Study: Americans Becoming Obese Earlier in Life

Americans are becoming obese earlier in life, according to researchers at the University of North Carolina at Chapel Hill.

Twenty-six percent of U.S. men and 28 percent of U.S. women are obese by age 36, according to the study of weight gain among different ethnic groups, races and sexes that appeared in the Annals of Internal Medicine.

The researchers also found that ethnic groups put on weight at different rates.

Although the researchers are not sure why, black women become obese more than twice as fast as white women and Hispanic women become obese 1.5 times as fast as white women. Men also become obese at different rates according to their ethnic group.

"We found Hispanic men became obese 2.5 times faster than U.S. men of European ancestry," said Dr. Kathleen M. McTigue, co-author of the study. "We saw no difference in the rate of obesity development between black and non-Hispanic white men until after age 28 when black men in this country became obese 2.2 times more rapidly than white men."

Researchers analyzed information on 9,179 people born between 1957 and 1964 who were enrolled in the National Longitudinal Survey of Youth beginning in 1979.

More than 80 percent of the participants who were obese by age 36 did not become obese until after ages 20 to 22, although many of them began putting on weight earlier, said McTigue.

"Based on their gender, ethnicity and body mass index at ages 20 to 22, we could fairly accurately predict who would be obese at ages 35 to 37," McTigue reported.

Adult obesity in the United States has doubled in adults between the ages of 20 and 74 during the past 40 years, from 13 percent to 27 percent. Currently, sixty-one percent of U.S. adults are either overweight or obese, said McTigue.

"Obesity is important for health, and, as healthcare professionals, we need to pay more attention to it," advised McTigue. "In the group we studied, there was substantial obesity at ages much younger than most of obesity's health complications tend to occur. Early intervention with such people has the potential to prevent significant illness and should not be overlooked."

McTigue recommends that more emphasis be placed on preventing obesity by focusing more on children and young adults who are only slightly or moderately overweight.

"Since African-American and Hispanic young adults are at particular risk for obesity, we also need to better understand ethnic differences in weight development so that we can design effective interventions," said McTigue.

Other sources: UNC, American College of Physicians-American Society of Internal Medicine