Some Americans are losing weight, resulting in more people of normal weight, according to a new survey, but it is not clear if the trend will last.
Researchers for the Gallup-Healthways Well-Being Index found that for the first time in three years there are more normal-weight Americans than those in the overweight category.
But obese and overweight Americans combined make up more than 60% of the population, according to the study, meaning the majority of Americans are at an unhealthy weight.
"Although the majority of Americans are still overweight or obese, it is an encouraging sign that obesity rates are trending downward in the US," the report said.
Obesity a major problem
The researchers conducted telephone interviews with a random sample of 90,070 people aged 18 and older from July to September.
Based on the responses, they calculated that 36.6% of Americans are normal weight, while the number of overweight people came in at 35.8%. Obese Americans make up 25.8% of the population.
The study used survey answers to determine individuals' body mass index, a measure of weight relative to height. A score of 30 or higher is classified as obese, while 25.0 to 29.9 is overweight. A BMI between 24.9 and 18.5 is classified as normal weight and below 18.5 is considered underweight.
Obesity has become a major problem in the US over the last decade.
In 2000, no US state had an adult obesity rate higher than 30%, according to Centres for Disease Control data. In 2010, there were 12 states at that level, and another eight poised to join them with adult obesity rates of 28% or higher.
The study said it was not clear what caused the drop in overweight and obese Americans, but said it could be due to the tough economy, with cash-strapped Americans choosing to eat in rather than eating high-Kilojoule restaurant meals.
Another reason could be increased public awareness efforts, such as Michelle Obama's Let's Move! anti-obesity campaign, and business initiatives that prompted more health-conscious decisions.
A downward trend in obesity rates could also mean a drop in US health care costs, the study said. The Centres for Disease Control and Prevention estimated medical costs associated with obesity were $147 billion in 2008.
(Reuters Health, October 2011)