How to choose
Start with your goal. For sleep, stress, or PMS, many women prefer magnesium glycinate — it's well absorbed and gentle on the stomach. For constipation, citrate draws water into the bowel (a pro or con depending on your needs). Oxide is the cheapest but the least absorbed, so a big number on the label can be misleading. L-threonate is promoted for cognition, but the human evidence is still limited.
Whatever the form, check the elemental magnesium per serving, confirm third-party testing, and avoid proprietary blends. If you have kidney disease or take medications, ask a clinician first — magnesium can interact with some drugs and isn't right for everyone. Use our Supplement Trust Scorecard to vet any product, and see lab-result interpreters if you've had bloodwork.
Frequently asked questions
What is the best form of magnesium for women?
It depends on your goal. Magnesium glycinate is a popular all-rounder for sleep, stress, and PMS because it's well absorbed and gentle. Citrate is good if you also want help with constipation. Oxide is cheap but poorly absorbed. L-threonate is marketed for the brain, with limited evidence so far.
How much magnesium should a woman take?
The recommended total intake for most adult women is roughly 310–320 mg per day from food and supplements combined. Supplements should list the elemental magnesium per serving. Very high doses can cause diarrhea, and magnesium isn't suitable for everyone — check with a clinician, especially if you have kidney problems.
Is it better to take magnesium at night?
Many people take magnesium in the evening because it can feel calming and may support sleep, but there's no strict rule. Consistency matters more than timing. Take it with food if it upsets your stomach.