The app is full of “sleep hacks,” with magnesium mocktails (also known as the “sleepy girl cocktail”) and lettuce water being among the most viral. Research shows that magnesium threonate crosses the blood-brain barrier better than the others, making it a more effective sleep aid, explains Dimitriu. Pay attention to elemental magnesium—the actual part of a magnesium supplement your body can use. In common supplements, like magnesium citrate, glycinate, or threonate, magnesium is bound to other substances, and the amount of elemental magnesium will always be less than the total amount of the magnesium salt. For example, 2,000 mg of magnesium threonate usually provides only about 140 mg of elemental magnesium, safely below the limit, explains Dimitriu.