Having normal potassium levels in the body is important because potassium is necessary for proper functioning of muscle cells and maintaining fluid balance and healthy blood pressure, and it helps regulate heartbeats. A mineral and electrolyte, it may decrease the risk of kidney stones and in older people also reduce the risk of bone loss. The most common reason for low potassium, or hypokalemia, is taking certain medications. Other causes include excessive alcohol drinking, kidney disease, and folate deficiency. Potassium-rich foods include bananas, mushrooms, potatoes, peas, cooked broccoli and spinach, and pumpkin.
Vitamin A is crucial for eye health. In fact, vitamin A deficiency (VAD) is the leading cause of preventable blindness among children, according to the World Health Organization. The main cause for VAD is prolonged inadequate intake of the vitamin. Foods that are rich in vitamin A include green and orange vegetables such as leafy greens and carrots, as well as eggs and cantaloupe.
Vitamin E acts as an antioxidant in the body, protecting cells from damage caused by free radicals, which are compounds formed when we digest food as well as by cigarette smoke, air pollution, and UV rays. The vitamin also strengthens the immune system and keeps blood from clotting. Vitamin E is naturally found in sunflower, almonds, and green vegetables such as spinach and broccoli. Some foods, including fruit juices and breakfast cereals, are fortified with vitamin E.
Copper deficiency is more common among people with untreated celiac disease than the general population. It is sometimes confused with anemia but is now more frequently recognized as its condition. Good food sources of copper, which is important for heart and bone health as well as a strong immune system, include shellfish, whole grains, beans, nuts, potatoes, organ meats, dark leafy greens, dried fruits, cocoa, black pepper, and yeast.