GENEVA — The International Diabetes Federation predicts that one in 10 adults could have diabetes by 2030, according to their latest statistics.

In a report issued today, the advocacy group estimated that 522 million people will have diabetes in the next two decades, based on factors such as aging and demographic changes.

The figure includes both types of diabetes. 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 and said the International Diabetes Federation’s prediction was possible.

Gojka Roglic, head of WHO’s diabetes unit, said the projected future rise in diabetes cases was because of aging rather than the obesity epidemic. 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.