I found a couple interesting Dr. Mercola articles:

These articles claim that microwave cooking makes food more carcinogenic, decreases food value by destroying nutrients, and creates unnatural substances that shouldn’t be consumed by humans. Listed side effects of eating microwaved food include long-term brain damage, altered hormone production, tumors/cancer, a weakened immune system, memory loss, and decreased intelligence.

Sounds like the same list of negative side effects of other things I’ve stopped putting in my mouth — animals, dairy, eggs, fluoride, etc. Perhaps it’s time for me to reevaluate my microwave oven usage as well. I actually don’t think it would be that hard for me to do without it.