Then, Gallup offered an observation from its Healthways Lifestyle Solutions Director, Janna Lacatell.

"To date, most efforts to curb obesity focus on driving weight loss through diet and exercise, without addressing other aspects of well-being that may contribute to obesity," Lacatell said. "The rising obesity rate suggests these efforts have been largely ineffective. While access to evidence-based, proven weight loss programs emphasizing better nutrition and more physical activity is a critical component to reducing obesity, these interventions alone are not enough. To make a truly measurable impact on reducing obesity rates, interventions should also address other factors known to influence weight management, such as financial and social well-being."

Now, to the details of the survey that led to Gallup's conclusions.

Obesity among U.S. adults has increased more than 2 percentage points since 2008. "More Americans who were previously overweight have now moved into the obese category, while the percentage who are at normal weight has remained stable since 2013," the polling firm reported.

Read: Americans ambivalent about losing weight

Most of the increases found in various groups were only marginal in 2014, suggesting that perhaps some of the attention focused on the issue has helped.

Still, some demographic groups presented worrisome increases.

"Since 2008, Americans aged 65 and older have seen the sharpest uptick in obesity, a four-percentage-point increase to 27.4 percent," Gallup reported. "This is followed by increases among 45- to 64-year-olds (3.5 points), Americans living in the Midwest (2.9 points) and women (2.8 points).

The good news: "Obesity rates among Hispanics, blacks, and young adults aged 18 to 29 are similar to those found in 2008." They haven't dropped, but at least they haven't gotten worse.

African Americans reported the highest rate among racial groups: 35.5 percent. Young adults and those in the higher income brackets report the lowest incidences of obesity.

Gallup then compared results from its well-being surveys to those from the obesity poll. (Gallup has its own well-being index.) Here's what shook out:

"Americans of a normal weight have the highest average well-being [index] (64.5), followed by those who are overweight but not obese (63). Underweight Americans (62.2) have lower well-being than those who are overweight. Americans who are obese have the lowest well-being across weight groups."

Gallup concluded that obesity should be addressed from a holistic approach rather than the diet-and-exercise strategy that has prevailed until now.

"Addressing the underlying causes of obesity through a better understanding of all elements of well-being can help more Americans achieve a long-term healthier weight," the report said.