The Gallup-Healthways Well-Being Index said the 10.6 percent figure recorded in the second quarter was among the lowest levels recorded since 2009. The diabetes rate was below 11 percent throughout 2008, but then began to increase in 2009 and 2010, Gallup officials said.
The obesity rate, which has a well established relationship with type 2 diabetes, also declined slightly in the second and third quarter of this year -- with somewhat lower levels in 2011 compared with 2010, Gallup said. Gallup measures the obesity rate based on respondents' self-reported height and weight.
The slight downward trend in obesity levels could be related to similar trends in diabetes rates during the same time period, Gallup officials said.
Gallup said obese Americans are nearly three times as likely as those who are not obese to report having been diagnosed with diabetes, and states with the highest obesity rates have much higher diabetes levels than those with the lowest obesity rates.
Gallup-Healthways Well-Being Index surveys at least 1,000 U.S. adults a day, approximately 84,000 adults per quarter. The survey has a margin of error of 0.3 percentage points.