I think they are bad only if you eat too much. Carrots are rich in vitamin A and if you take in too much your skin may turn yellowish. Eat moderately and they will be great for the skin.
Carrots are excellent for the skin. A guy drank about 6 cups of carrot juice a day and turned completely orange, he loved the stuff. But I have to say his skin texture was gorgeous, too. Limit the intake but know that they are very beneficial for you.