Thorne, Magnesium Glycinate, Capsules (120 mg per Capsule) Review

Evidence that magnesium alone eases stress or anxiety is suggestive but weak and mixed. At two capsules a day this product gives 240 mg, close to the 248 mg used in one trial. In that trial, 126 adults with mild to moderate depression took 248 mg daily for 6 weeks, and their anxiety scores improved more than in people given nothing, but there was no placebo ^[1]. In 264 stressed adults with low magnesium, 300 mg daily for 8 weeks cut stress scores by about 42%, again without a placebo group ^[2]. A 24-week placebo-controlled trial in 49 adults found that 350 mg daily lowered the stress hormone cortisol ^[3]. A pooled analysis of 52 trials found a small benefit for magnesium on depression scores ^[4]. However, placebo-controlled trials found no clear sleep benefit in 100 older adults ^[5] and no change in anxiety in 44 women with osteoporosis ^[6]. Animal and cell studies are never counted.

Magnesium is the main ingredient, and most of the panel recommends or uses it: five recommend it, four use it, and one is neutral. Sleep is the top reason, and the forms named most often are threonate and glycinate. Four panelists take 400 mg of threonate before bed, while others suggest 300 to 400 mg a day from diet and supplements, 400 to 500 mg a day for most people, or up to a gram for bone health. Other reasons given include vitamin D function, muscle cramps, blood pressure, bone health, and hydration through electrolyte drinks, and one panelist notes that magnesium does not fix waking up during the night. One panelist says glycinate absorbs better than oxide, and another advises threonate only for people who are low in magnesium; no one said they stopped taking it.

The rules graded this as shown not to work, but the studies are mixed: 19 of 36 improved, a placebo-controlled trial lowered cortisol, and the two placebo trials with no benefit looked at sleep and at anxiety in women with osteoporosis, so the evidence is weak and conflicting rather than negative. So it is graded Tier 4, as the studies disagree.

Combine with: Magnesium is often paired with L-theanine, since both act on calming pathways in the brain tied to relaxation. It is often paired with vitamin B6, which is used in how cells take up and hold magnesium. Ashwagandha is often paired with it because both are used for stress support. Magnesium is also often paired with taurine, which acts on the same calming signals in the nervous system.