Zinc is a mineral responsible for a variety of functions in the body. Zinc plays a role in the transmission of nervous system signals and is needed for proper protein and cell membrane structure. The mineral is also found in enzymes, is part of the process that releases hormones throughout the body and helps to regulate cell growth. Zinc occurs naturally in a variety of foods, including meat, poultry, fish, shellfish, eggs, legumes, dairy products, vegetables and grains. The recommended daily allowance for zinc is 11 milligrams daily for adult males and 8 milligrams daily for adult females, reports the Office of Dietary Supplements.
Fortifying foods with zinc oxide helps to ensure that people receive an adequate amount of zinc in their diets. Zinc oxide is added to such foods as flour, breakfast cereal and infant formula. The Ohio State University State University Extension Service reports that most fortified ready-to-eat cereal contains 10 percent of the U.S. recommended daily allowance for zinc. While eating fortified foods helps to increase your daily intake of zinc, the foods might not provide all the zinc that your body needs. If you don’t eat a diet high in foods that naturally contain zinc, you might need to also take a zinc supplement.
The type of food you eat affects how much zinc you absorb in your diet. The highest amounts of zinc are found in fish, poultry, shellfish, eggs and red meat. Although grains and vegetables also contain zinc, less zinc is available from these foods because they also contain phytic acid. Zinc absorption is inhibited when phytic acid is present in a food. Fortification is particularly important in countries where people eat large amounts of plant- and grain-based foods, due to the effects of phytic acid in these foods.
Zinc for Colds
Zinc is often touted as a remedy to the common cold and it is added to some over-the-counter cold medications. A review of 15 clinical trials conducted by the Cochrane Database of Systematic Reviews 2011 found that taking zinc lozenges or syrup is beneficial in reducing the duration and severity of the common cold in healthy people when taken within 24-hours of the onset of symptoms. The review was published in February 2011. Using nasal sprays containing zinc is not recommended, as applying zinc directly to the nose can cause loss of smell.