Is Microwaved Food Bad For Us?

ALTHOUGH the technology had been around for a while, it wasn't really until the 1980s when microwave ovens really started to become a regular feature in most UK kitchens, offering a quick and easy way to cook and heat food.

Many people hailed it as the best thing since sliced bread (not my favourite loaf form, but that's another story) and manufacturers rushed to provide us with essential utensils, exclusively for use with microwaves, cookery books which demonstrated how to produce entire meals using only the microwave and 'ready meals' specifically designed for re-heating in the microwave.

In fact some enthusiastic advocates went as far as declaring that the microwave was the only piece of equipment that 20^th century man and woman needed in the kitchen. Except, presumably, a pair of scissors and a fork.

So, with a few decades-worth of use under our belts, how does microwave cooking compare with conventional cooking?

An early microwave

How does it work?

Essentially, microwave ovens transmit heat via electromagnetic radiation, which travels through the food container and causes water molecules in the food to vibrate and heat up. It's quicker than conventional cooking, which heats the container first and then the food, but it's harder to control how and where heat is directed.

Is it safe?

• Radiation - The design of modern microwave ovens means that they are equipped with safety switches that turn off the radiation when the door is open and ovens are sufficiently insulated to allow only what is described as 'minimal leakage' when the oven is working. However, it's important to remember that the type of radiation used by a microwave is not the same as the radiation used by, for example, X-rays.
  
  
• Food poisoning - There is a risk that, because foods can heat unevenly, there may be a greater risk of food poisoning when using a microwave (have you ever been served lasagne in a restaurant that looks cooked on the outside but is stone cold when you cut into it?). Following instructions such as stirring the food, letting it stand in between blasts and checking that it's piping hot all help to minimise the risk.
  
  
• Heat - there have been many reported incidences of people scalding themselves after heating food or drinks in the microwave. Make sure that you don't overheat foods - and especially drinks - and allow them to stand before tucking in. The NHS advises against heating babies' bottles in the microwave as uneven heating may scald baby's mouth.

Is there anything you shouldn't heat in the microwave?

• Whole eggs - as they will explode.
  
  
• Babies' bottles - see above.

Microwave Cooking For One

Is it healthy?

• Nutrient content - There are only very limited studies into the effects of microwaving and the nutrient content of foods so it's difficult to be definitive. The vitamin and mineral content of microwaved vegetables appears to be about the same as cooking them conventionally but there are some question marks over the effects of microwaving on proteins. I would say the jury is still out.
  
  
• Plastics - Much of the heating done in microwaves is done in plastic containers and often uses plastic coverings such as cling-film. There is increasing evidence that compounds in the plastic called, unsurprisingly, 'plasticisers' can leach into foods, especially fatty foods, when they are heated. These compounds are believed to cause hormone disruption in humans and may be linked to numerous hormone-related health issues, including some cases of obesity.

Should we be using microwaves?

When weighing up the advantages against the disadvantages, an important consideration is what kind of foods are we heating in microwave ovens? The problem is that, very often, they are used to heat up ready meals, which are often relatively low in nutrients in the first place.

However, in some situations, eg., if you work at a site with limited access to shops and canteen facilities, bringing in a homemade soup and heating it in the microwave may be the only way you can get a decent meal in the middle of the day.

Personally, I prefer to cook using more conventional means. It's tried and tested and there's lots of research that tells me how cooking methods, such as steaming, preserve the nutrient content of foods. I enjoy taking the time to choose and prepare what I am going to eat and I think the food tastes better for it.  Even when I'm in a hurry, an omelette and a side-salad or a piece of poached fish with some steamed vegetables takes little more time than bunging something in the microwave and yet the taste and texture is immeasurably better.