Experts say vitamin and supplement timing affects absorption

ANBAR, Iraq — Research indicates that the effectiveness of vitamin and dietary supplements depends partly on when they are taken. Fat-soluble vitamins A, D, E and K are absorbed more efficiently when taken with meals, while water-soluble vitamin C and the B-complex vitamins can be absorbed on an empty stomach, according to the findings. Mineral supplements require similar attention. Calcium can interfere with iron absorption, so the two are recommended at different times. Iron is generally absorbed better on an empty stomach, though it can cause stomach discomfort in some people, in which case it may be taken with food. B-complex vitamins can have a stimulating effect and are not recommended in the evening, while magnesium, which has a relaxing effect, can be taken at night, the researchers said. Experts noted that reliable evidence on these timing effects remains limited and that for most people, consistent daily use matters more than the specific time of intake. Supplements do not replace a balanced diet, and healthy individuals following a varied diet typically do not need them. Those taking other medications are advised to consult a doctor before starting any supplement.