CHICAGO — The need for the fitness industry to reach out to children in low-income families is becoming even greater as a new study shows an increase in obesity in that population.

The prevalence of being overweight increased from 1989 to 2000 in children aged two to four years from low-income families, according to an article in the December issue of the “Archives of Pediatrics & Adolescent Medicine,” one of the JAMA/Archives journals.

Children who are overweight are at risk for diabetes, gallstones, sleep apnea and high blood pressure, the article states. As adults, they are also at an increased risk for coronary heart disease and atherosclerosis (hardening of the arteries) compared with those not overweight as adolescents.

Researchers from the National Center for Chronic Disease Prevention and Health Promotion, CDC, Atlanta, examined the change in the prevalence of overweight and underweight in children ages two to four years from low income families participating in federally funded programs. The overall trend in the study showed an increased prevalence of overweight in all sex, age and race/ethnicity groups between 1989 and 2000. Of the 30 states included in the study, 28 had an overweight prevalence of more than 10 percent, compared to 11 states in 1989. Also in 2000, three states had overweight prevalences of more than 15 to 20 percent while two had prevalences of more than 20 percent. During the study period, underweight decreased with nine states in 1989 and 23 states in 2000 reporting a prevalence of five percent or less. The researchers did not find a geographic concentration in overweight prevalence.

“In addition, national data representative of the U.S. population also showed increases in overweight prevalence over time, indicating that overweight is a national problem, not a problem exclusively associated with publicly funded programs or low income,” wrote the researchers, who called for expansion of prevention and intervention efforts.