Testosterone levels generally decrease as an individual ages. This is normal and natural, but it can lead to erectile problems for some people because androgenic hormones such as testosterone play an important part in regulating the function of tissues in the penis and testicles. One study found that supplementing with testosterone gel improved both the libido and erectile function of participants with low testosterone between the ages of 32 and 84.
Zinc is a trace metallic element that occurs naturally in the earth. Certain vegetables, meats, and seafood have more zinc content than others. This makes it fairly easy to obtain zinc through a varied diet. An extreme zinc deficiency is rare in the United States, as most people get some zinc through the foods that they eat. However, when levels of zinc fall below the recommended threshold, problems begin.