Article Writing Homework Help

I need help with creating a thesis statement on the role of psychological factors in illness. I originally put

The topic I have chosen is the role of psychological factors in illness. Illnesses of any kind frequently affect much more than just the physical health and well-being, they also affect people psychologically. – it got scored a 0 and the instructor is letting me redo it. I am having problems seeing how else to word it as my thesis statement .