Micorwaves alter the molecular structure of food and water. So your body can not utilize it properly. That is the simple answer.
I heat my water in the AM at home for 2 minutes on the stove and add lemon and apple cider vinagar and tad of Sea Salt . At work I mostly drink Yogi tea. Im not crazy about plain warm water. I just tried the Water Cure (adding salt to your water) today and it is sooooooooooooooooooooooo bad. I wont do that again. But it is ok with lemon juice in the morning.