“Supplements that contain a little bit of everything actually contain a lot of nothing,” Medlin says. This isn’t necessarily the case for vitamins, she caveats, as often when it comes to vitamin supplements we only need very small amounts.

But for things like herbal preparations, essential oils and amino acids, we actually need really large amounts to elicit any of the beneficial effects we see in studies, according to Medlin. “Often companies cram in tiny amounts of buzzy ingredients because people are looking for them rather than having any interest in the required dose to have benefits,” she adds.

How to make sure your supplements are safe and effective, according to an expert