This research review examines the critical role of magnesium in preventing various chronic diseases. Magnesium's involvement in over 300 metabolic reactions, including those related to energy production, nerve transmission, and blood pressure regulation, is highlighted. The review presents evidence linking low magnesium levels to conditions such as migraine headaches, Alzheimer's disease, stroke, hypertension, cardiovascular disease, and type 2 diabetes. Dietary sources of magnesium are discussed, with an emphasis on whole grains, leafy green vegetables, and surprisingly, white potatoes. Finally, the paper summarizes existing research on magnesium supplementation as a potential treatment for several of these diseases.