Certain vitamins and supplements should generally be avoided at night because they can interfere with your sleep cycle or provide a stimulating effect that keeps you awake. Vitamin B12 and the broader B-complex are notorious for their role in energy metabolism; taking them late in the evening can cause a "wired" feeling or vivid dreams. Vitamin D is also best taken in the morning or midday, as it is naturally produced by the body in response to sunlight and is linked to the suppression of melatonin, the hormone that helps you fall asleep. Similarly, Multivitamins often contain a mix of these energizing components and are better processed when taken with your first meal of the day. On the other hand, minerals like Magnesium are excellent for nighttime use as they promote muscle relaxation and a sense of calm. If you find yourself tossing and turning, check your supplement regimen; moving your "energy-producing" vitamins to breakfast can significantly improve your sleep hygiene while ensuring you get the full nutritional benefit of the supplements.