Sunflower seeds, for example, are particularly high in magnesium, with 100 grams containing the recommended daily dose of 300 to 400 milligrams.

Cashew nuts, which contain around 270 milligrams per 100 grams, also contain a lot of magnesium. “The content is particularly high in grains, nuts, pulses, fruit, and vegetables like spinach, kale, and broccoli. Mineral water is also a source of magnesium,” says Rauh.

It’s important to note, however, that many vegetables, fruits, and seeds lose much of their magnesium content when cooked or peeled because the valuable mineral is often found in or near the skin. Whole grain “brown” rice, for example, contains around 160 milligrams of magnesium, whereas hulled or “white” rice contains almost none.

Getting magnesium through diet

What to do? The most important thing: Eat a healthy, varied, and balanced diet with sufficient fiber. This will generally provide the body with the required daily dose and prevent a magnesium deficiency.

Rauh recommends practicing a healthy lifestyle, too: “If you want to do something for your health, you should exercise, make time to eat regularly, and enrich your diet with nuts and fruit.” She advises against simply taking magnesium supplements to compensate for a “careless lifestyle.” In her opinion, long-term use of magnesium supplements should be discussed with your doctor.

Taking magnesium throughout the day

Anyone who takes magnesium supplements should not take more than 250 milligrams per day, and should ideally spread the intake out over two to three doses throughout the day. Magnesium supplements should also be taken in conjunction with regular exercise and a balanced diet.

But what about other popular magnesium products? Rauh is somewhat critical of those, especially magnesium oil: “There are no evidence-based studies that prove that magnesium can be absorbed through the skin,” she says.

Of course, some people swear by foot baths or sprays as a guard against magnesium deficiency. But does any of the magnesium actually end up in the body? It’s hard to say for sure: “The effectiveness of a product depends on many factors and it’s still unclear how well these products work,” Rauh emphasizes.

If you like magnesium oils, bath products, and sprays, go ahead and use them—it probably doesn’t hurt. Just remember, there isn’t much scientific proof of their benefits, so it’s best to follow the tried-and-true wellness basics of a healthy diet, adequate sleep, and sufficient exercise to cover all your bases.