Magnesium is a mineral found mainly in our bones (60-65%) and inside our cells (35-40%). Only about 1% of the total amount of magnesium is freely circulating in our bloodstream. This means that measuring magnesium through a blood test is a limited strategy to understand our overall magnesium status.
We need to get magnesium through our diet since we cannot produce it ourselves. It is essential for several functions and processes in our bodies, including the regulation of calcium metabolism important for bone health, the regulation of muscle and nerve function, important for maintaining a regular heart rate and overall muscle contraction and proper function of enzymes required for the conversion of food into energy as well as DNA synthesis.
Normal magnesium levels indicate that you have a healthy magnesium balance in your body, required for the optimal function of various biological processes such as muscle and nerve function, energy metabolism and DNA synthesis.
Measuring your magnesium levels can be relevant for investigating whether or not you suffer from deficiency as an additional tool when showing associated symptoms.
A common cause for wanting to measure magnesium levels is when monitoring treatments that by themselves may cause a change in magnesium levels such as certain diuretics and antibiotics, or when monitoring the treatment of a condition that could affect magnesium levels such as diabetes, kidney disease and gastrointestinal disorders.
Magnesium levels are also relevant to evaluate strict diets lacking magnesium or if you show low calcium or potassium levels, since they correlate to levels of magnesium.
Low levels of magnesium in a blood test suggests deficiency, also known as hypomagnesemia. That means that presumed concentrations of magnesium in the bloodstream is below normal range. The most common cause of magnesium deficiency is insufficient intake of magnesium through your diet.
It is absolutely imperative to consume magnesium rich foods such as leafy greens, whole grains, seeds and nuts to avoid complications deriving from magnesium deficiency. Other possible causes of deficiency are increased excretion of magnesium through diabetes or high alcohol consumption or impaired absorption due to conditions like celiac disease and Crohn’s disease.
Elevated levels of magnesium in your bloodstream, also known as hypermagnesemia, can indicate that there is too much magnesium or that there is a difficulty excreting excess magnesium from your system. Although this doesn’t provide definitive magnesium status, it is an indication that may need to be further investigated.
The most common causes of magnesium excess are kidney dysfunction and excessive intakes of magnesium through supplements and laxatives. Other underlying causes may be hypothyroidism and aldosterone deficiency through adrenal insufficiency.
Important note: Slightly increased levels of magnesium is most often a normal variation and not a sign of disease.