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Does microwaving food make it less healthy?

The internet is home to countless blogs and articles claiming that microwaves are bad for our health. The usual accusations are that they are responsible for removing vitamins and nutrients from our food. However this notion that microwaves are worse for us than other forms of cooking is not supported by scientific evidence.

Microwave ovens use microwave radiation to heat food. The microwaves cause the water molecules in the food to vibrate, generating heat that spreads through the surrounding molecules to heat, and hence cook, the food. This process can affect the vitamins and nutrients in our food but these changes are not unique to microwave cooking – it’s a result of the heating.

When food is heated some vitamins, such as vitamin C, can be broken down, but this is a product of the heating process and will happen regardless of whether the food is cooked on a hob, in a conventional oven or in a microwave.

Proteins are also ‘denatured’ – it’s a term that sounds like ‘the naturalness is being taken out’ but just means that the proteins are being broken down, and it happens when they are heated by any means of cooking.

Another way that nutrients can be lost is by cooking food in water – studies have shown that boiling vegetables allows nutrients to leak out into the cooking water – which is then usually thrown away. This means that greater nutritional losses are recorded with boiling than with steaming or frying – or microwaving.

In fact, the best way to retain vitamins and nutrients when cooking is to use short cooking times that limit the exposure to heat and a cooking method that uses as little liquid as possible – two things that are easy to achieve with a microwave, although studies show that the very best way to retain nutrients in vegetables is to steam them.

So if you like using a microwave – carry on! In some cases your food might actually be more nutritious!