A sizable number of older Americans are addicted to junk food, according to a new survey from the University of Michigan. The survey, conducted as part the university’s National Poll on Healthy Aging, found that one in eight adults between the ages of 50 and 80 met the criteria for addiction to highly processed food items, such as sugary sodas, chips and fast-food fare. The University of Michigan pointed to the obvious reason for concern over addiction to junk food.