An aging population and demographic changes could mean that one in 10 adults could have diabetes by 2030.
The latest statistics from the International Diabetes Federation estimate that 522 million people will have diabetes, either Type 1 or Type 2, in the next two decades.
The group expects the number of cases to jump by 90 percent even in Africa, where infectious diseases have previously been the top killer.
According to the World Health Organization, there are about 346 million people worldwide with diabetes, with more than 80 percent of deaths occurring in developing countries. The agency projects diabetes deaths will double by 2030.
Most cases of diabetes are Type 2, the kind that mainly hits people in middle age, and is linked to weight gain and a sedentary lifestyle.
WHO says a substantial number of future cases are preventable.