Does magnesium permeate the skin? An ex vivo investigation of magnesium ion delivery through intact and barrier-disrupted skin.
Level 5 - mechanism / opinion, no new human data
Ex vivo animal tissue bench study (no human subjects).
PubMed 42372834 · doi:10.1016/j.ejpb.2026.115173
What was done
Researchers measured magnesium ion permeation from a saturated aqueous magnesium sulfate monohydrate solution across intact and tape-stripped (barrier-disrupted) porcine skin using an ex vivo Franz diffusion cell model. Magnesium permeation was quantified after 24 hours via inductively coupled plasma mass spectrometry (ICP-MS) and compared against untreated controls.
What was found
Across intact skin, there was no significant difference between treated and control samples, with 24-hour magnesium permeation measuring 8.3 ± 3.4 µg cm⁻² for the magnesium-treated group versus 3.9 ± 0.8 µg cm⁻² for controls. In contrast, tape stripping increased permeation by several orders of magnitude to approximately 13.0 ± 5.3 mg cm⁻², alongside substantial inter-sample variability.
Why it matters
These findings challenge the premise of transdermal magnesium supplementation on healthy skin, indicating that the intact stratum corneum essentially blocks passive aqueous magnesium delivery.
Limits
The study was conducted ex vivo on porcine skin rather than in vivo in humans, lacking systemic blood clearance. It evaluated only a simple saturated aqueous magnesium sulfate solution without complex cosmetic or penetration-enhancing vehicles, and the abstract does not report the exact number of skin replicates tested.
Cited by
- supports There is no scientific evidence demonstrating that soaking in Epsom salt increases plasma magnesium levels or improves muscle cramps.