It's easy to get answers about health and nutrition! Just send your question by email to firstname.lastname@example.org and Dr. Harlan will respond to selected questions of general interest. Answers will be posted in the Ask Dr. Gourmet newsletter (sign up now!) and archived in the Ask Dr. Gourmet section of the website.
While recently attending a home show, I watched a demonstration of waterless cookware. The chef and salesperson indicated that their cookware preserved maximum vitamins in cooking fresh vegetables. They made the statement that microwaving fresh veggies almost instantly destroys up to 95% of the nutrients. I was stunned as I love to cook my naked fresh veggies to a crisp-tender in the microwave. Any opinion or research on this?
This is an urban myth (a nice way of saying that the huckster was trying to sell you a stupid product).
All cooking processes will change micronutrients, whether the food is boiled, fried, broiled, or microwaved. The less you cook an item, the less nutrient loss there will be.
Microwaving food does result in nutrient loss and there are many studies about this (too many to cite). Most show that there is less loss of micro- and macronutrients than with other methods of cooking, however.
"Effect of microwave cooking or broiling on selected nutrient contents, fatty acid patterns and true retention values in separable lean from lamb rib-loins, with emphasis on conjugated linoleic acid." Food Chemistry
"Influence of Cooking Methods on Antioxidant Activity of Vegetables." Journal of Food Science
This latter study is pretty amazing, with scientists looking at the effects of multiple cooking methods on a variety of different vegetables. The microwave cooked veggies actually came out best, with over 97% of the antioxidants being preserved.
I don't use the microwave a lot, but I do use it, and the research is clear. It does not harm your food by making it radioactive or less nutritious.
Thanks for writing,
Timothy S. Harlan, MD, FACP