Mom always said that when you peeled a vegetable you were throwing out most of the nutrients. Some dishes are okay with the peeling left on, others will look awful. In an article for First magazine, Chef Roberth Sundell suggests that you boil the veggies with the skin on and then peel them to get the most benefit. He says about half of the nutrients in the skin will soak into the veggie itself and as a bonus you can peel them easier. I tried this with potatoes. The skin comes off much more easily which saves time and there is less waste.