2tional Diabetes Statistics Report, 2017 | Na. Results. Prevalence of Both Diagnosed and Undiagnosed Diabetes • An estimated 30.3 million people of all ages—or 9.4% of the U.S. population—had diabetes in 2015 (Methods). • This total included 30.2 million adults aged 18 years or older (12.2% of all U.S. adults), of which 7.2 million (23.8%).