Findings from clinical trials revealed benefits for magnesium L-threonate, a form of magnesium with good brain bioavailability, in people with poor sleep and cancer patients treated for pain.^1,2

A three-week randomized, double-blind trial found that sleep quality and daytime functioning significantly improved among individuals who received magnesium L-threonate compared with a placebo. Magnesium L-threonate was significantly associated with better deep sleep and rapid eye movement (REM) sleep scores, light sleep time, and activity and readiness tracked by wearable devices. Participants who received magnesium L-threonate reported improvements in behavior after awakening, grouchiness, mood and mental alertness compared with the placebo group. Daily diary entries documented better-perceived energy and daytime productivity. “The results are consistent with the action of magnesium on the brain reported elsewhere and suggest a broader positive impact of magnesium L-threonate beyond simply sleep,” Heather A. Hausenblas and colleagues concluded.

Another randomized, double-blind trial revealed that magnesium L-threonate was better at enhancing the pain-relieving effects of opioid drugs used by cancer patients compared with a placebo. Opioids are used to treat cancer-associated pain; however, tolerance to the drugs weakens their pain-relieving benefit. Trial participants who received magnesium L-threonate were able to reduce the dosage of drugs needed to control pain. Constipation, a common side effect of opioid drug use, significantly decreased after a week among those who were given magnesium L-threonate and remained significantly improved compared with the placebo group until the end of the study. “As far as we know, this is the first randomized controlled clinical trial to study the effects of an oral magnesium compound on opioid analgesia in patients with cancer pain,” authors Siyin Wu and associates announced.

The first trial, which included 76 men and women who reported poor sleep quality, was reported in the December 2024 issue of Sleep Medicine: X. Thirty-eight participants received 1,000 milligrams magnesium L-threonate per day and an equal number received a placebo for three weeks. Sleep quality and daytime mood and activity were assessed weekly using questionnaires, and daily via diaries and wearable sleep and activity trackers.

The second trial, reported in the journal Cancer Medicine, included patients with advanced cancer who were treated with morphine for pain. Forty-two participants received 1.5 grams or 2 grams (according to body weight) of magnesium L-threonate and 42 received a placebo daily for 12 weeks. Participants were permitted to adjust their opioid drug doses according to pain levels.