What is the most common cause of hypomagnesemia?

Hypomagnesemia, or low magnesium levels in the blood, can arise from various causes, but one of the most common is chronic alcoholism. Alcoholism leads to a number of physiological changes that negatively impact magnesium levels. First, alcohol can interfere with magnesium absorption in the gastrointestinal tract, reducing the amount of magnesium that enters the bloodstream. Second, alcohol can increase urinary excretion of magnesium, exacerbating the deficiency.

Additionally, individuals with alcoholism often have poor nutritional intake and may have dietary deficiencies in magnesium and other essential nutrients. This combination of decreased intake, altered absorption, and increased loss through urine contributes significantly to the development of hypomagnesemia in those who consume alcohol excessively.

In contrast, while diuretics can induce magnesium loss and renal disease can lead to disturbances in electrolyte balance, these factors are not as prevalent or defining for hypomagnesemia as the chronic impact of alcoholism. Malnutrition can also lead to hypomagnesemia, but it is generally less common compared to the effects of chronic alcohol consumption, which creates a multifaceted environment for magnesium depletion.