Zinc is an essential trace mineral which means we get what we need via the food we eat but the amount required is fairly small. That said, it is crucial for human functioning and is found in every cell in our bodies. It's role in wound healing dates back to the ancient Egyptians.

Where do I find zinc?

We get zinc from our diets or by taking supplements or multivitamins. Rich food sources include: oysters, other shellfish, dairy products, meats, grains and pulses. Men need between 5.5-9.5mg a day, and women 4-7mg daily.

Why do I need zinc?

Zinc plays many important roles. It supports the immune system and wound healing, reproduction, vision, blood clotting, insulin production, the processing of carbohydrates, fats and proteins from food and aids smell and taste. Zinc also has antioxidant properties helping to protect our cells from damage from free radicals. Free radicals are thought to contribute to ageing and conditions such as heart disease and cancer. Zinc also seems to be good for the skin and some experts believe zinc supplements can improve acne.

Furthermore, some experts believe Zinc slows down the progression of the eye disease age-related macular degeneration. You'll often find zinc in supplements that aim to boost immunity and fight colds. Although studies are mixed there appears to be some evidence that zinc supplements may lower your risk of contracting a cold and reduce the length and severity of any cold you do catch.

Zinc cream is sometimes used to reduce symptoms from cold sores. Zinc is also linked to healthy sperm production - which may explain why oysters, which are one of the richest sources of zinc, are considered to be an aphrodisiac.

How will I know if I am lacking in zinc?

A zinc deficiency is rare but sometimes occurs in elderly people, alcoholics, people who are malnourished or anorexic and those on very restricted diets. Those with gastrointestinal conditions such as Crohn's disease may also struggle to absorb all the zinc they need.

Signs of a deficiency include weight loss, loss of taste and smell, poor wound healing, bad skin, hair loss, weak fingernails, lack of appetite, night blindness, depression and lack of a menstrual period.

Can too much zinc be harmful?

Like all trace elements you only need a small amount of zinc. Too much zinc can cause a copper deficiency as it reduces the amount of copper the body absorbs. While you only need copper in small amounts it plays an important role in the production of red and white blood cells and helps with infant growth and immunity. If you want to take zinc supplements you may want to combine this with a copper supplement (of around 1.2mg). Too much zinc can also cause stomach irritation, nausea and vomiting.