GNC intends for its potassium and magnesium aspartate supplements to be used to regulate water balance and support nerve and muscle cell function in the body. The company cites research data from Aisle7 suggesting that potassium lowers blood pressure, treats congestive heart failure, prevents strokes and reduces cardiac arrhythmias. Potassium was also shown in a preliminary trial to resolve symptoms of premenstrual syndrome in women.
GNC notes that potassium and magnesium aspartate treatment improved symptoms in people with chronic fatigue syndrome in some trials. A potassium deficiency can cause high blood pressure, stroke, digestive disorders and cancer, according to WebMD. It has also been linked to heart disease, arthritis and infertility. People who use diuretics and some forms of birth control can suffer from a potassium deficiency. It is also common for athletes and people who work in physically demanding jobs to lack potassium.
Digestive disorders such as Crohn's disease, eating disorders, smoking and alcoholism can lead to a potassium deficiency as well. WebMD states that a magnesium deficiency occurs when the mineral is depleted by the body faster than a person's diet can replace it. This occurs most often as a result of water pill use. Malnutrition, alcoholism, diarrhea, vomiting and diabetes can also cause a magnesium deficiency.