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Does microwaving food remove its nutritional value?
By Bob Barnett, upwave.com February 7, 2014
The rumor: Zapping food in a microwave leaches out key nutrients.
We've all heard about how microwaving food removes some nutritional value, but is it true? Is something bad happening to our food behind that microwave glass?
The verdict: If you do it right, cooking food in the microwave is one of the best ways to retain your food's vitamins and minerals
There are dangers to microwaving your food. You could get scalded, for one. If you use the wrong kind of plastic (hint: one that doesn't say "microwave safe"), unhealthy chemicals could seep into your food.
But if you're concerned about getting the most nutrition out of your eats, microwaving is a safe bet. In fact, it's near the top of the list for nutritionally sound food-preparation methods. If you use your microwave with a small amount of water to essentially steam food from the inside, you'll retain more vitamins and minerals than with almost any other cooking method.
"Whenever you cook food, you'll have some loss of nutrients," says registered dietician and certified food scientist Catherine Adams Hutt. "The best cooking method for retaining nutrients is one that cooks quickly, exposes food to heat for the smallest amount of time and uses only a minimal amount of liquid."
Guess what? Microwave cooking does that.
Consider spinach. Boil it on the stove, and it can lose up to 70% of its folic acid. Microwave it with just a little water, and you'll retain nearly all its folic acid. Cooking bacon on a griddle until it's crispy (yum) can create nitrosamines, while microwaving bacon creates far fewer of these cancer-promoting chemicals.
Of course, you can mess microwaving up. Dump your veggies in a bunch of water and overcook them, and you'll leach out plenty of nutrition. "When you cook food in a microwave, cover it tightly, creating an efficient steam environment," advises Hutt.
Steaming over a stovetop is just as good, though. In some cases, it may even be better: One small study found that steamed broccoli retained more of its cancer-fighting sulforaphane than microwaved broccoli.
But in most cases, using your microwave to cook food, if it's covered tightly in a microwave-safe container with a minimal amount of liquid, is a nutritional win.
In fact, it can even enhance the nutrition of some foods. It makes the carotenoids in tomatoes and carrots more available to our bodies, for example. It makes the biotin in eggs digestible. And heat kills bacteria in food that can make us sick.
"From a safety standpoint," says Hutt, "you don't want to be eating raw chicken."
So go ahead and use that microwave. It's a quick way to essentially steam food from the inside out. You won't get the aromas that baking or roasting provides, but if you do it right, with just a little bit of water in a tightly-closed microwave-safe container, you'll be very well nourished.
This article was originally published on upwave.com.
Myth: Microwaving Food Destroys Nutrients
By Patricia Bannan FoxNews.com March 08, 2014
This is an old nutrition myth – recently reiterated comically by Jennifer Lawrence’s character in the movie American Hustle – but microwaving food does not destroy nutrients. In fact, according to Kaufman, in some cases microwaving food offers health benefits.
“A fast and convenient way to steam vegetables, microwaving can help people retain more water-soluble nutrients often lost when drowning vegetables in water and cooking them too long. Microwaving also helps preserve heat-sensitive nutrients like vitamin C due to a faster cook time,” Kaufman said.
In addition, partially cooking meat in the microwave means less cooking time over an open flame.
“Microwaving meat before pan-frying or grilling can substantially reduce the formation of potentially cancer-causing chemicals, caused heterocyclic amines (HCAs) and polycyclic aromatic hydrocarbons (PAHs), which cause cancer in animals, and may be linked to colorectal, pancreatic and prostate cancer in humans,” Kaufman advised.
Myth: “Radiation from microwaves creates dangerous compounds in your food.”
“Radiation” might connote images of nuclear plants, but it simply refers to energy that travels in waves and spreads out as it goes. Microwaves, radio waves and the energy waves that we perceive as visual light all are forms of radiation. So, too, are X-rays and gamma rays—which do pose health concerns. But the microwaves used to cook foods are many, many times weaker than X-rays and gamma rays, says Robert Brackett, Ph.D., director of the National Center for Food Safety and Technology at the Illinois Institute of Technology. And the types of changes that occur in microwaved food as it cooks are “from heat generated inside the food, not the microwaves themselves,” says Brackett. “Microwave cooking is really no different from any other cooking method that applies heat to food.” That said, microwaving in some plastics may leach compounds into your food, so take care to use only microwave-safe containers.
Myth: “Microwaving zaps nutrients.”
This is misguided thinking, says Carol Byrd-Bredbenner, Ph.D., R.D., professor of nutrition at Rutgers University in New Brunswick, New Jersey. Whether you’re using a microwave, a charcoal grill or a solar-heated stove, “it’s the heat and the amount of time you’re cooking that affect nutrient losses, not the cooking method,” she says. “The longer and hotter you cook a food, the more you’ll lose certain heat- and water-sensitive nutrients, especially vitamin C and thiamin [a B vitamin].” Because microwave cooking often cooks foods more quickly, it can actually help to minimize nutrient losses.