People who eat magnesium-rich foods like spinach and almonds may have bigger, healthier brains

• A new study suggests magnesium-rich diets can help brains stay healthier for longer.
• Foods high in magnesium include leafy green vegetables and nuts.

"Brain care supplements" are having a moment, but a diet rich in leafy greens and nuts might be the best way to protect the body's most complex organ.

A recent study found that people who ate diets high in magnesium had less age-related brain shrinkage. They also had smaller white matter lesions, a sign of brain aging. The effects were especially pronounced in women, particularly post-menopausal women.

The study, published on March 10 in the European Journal of Nutrition, analyzed the health data of about 6,000 UK-based participants, aged 40 to 73. Researchers from the Australian National University measured dietary magnesium, found in leafy green vegetables like spinach, legumes, nuts, seeds, and whole grains, by administering five questionnaires over 16 months.

The National Institutes of Health recommends adults eat about 320 mg to 430 mg of magnesium per day, but study participants who had the healthiest brains ate above 550 mg.

Increasing magnesium intake "may lead to significantly better brain health, which would also be expected to contribute to greater preservation of cognitive ability, and lower risk or delayed onset of dementia in later life," researchers stated.

Brain care and magnesium supplements are the latest wellness fads

Wellness gurus and startups, including the Bella Hadid-backed "functional beverage" line Kin Euphorics, have invested in "brain care" products with magnesium which claim to improve concentration and anxiety. But scientists have done little to no testing to verify these claims — and the studies that do exist are inconclusive.

Magnesium supplements are also having a moment on TikTok. Videos claiming magnesium supplements cured users' anxiety and insomnia have garnered tens of millions of views.

But this new study shows that spending money on expensive supplements isn't necessary to boost brain function — just eating more spinach can be enough to get the physical and mental health benefits of magnesium.

Magnesium can also lead to better rest

In addition to the new evidence of promoting healthy brain aging, magnesium also has other health benefits. Magnesium promotes muscle relaxation by blocking the calcium in your body from contracting muscles, sleep scientists previously told Insider, leading to better rest.

Magnesium also promotes sleep by counteracting glutamate, an amino acid and neurotransmitter that spikes in the body when you're awake and when you're in pain, psychologist and registered dietitian Dr. Supatra Tovar previously told Insider. Uninterrupted, regular sleep has been linked to better memory and focus, which might account for magnesium's perceived mental health benefits.

Tovar also said people interested in magnesium are better off eating more nuts than reaching for the supplement bottle. Tovar said the body processes nutrients in food better than those manufactured and put into supplements.

Supplements can also cause diarrhea and other gastrointestinal problem, and very large amounts of magnesium could lead to low blood pressure, lethargy, depression, and confusion.