Zinc is a mineral and an essential nutrient that plays a role in growth and development, the production of insulin, efficient metabolic processes, hair growth, immunity, fertility, the proper development of a fetus, and the senses of taste and smell.
Zinc occurs naturally in many foods, including red meat, poultry, some shellfish, whole grains, beans and nuts. While zinc is present in plant foods, they are not as easily absorbed by the body as the zinc that is found in meats and shellfish. In fact, oysters are the number-one source of zinc found in food.
It's important to note that a maintaining a regular, steady intake of zinc is vital to good health because the human body does not have a mechanism to store zinc for later use. It is recommended that most zinc consumption should come from natural food sources. However, zinc supplements can be helpful, especially when illness threatens.
Zinc is known to aid in strengthening the immune system, which is the human body's first line of defense against illnesses, diseases and infections. It is also helpful to add zinc to the diet when ill with a cold or flu to promote a quicker recovery. In addition, zinc is known to aid in the healing of sore throats, which is why it is frequently found in sore-throat lozenges as well as non-prescription cold medicines.
As with just about everything, there is a down side to ingesting too much zinc. For example, people who overuse zinc-containing nasal sprays have been known to lose their sense of smell, sometimes permanently. Because of this danger, and a June 2009 FDA warning, manufacturers of these nasal sprays have voluntarily withdrawn their products from stores.
Consuming more than the daily recommended dosage of zinc can also cause diarrhea, nausea and vomiting, as well as the lowering of good cholesterol, and it may even lead to decreased immune function.
These side effects should be kept in mind when adding a zinc supplement to a healthy diet. Although zinc is required for the human body to function properly, it is important to follow the recommended daily dosage indicated on supplement packaging to avoid any harmful side effects.