(crossposted to Safe Happy Healthy Blog)

As I’ve gotten more nutrition conscious and doing what I can to ensure that the food we eat is nutrient-dense, the question of microwaves has been on my mind. Does microwaving our food kill it? Are the nutrients zapped right out? I have felt (without actual evidence) that microwaving probably does remove nutrients. I’ve gradually moved away from thawing, reheating or cooking most food in the microwave. However, statistics show that 90% of us here in America own and use our microwaves. So my question to myself lately has been, am I just cheating myself out of easier meal preparations? So, you know what happened next… I pulled on my research hat and hit the internet. Here’s a little of what I found:

Oh No - The Nutrients Go!

One of the first things that made me think that microwaving wasn’t good for food was the article that came out earlier this year about microwaving your damp sponges to kill bacteria and viruses. Quick cook your sponge on high heat for 2 minutes and it will kill living germs, bacterial spores, and even E.coli. (Quick tip: don’t do this with a dishcloth or dry sponge - you may end up with a fire on your hands.) This is all well and good - but if it kills all that, how do the natural vitamins, minerals, enzymes, and phytonutrients survive those same two minutes?

Traditional cooking methods heat the food from the outside. Microwaves, on the other hand, cook the food from the inside out. The microwave converts electricity into high frequency microwaves. Microwaves are electromagnetic energy. When microwaves are used on food it causes the food molecules to vibrate rapidly, creating friction. The friction produces heat that cooks the food. Those who believe microwaving destroys the nutrient value of our food say that this intermolecular friction destroys the cellular structure of food and can even change the chemical composition so much that it becomes something that the body can no longer recognize as food.

One of Discovery Health.com’s Nutrition Experts Dr. Allan Spreen says this:

“What studies exist are all bad news for microwaving – they universally describe some type of damage. One study showed breakdown of vitamin B-12 to inactive degradation products in microwaved foods. There’s also a problem with release of potentially toxic molecules into the food from packaging designed to help brown food during microwaving. This includes items such as pizza, French fries, waffles, popcorn and breaded fish.” (*Source)

The November 2005 issue of the Journal of the Science of Food and Agriculture stated that:

The first study found that the simplest cooking method was also the worst when it came to preserving nutrients. Broccoli lost 97 percent of flavonoids, 74 percent of sinapics and 87 percent of caffeoyl-quinic derivatives (three different types of antioxidants) when it was microwaved.

Keep in mind, some nutrients were lost when boiled the conventional way as well — although not as much. See complete article for more details.

Zap-a-dap, Cooking’s a Snap!

Dr. John McDougall, M.D. is a highly respected alternative, nutritional medicine doctor who promotes steering clear of animal products including dairy and eating a vegetarian diet of whole grains, legumes and vegetables. He was quoted in 2001 to say:

He says he’s found that microwaving “doesn’t do anything worse to the food than conventional cooking.” He confidently adds, “I like to make sure all of the things I fight are worth fighting against. And as far as I’m concerned microwaves is not where the enemy is at.”
(*Source)

However, a 2005 newsletter on Dr. McDougall’s website seems to point to the fact that he’s not certain. In that newsletter he says “more research needs to be done on the safety of microwave cooking. From what I can tell, he still suggests people use the microwave in his cookbooks. So he, for one, isn’t convinced that microwaves are bad.

As of March 2005, Australian’s largest and most diversified food research organization, Australia Food Science promotes microwaves ovens as a convenient and healthy way to cook. Nutritionist George Rapitis, Bsc says “steaming veggie in the microwave can best preserve their nutrients…” The UK Nutrition & Food Science Journal published an article in 1995 stating:

Several studies have shown that microwave cooking, if properly used, does not change the nutrient content of foods to a larger extent than conventional heating. In fact, suggests that there is a tendency towards greater retention of many micronutrients with microwaving, probably due to the shorter preparation time. Does not describe non-thermal effects. The main problem with microwaving is the uneven heating of the food, which has raised concern regarding microbiological safety. Microwaving infant formula and breast milk has become increasingly popular. The content of nutrients and antibacterial factors in milk are maintained unchanged provided the final temperature does not exceed 60°C (140°F).

Once Everything’s Been Baked

It’s clear there is no consensus yet. The only general agreement I could find is this… cook your food as little as you can. The less cooked it is (no matter what method you use), the better for you it is.

And what did I decide? The microwave may stay around because I share a home with my parents. For me, though, I’m done with the microwave. I’m going to get a counter top convection oven. I’ve mostly weaned myself away from the microwave already… I don’t believe it will require much more effort to go the rest of the way.