The timing of taking a multivitamin can depend on the specific nutrients in the supplement and your individual needs. In general, it is best to take a multivitamin with a meal, as this can help your body absorb the nutrients more effectively. If the multivitamin contains iron, it is recommended to take it in the morning with breakfast. Iron can cause stomach upset if taken on an empty stomach and interfere with sleep. Vitamins B12 and B9, or folic acid, which are essential for energy and metabolism, are best taken in the morning as they can give you a boost of energy during the day. On the other hand, if the multivitamin contains melatonin, a hormone that helps regulate sleep, it is best to take it at night before bedtime. It is best to check the label of the multivitamin and check with your healthcare provider for their recommendation.