Only 0.003% of your body is zinc, but without it, you would not be able to live. The amount we need is relatively small compared to the effect it has on the body, in fact scientists are continuing to uncover new roles for this essential mineral.
Zinc intake has declined over the last 60 years
Our zinc intake has declined over the last 60 years, due to changed eating habits, including a reduction in the amount of red meat we are eating - in fact we are now consuming less zinc than during rationing in World War II. The World Health Organisation estimates around 2 billion people are of low zinc status worldwide.
Dietary zinc intake can be a guide to an individual’s zinc status, but the amount of zinc that is absorbed by the body will depend on the type of foods eaten - the search for a good indicator of zinc status is currently on-going.
How Zinc is used in the body
There are many ways in which Zinc is used in the body:
- Structural: zinc holds proteins together like staples ensuring they are facing the right way to do their job. A lot of these proteins control the reading of our gene blueprints to make new proteins.
- Activation of enzymes: for example alcohol dehydrogenase (a zinc requiring enzyme) breaks down alcohol.
- Signalling: zinc can trigger a chain reaction within a cell which can help it to survive in response to a stimulus such as inflammation and stress from free radicals.
Affects of Zinc deficiency
Zinc deficiency affects:
- immune function
- spatial navigation and memory
- mood and depression
- cardiovascular health
It could be said that there is somewhat of an advice paradox when it comes to obtaining Zinc through diet - a common perception is that red meat is bad for the body and bad for the environment so one is compelled toward 'healthy choices' of fruit and vegetables. With the former rich in zinc and the latter containing very little it's difficult to know what to do. The best compromise is to eat some lean red meat each week alongside plenty of fruit and vegetables, cereals and pulses. The Department of Health suggests that up to 90 grams of lean red meat per day is safe.
Furthermore it's important to note that some plant foods such as cereals contain a natural compound that can reduce zinc absorption by your gut, so while some of these foods may be reasonably good sources of zinc, the amount of zinc extracted by your body may be lower than with animal foods.
How much do you need?
The recommended daily intake in the UK is 7.0mg per day for adult women and 9.5 mg per day for adult men. Please note you should not take more than 25 mg a day as very high intakes can be harmful to the body.