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Most overweight Americans want to lose a few pounds, but only half say they are seriously trying to do so, a new poll suggests.

In the Gallup poll, about one-third of the American adults surveyed said they weighed at least 20 lbs. (9 kilograms) more than their "ideal weight." And among those people, 90 percent said they "would like to lose weight."

But only 48 percent said they were "seriously trying to lose weight."

The poll was conducted last month, and participants were asked to report their actual weight and their ideal weight. For men, the average weight was 196 lbs. (89 kg), and the average ideal weight was 183 lbs. (83 kg). For women, the average weight was 155 lbs. (70 kg), and the average ideal weight was 139 lbs. (63 kg). [The Best Way to Lose Weight Safely]

Gallup has conducted this same poll yearly for the past five years. The results from all five polls include a total of nearly 5,000 people, and show that about 18 percent of U.S. adults are at their ideal weight, while 35 percent of women and 29 percent of men are at least 20 lbs. over their ideal weight.

The combined polls also show that, although most people who are overweight realize they need to lose weight, the percentage of people who are seriously trying to lose weight is not increasing over time, Gallup said.

The findings follow another recent poll from Gallup showing that fewer Americans want to lose weight. In 2015, 49 percent of Americans said they would like to lose weight, down from about 60 percent in 2007. This decrease could reflect an increase in Americans who consider themselves a "healthy weight" even though they are overweight, Gallup said.

At the same time, America's obesity rate is on the rise, increasing from 30.5 percent in 1999-2000 to 37.7 percent in 2013-2014, according to a recent study from the Centers for Disease Control and Prevention.

Extra weight increases people's risk of a number of health conditions, including heart disease, high blood pressure, stroke and type 2 diabetes, and losing weight can reduce the risk of those conditions.

Losing weight, and keeping it off, requires a commitment to lifestyle changes, including eating a healthier diet and increasing exercise. Even a weight loss of 5 percent of a person's body weight can lead to improvements in health, such as lower blood pressure and cholesterol, according to the CDC.

It's important to note that the poll did not use a medical definition of overweight, but instead used participants "ideal weight" as a gauge to whether they were overweight.

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