Oh, and frozen veggies aren't less good for you than fresh. Not really.
Here's the deal: Microwave ovens use radio waves specially tuned to excite water molecules. Since these molecules all bounce around and heat up at the same time, your food cooks more quickly than with other methods, where molecules get excited from outside in.
Metal reflects these radio waves, which is why you're in for quite the light show if you accidentally put a fork in there. But that well-known explosive reaction is actually a reminder of how safe microwaves are: The metal they're lined with keeps any of the radio waves from escaping into your kitchen. FDA regulations keep microwaves from emitting anywhere close to enough radiation to hurt a human-- even if that human is pressed up against the glass watching a marshmallow bunny implode.
But microwaves aren't just safe. They might actually be the healthiest way to cook food. See, microwaves let you cook your food without any oils or other fats, so they keep the meal leaner. Plus they involve a lot less water. That's great from a conservation standpoint, but it's also good news nutritionally: When you boil vegetables, the water you dump out at the end carries some valuable nutrients with it. Because most veggies can go in the microwave with just a smidgen of water, there's less chance of wasted vitamins and antioxidants.
And those veggies you nuke needn't be fresh to be healthy. Frozen veggies are locked at their peak freshness, which is also when they pack the biggest nutrient punch. Vegetables you buy at the store may have been sitting around long enough to have lost some of their nutritional value. Certain nutrients are still best when fresh, but lots of frozen produce is just as good for you -- if not better -- than what you'd typically pick up in the fresh produce section.
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