Sodium and potassium were discovered together and both found to be essential for normal growth. Sodium is necessary for maintaining the proper water balance and blood pH. It is also needed for stomach, nerve, and muscle function. Adequate sodium in the blood aids in keeping calcium and other minerals in the blood soluble. Although a sodium deficiency is rare, its symptoms include confusion, low blood sugar, weakness, dehydration, lethargy, and heart palpitations, and are more likely to occur in warm/hot weather and/or during strenuous exercise, work and heavy perspiration. Excess sodium intake results in edema, high blood pressure, potassium deficiency, and liver and kidney disease. Sodium intake may lead to heart disease when not properly balanced with potassium. Food Sources: Virtually all foods contain some sodium, but most abundant in table /sea salt, shellfish, carrots, beets, artichokes, dried beef, brains, kidney, bacon. Herbal Sources: Alfalfa, burdock, cayenne, coltsfoot, eyegright, fennel, garlic, irish moss, kelp, mullein, nettle, parsley, plantain,raspberry, sage, shepherd's purse, thyme. Supplementation: Rarely needed, but if so, kelp is a safe and nutritive supplement . There is no official allowance, but a daily single gram of sodium chloride has been suggested for each kilogram of water drunk.