Diarrhea, hair loss, delayed wound healing, impotence and problems with growth, development and the immune system are symptoms of zinc deficiency, reports Mayo Clinic. Eye and skin conditions, weight loss, loss of appetite, taste and smell changes, and mental slowness are also possible. Severe zinc deficiency is still found in developing countries and can be caused by insufficient intake, poor absorption or increased excretion of zinc.
Although zinc deficiency is rare in developed countries, elderly and pregnant individuals sometimes experience it, notes Mayo Clinic. This trace mineral is found in bones, muscles, kidneys, the liver and retinas and is essential for multiple bodily functions. The best dietary sources of zinc include legumes, peanuts, shellfish, beef and pork. As of 2015, the recommended dietary allowance in supplement form is 8 milligrams daily for females age 19 and older, 11 milligrams for males 19 years old and older and pregnant women, and 12 milligrams daily for lactating women 19 and older.
Studies show zinc gluconate and zinc sulfate effectively treat acne, according to Mayo Clinic. Zinc sulfate taken in daily doses of 10 to 200 milligrams improves immune response in individuals with HIV/AIDS. Zinc also helps reduce symptoms of attention deficit hyperactivity disorder in children, such as hyperactivity and impulsivity. Zinc treats sickle cell anemia by increasing weight, height and testosterone levels and improving immune system functions.