Magnesium

Magnesium is one of the hardest working minerals in your body, involved in over 300 enzymatic reactions. It supports muscle and nerve function, energy production, bone health, heart rhythm, and blood sugar regulation. Despite its importance, magnesium deficiency is surprisingly common and often overlooked. Your body stores most of its magnesium inside cells and in bone, only about 1% circulates in the blood. This means a blood test can sometimes appear normal even when your total body stores are running low. Still, serum magnesium remains the standard screening test and is useful for detecting significant depletion.

Low magnesium is common in people who eat a highly processed diet, drink alcohol regularly, take certain medications (such as proton pump inhibitors or diuretics), or experience chronic stress. Symptoms of deficiency can be subtle at first, muscle cramps, poor sleep, irritability, and fatigue, but prolonged depletion can affect heart rhythm and bone density.

Magnesium works in close partnership with calcium and vitamin D. When magnesium is low, your body may struggle to regulate calcium properly, and vitamin D activation can be impaired. Athletes and those who exercise intensely may have higher magnesium requirements due to losses through sweat and increased metabolic demand. High magnesium from diet alone is extremely rare because healthy kidneys excrete the excess efficiently. Elevated levels are most commonly seen with kidney impairment or excessive supplementation. If your magnesium level is outside the expected range, your GP can help identify the cause and advise on whether dietary adjustments or supplementation would be beneficial.