Yes, it is generally safe to take vitamin D at night. Many people can take it in the evening without any problems, especially if it is taken with a meal containing healthy fats, which helps its absorption. Some studies even suggest that taking vitamin D at night may improve sleep quality and duration because vitamin D plays a role in regulating melatonin, the hormone that triggers sleepiness. However, some individuals might experience sleep disturbances if they take vitamin D too close to bedtime, possibly due to its influence on melatonin production. For those who find their sleep affected, taking vitamin D in the morning might be a better option. In summary, vitamin D can be taken at night, preferably with food, but if it disrupts sleep, consider taking it earlier in the day. Monitoring how your body responds is important to determine the best timing for supplementation.