin, and preservatives. Moreover, several vitamins can degrade easily when they are incorporated into with these fillers. You will be getting less of the vitamin being absorbed than you pay for. Also, if you have kids, they can easily confuse the gummy vitamins with candy and can easily overdose on them. Vitamin overdoses can be life threatening, particularly related to vitamin A and iron. With children, the danger is magnified since their bodies are smaller and they cannot excrete extra vitamins as quickly as an adult.