I’m sure most of us keep a can of baked beans in the cupboard for emergencies or use tinned tomatoes in our cooking. But are they good for our health?
Why Can Food?
Canned food has been around for quite some time. Back in the early 1800’s a French confectioner called Nicolas Appert discovered that if you put food in a glass jar, boiled it, and sealed it, the food wouldn’t go bad. His discovery was a godsend to the French Government who had challenged citizens to find a way of preserving food so that they could feed their soldiers properly. This method of preserving quickly caught on and soon a British man called Peter Durand tried using tin cans instead of breakable glass bottles to store the food, so that by 1839 canning food was a common occupation.
How Does It Work?
To preserve food in this way, the can needs to be sterile, air-tight, and vacuum-sealed. The food is also heated to temperatures high enough to kill any bacteria that could otherwise affect the food.
Is Canned Food Safe?
Canned food is thought to be one of the safest methods of preserving food as long as the tin is not damaged and remains fully sealed and air-tight.
Cans have a long shelf-life (of at least two years), without the food deteriorating, and vitamins and proteins are thought to remain stable whilst in the tin.
Even so, many foodstuffs are preserved in sugared or salted water which in themselves are not healthy, but if you are careful to select food stored in its own juices or in water, then you need not feel guilty for falling back once in a while on a tin of soup rather than making it from fresh ingredients.
Metals In Cans
Whilst the preservation technique of canned food is sound, and the food doesn’t deteriorate significantly in quality, there are some concerns about the metal that the cans are made from. Cans have also traditionally been called ‘tins’ because they used to be made of steel-coated tin. Today, they are more often made from lacquered steel or aluminium.
It’s possible that some acidic foods, such as tomatoes and fruits, could react with the metal in cans, so cans which hold these types of food are usually lined.
As modern cans often contain aluminium, there has been some concern as to whether the metal could leach into the food it contains.
The worry is due to circumstantial evidence which indicates that aluminium could be a contributing factor in the development of Alzheimer’s disease. Nevertheless, scientists argue that the amount aluminium which would enter the food from the can is negligible and the tins are now lined with plastic to help prevent this possibility.
Plastic Linings In Cans
However it is this ‘protective’ polycarbonate plastic lining which has recently caused the most controversy.
The plastic lining which is used on the inside of many cans contains a chemical called Bisphenol A, or ‘BPA’. BPA is a toxic chemical compound which has been linked to disruption of the endocrine system as well as prostate and breast cancers.
Exposure to BPA in animals has been shown to have devastating effects including infertility and metabolic syndrome and seems to have the same oestrogenic effects in humans.
Bisphenol A in Canned Food Tests carried out on foods which contain BPA coatings, have shown to have alarmingly high levels of the chemical in the juices, with cans of peas containing the most.
While there are limits set in Europe for the amount of BPA used in the linings of cans, many environmentalists feel that no amount of BPA is safe. Of particular concern is the fact that other countries have not legislated for maximum amounts of BPA in tins or cans and so levels many times the amounts deemed ‘safe’ are being found in food and drinks.
What You Can Do If you are worried about the use of BPA in canned food, switch to bottled preserved foods, fresh food, or cans not lined with plastic.