Microwaves destroy nutrients? See what happens to the food

Microwaves work by emitting electromagnetic waves that cause the water molecules in food to vibrate, generating heat and warming the food from the inside out. It is precisely this process that raises questions about possible nutritional losses.

"Microwaves: do they destroy food nutrients? What you need to know before you heat up your lunch": nutrient losses do occur, but not exclusively or exacerbated by microwaving. All cooking methods - whether boiling, baking or frying - cause some loss of nutrients, especially heat-sensitive vitamins such as vitamin C and some B vitamins.

What sets microwaves apart is that, in general, the cooking time is shorter and there is less need for water. These factors, in practice, preserve certain nutrients better than methods such as boiling, which can dissolve vitamins and minerals in water.

• Water-soluble vitamins (such as vitamin C and some B-complex vitamins) are naturally more sensitive to heat and can degrade, regardless of the heating method.
• Minerals (such as calcium, iron and zinc) are more stable and are not easily lost in microwaves.

Therefore, the impact on nutrients is more a question of the length of exposure to heat and the amount of water used than the appliance itself.

To further minimize any nutritional loss, a few simple tips are recommended:

• Use little water when preparing or heating food.
• Choose microwave-safe containers that are free of BPA (Bisphenol A).
• Cook or heat for as long as necessary: avoid overheating food.
• Cover food with a microwave-safe lid to retain steam and cook more evenly.