Why there’s been a dangerous diabetes spike around the globe

According to a new study from the World Health Organization, diabetes cases have quadrupled over the last 40 years, mostly in poorer nations. Today, 8.5 percent of all adults worldwide suffer from the chronic disease, and 3.7 million deaths are linked every year. For more on the emerging health crisis, William Brangham talks to Dr. Etienne Krug of the World Health Organization.