In the 1600s, people in England visited a well on Epsom Common seeking relief from rich diets. They drank water with a strong laxative effect, later discovered to contain high levels of magnesium sulphate. Today, some claim that taking magnesium supplements can improve sleep, energy, and concentration.
However, columnist Alice Klein found that the evidence for these benefits is scarce. She questions whether magnesium really meets its ‘super mineral’ hype.
Source: https://www.newscientist.com/article/2517316-can-magnesium-supplements-improve-sleep-energy-and-concentration