Magnesium is the fourth most abundant mineral in the human body. After potassium, magnesium is the most common cation in our cells. Sufficiently high magnesium concentrations are required for the blood pressure lowering hormone insulin to act on its receptor. Magnesium influences the vascular tone and the release of stress hormones such as norepinephrine. An inadequate supply of magnesium therefore increases the risk of insulin resistance, high blood pressure and cardiovascular diseases. Magnesium is mainly found in plant-based foods. Because of their lower calorie density, our ancestors‘ diet contained significantly more magnesium before the beginning of agriculture. In addition to an unbalanced diet, a magnesium deficiency is promoted by certain diseases and the use of various medications.