DEAR DR. FOX: Our 8-year-old Lhasa-poodle mix is a bit overweight, so we started giving him diet dog food. He’s lost 3 pounds, but for the past week, each time he eats his dog food, he vomits it back ...

We have an 8-year-old Lhasa-poodle mix that we love. He is a bit overweight, so, for the past few months, we've been giving him 1/2 cup of Purina Fit and Trim Healthy Weight Adult Dog Food twice a day ...