B-vitamins are essential nutrients that help your body turn food into energy, create new blood cells, and keep your skin, brain and other cells healthy. While you can get plenty of B12 from meat, dairy and eggs, if you’re low, vitamin B supplements can help you stay on track.

Usually, B-vitamins are there to boost your energy but sometimes they can make you feel tired, especially when you’re just starting or taking high doses. Your body might need time to adjust or certain forms and amounts of B vitamins can have unexpected effects. Plus, if you have underlying health issues, that can play a part too.

For most people, taking B-vitamins daily is totally fine since they’re water-soluble and your body just flushes out what it doesn’t need. Just stick to the recommended doses on the label though, as too much can sometimes cause headaches, rashes or issues with gut health.