Magnesium Oxide
A cheap form with a high percentage of elemental magnesium but poor absorption, so most of it stays in the gut. That makes it effective as an occasional laxative or antacid, but a weak choice for genuinely raising magnesium levels.
Best for
Occasional constipation and lowest cost
Absorption
Low
Tolerability
Strongly laxative
Typical timing
Evening for sleep support; with food to reduce GI upset
How to take Magnesium Oxide
A typical dose of Magnesium: 200–400 mg elemental magnesium per day. Best timing: Evening for sleep support; with food to reduce GI upset. The form you choose mainly affects absorption and how easily it sits with your stomach, not the overall dose.
Where to buy Magnesium Oxide
Choose a third-party-tested brand; the label should name this form explicitly.
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