Mercyhealth is offering a free presentation on understanding diabetes. The dinner event will be held Thursday, November 14, 5:30-7 pm, at Holiday Inn Chicago–Crystal Lake, Elara Convention Center, 800 S. Route 31, Crystal Lake. Dr. Tahir Mahmood, internal medicine, Dr. Jakob Thorud, podiatry, and Mary Jo Winkenwerder, diabetes educator, will lead the panel.