Many observations related to magnesium’s effect on reducing disease risk are likely due to correction of a deficiency. In other words, it may not be the case that supplemental magnesium is beneficial per se; instead, magnesium deficiency may lead to several health problems, many of which may be related to chronic low-grade inflammation.[1] There is also the possibility of reverse causation because many modern diseases (i.e., obesity and diabetes) may lead to a magnesium deficiency.
Nonetheless, there are well-documented mechanisms that explain why magnesium may benefit health.
For one, magnesium plays a role in beta-cell activity in the pancreas, influencing insulin secretion and, therefore, our ability to regulate blood glucose. Magnesium deficiency can lead to impaired insulin secretion, impaired glucose utilization, and insulin resistance — all of which contribute to the development of type 2 diabetes.[2]
In the cardiovascular system, magnesium regulates calcium concentrations, which enhances vascular relaxation and inhibits vasoconstriction, leading to healthy vascular tone and protecting against high blood pressure (hypertension). Magnesium also improves endothelial function by directly stimulating the release of nitric oxide(NO).[3]
In the brain, magnesium binds to and blocks the actions of NMDA receptors, thereby preventing glutamate-dependent transmission of cortical spreading depression — one mechanism involved in the pathogenesis of migraine headache. Magnesium is also a GABA agonist. Magnesium affects the function of serotonin receptors, influences platelet aggregation, and regulates the synthesis and release of several neurotransmitters. These mechanisms explain magnesium’s benefit for migraine, as well as the potential for magnesium to improve sleep and other aspects of neurological health.[4][5]