Benefits
Well-absorbed repletion
As a highly soluble salt, oral magnesium chloride dissociates readily and is efficiently absorbed, making it an effective choice for raising and maintaining normal magnesium status and supporting the many enzymes that require magnesium.
Metabolic health support
Magnesium participates in glucose metabolism and insulin signaling. In people with low magnesium, restoring adequate levels supports normal carbohydrate metabolism and helps maintain insulin sensitivity within the healthy range.
Muscle and nerve function
Magnesium is essential for normal muscle contraction, relaxation and nerve transmission. Adequate intake supports neuromuscular function and may help with the occasional muscle cramps associated with low magnesium.
Bone health contribution
About half of the body's magnesium resides in bone, where it supports the mineral matrix and normal bone structure. Adequate magnesium works alongside calcium and vitamin D to help maintain bone health.
Energy and fatigue
Because magnesium is needed to activate ATP, maintaining adequate magnesium supports normal energy-yielding metabolism and helps reduce tiredness and fatigue associated with insufficient intake.
Mechanism of action
High solubility and dissociation
Magnesium chloride dissolves completely in water and dissociates into magnesium and chloride ions, presenting free magnesium for paracellular and TRPM6/7-mediated transcellular absorption in the intestine.
Enzyme cofactor activity
Absorbed magnesium serves as a cofactor for over 300 enzymatic reactions, including those forming and using ATP, synthesizing nucleic acids and proteins, and regulating ion pumps that maintain cellular electrochemical gradients.
Insulin and glucose handling
Magnesium supports tyrosine kinase activity of the insulin receptor and downstream glucose uptake. Correcting low magnesium can improve cellular insulin signaling and help maintain normal glucose handling.
Questionable transdermal route
Topical magnesium chloride is promoted for skin absorption, but charged magnesium ions poorly penetrate the lipid-rich stratum corneum, so systemic delivery from sprays and baths remains scientifically unsupported.
Clinical trials
Randomized, double-blind, placebo-controlled trial over 16 weeks
Adults with type 2 diabetes and low serum magnesium
Daily oral magnesium chloride solution improved insulin sensitivity and metabolic markers, with lower insulin resistance and reduced fasting glucose compared with placebo. Benefits were seen in people who started with low magnesium, underscoring repletion rather than a universal effect.
Narrative review of skin-absorption studies
Human and laboratory skin-penetration research
The review concluded that claims for transdermal magnesium are scientifically unsupported, as ionized magnesium does not readily cross intact skin and available studies are small and methodologically limited. Oral magnesium remains the documented route for raising magnesium status.