Overweight and obesity continues to be a considerable healthcare and societal burden despite the fact that it can potentially be averted. “These conditions have been linked to many other chronic health issues, including type 2 diabetes, heart disease, certain cancers, and arthritis,” says Graham A. Colditz, MD, DrPH.
About 20 years ago, the prevalence of overweight and obesity in the United States were estimated using a nationally representative data set from 1988-1994. For a study published in JAMA Internal Medicine, Dr. Colditz and colleagues used the most recent information from the National Health and Nutrition Examination Survey (NHANES, 2007-2012) to update overweight and obesity data by sex, age, and race/ethnicity and compared the findings with those of the earlier study.
Investigators aggregated NHANES data from 2007-2008, 2009-2010, and 2011-2012 datasets and included only adults who were 25 or older. Patients’ BMIs were used to classify patients as underweight (<18.5 kg/m2), normal weight (18.5-24.9 kg/m2), overweight (25.0-29.9 kg/m2), obesity class 1 (30.0-34.9 kg/m2), obesity class 2 (35.0-39.9 kg/m2), and obesity class 3 (≥40 kg/m2).
According to the results, about 40% of men in the U.S. (more than 36 million) are overweight and another 35% (about 32 million) are obese. For women, 30% are overweight (nearly 29 million) while approximately 37% (about 36 million) are obese. “The weight status distribution was similar for both men and women across almost every racial group,” adds Dr. Colditz. “However, when compared with data from 20 years ago, the greatest increase in the proportion of patients in the obesity class 3 category was among non-Hispanic black women.”
The rising trends in overweight and obesity warrant attention from health policy and healthcare system decision makers, according to Dr. Colditz. In clinical practice, efforts for preventing and treating chronic conditions have focused primarily on screening high-risk populations. As a result, people in higher-weight categories are more likely to be diagnosed with the chronic diseases linked to excess weight due to more frequent measurements. This approach may ignore people with normal weight and their weight gain.
“Obesity is one of the biggest contributors to shortened life expectancy because it is driving increases in many chronic health conditions” says Dr. Colditz. “We need to develop and implement ‘outside the box’ interventions in order to have a significant effect on the obesity epidemic.”
The researchers note that population-based strategies are needed to help reduce modifiable risk factors for overweight and obesity. They recommend:
- Developing and implementing physical environment interventions.
- Enhancing primary care efforts to prevent and treat obesity.
- Altering societal norms of behavior.
In 2012, the Institute of Medicine identified population-based and environmental strategies to prevent and combat obesity. Dr. Colditz says that delivering these strategies should be a leading priority to counter the burden of obesity on contemporary and future generations.