By Lisa Rapaport (Reuters Health) – Some families gathering for Thanksgiving this week may have something to argue about besides politics: what to do when teens at the table follow a different diet than everyone else. One in six U.S. parents say their teen has tried a diet that is vegetarian, gluten-free, vegan or paleo at some point in the last two years, according to a poll released today by the University of Michigan in Ann Arbor. It may be tempting to argue about food or push children to join the clean plate club, but parents should try to understand why their teen wants to skip family favorites like turkey, sweet potato and marshmallow casserole or apple pie, said Sarah Clark, co-director of the C.S. Mott Children’s Hospital National Poll on Children’s Health.