Despite some bold claims, multivitamins might not be as good for your health as some companies make out. They’re often believed to help reduce your risk of chronic diseases, like heart disease. But, extensive reviews don’t show this. So in healthy people, it’s unlikely they have any benefit.
Also, if you do take a multivitamin and are on medication, make sure these won’t interact with each other. This is why it’s a good idea to speak to a doctor or pharmacist before starting any supplement.
In most cases, multivitamins won’t be harmful. But sometimes, taking large doses of certain nutrients can have serious side effects.
Water-soluble vitamins
If you have too much of a water-soluble vitamin, like vitamin C or B vitamins, your body will flush the excess out, so it will rarely be harmful. But mega-doses can potentially cause issues. For example, too much vitamin C supplement can cause diarrhoea and too much vitamin B7 can cause liver damage.
Fat-soluble vitamins
In the case of fat-soluble vitamins, these can build up in your body — potentially causing harmful side effects. For example, too much vitamin A over many years might affect your bones and increase your risk of fractures as you age. Or taking too much while pregnant can harm your unborn baby.
Minerals, like iron, can also be harmful if you have too much.
As a result, it’s better to understand if you’re deficient in a particular nutrient and to take a supplement only with that nutrient.
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