Question 1

What is the best form of magnesium?

Accepted Answer

It depends on your goal. Magnesium glycinate is best for sleep, relaxation, and anxiety due to the calming effect of glycine and high bioavailability. Magnesium citrate is well-absorbed and good for general supplementation (also has a mild laxative effect). Magnesium oxide has the highest elemental magnesium per pill but the worst absorption (~4%) - best for treating constipation, not deficiency. Magnesium L-threonate (Magtein) may have unique benefits for brain health as it crosses the blood-brain barrier, but it's expensive and the human evidence is limited. Magnesium taurate is sometimes recommended for heart health.

Question 2

How much elemental magnesium is in magnesium glycinate?

Accepted Answer

Magnesium glycinate (magnesium bisglycinate) is approximately 14.1% elemental magnesium by weight. A capsule containing 1,000mg of magnesium glycinate provides about 141mg of elemental magnesium. A capsule listed as '500mg magnesium glycinate' provides about 70mg elemental magnesium. ALWAYS check the Supplement Facts panel for the elemental magnesium amount, which is what matters for dosing. Some brands helpfully list both the total compound weight and the elemental amount.

Question 3

Can I take magnesium glycinate every day long-term?

Accepted Answer

Yes. Magnesium is an essential mineral your body needs daily and does not store well. Long-term daily supplementation of 200-400mg elemental magnesium is considered safe for adults with normal kidney function. The NIH notes that chronically low magnesium intake is associated with increased risk of cardiovascular disease, type 2 diabetes, and osteoporosis. If anything, consistent daily supplementation is preferable to sporadic use.

Question 4

When is the best time to take magnesium glycinate?

Accepted Answer

For sleep: 30-60 minutes before bed. For general supplementation or blood pressure: any consistent time works, though many people prefer evening dosing. If taking a larger dose (300-400mg), splitting into morning and evening doses may improve absorption and reduce any GI effects. Taking with food is not required for glycinate, but can help if you experience any mild stomach discomfort.

Question 5

Magnesium glycinate vs magnesium citrate - which is better?

Accepted Answer

Magnesium glycinate is better for sleep, anxiety, and people with sensitive stomachs. It causes significantly less GI distress and the glycine has its own calming benefits. Magnesium citrate is better for general supplementation on a budget and for people who want mild constipation relief as a side benefit. Both have good bioavailability - substantially better than magnesium oxide. If your primary goal is sleep or relaxation, glycinate is the clear winner.

Question 6

Will magnesium glycinate help with anxiety?

Accepted Answer

The evidence is promising but not definitive. A 2017 systematic review in Nutrients found suggestive evidence that magnesium supplementation may reduce subjective anxiety, particularly in people who are magnesium-deficient. The glycine in magnesium glycinate may provide additional calming effects through its action as an inhibitory neurotransmitter. It is not a replacement for evidence-based anxiety treatments (therapy, medication), but may be a helpful adjunct, particularly if you are not meeting your magnesium needs through diet.

Question 7

How long does it take for magnesium glycinate to start working?

Accepted Answer

Onset depends on the benefit. Some people notice mild drowsiness within 30 to 60 minutes of the first evening dose because of the glycine component, which acts as an inhibitory neurotransmitter on its own. Consistent sleep-quality improvements typically show up after 1 to 2 weeks of nightly use. Blood pressure changes lag the most: the Zhang 2016 meta-analysis pooled trials in the 6 to 24 week range, so allow 4 to 8 weeks at 350 to 400mg elemental daily before judging effect on a reading. Muscle cramp and stress effects sit between those windows, usually 2 to 4 weeks. If you have noticed nothing after 8 consistent weeks at a clinical dose, the issue is more often the underlying cause than the supplement.

Question 8

Is magnesium glycinate safe to take during pregnancy?

Accepted Answer

Yes, at standard doses, but confirm with your OB before starting. The RDA for pregnant adults is 350 to 360mg elemental magnesium daily, slightly higher than the non-pregnant recommendation, and most prenatal vitamins do not include the full amount. Glycinate is generally the preferred supplemental form during pregnancy because it is well-tolerated and lacks the laxative effect common with citrate and oxide forms, which is useful given that constipation is already a frequent pregnancy complaint. A 2021 meta-analysis of randomized controlled trials (Liu et al., Taiwanese Journal of Obstetrics & Gynecology; PMID 34247796) found oral magnesium supplementation significantly reduced the frequency and intensity of leg cramps in pregnancy. Avoid the magnesium L-threonate (Magtein) form during pregnancy because it has not been studied in pregnant populations.

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Frequently Asked Questions

What is the best form of magnesium?

How much elemental magnesium is in magnesium glycinate?

Can I take magnesium glycinate every day long-term?

When is the best time to take magnesium glycinate?

Magnesium glycinate vs magnesium citrate - which is better?

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