Childhood Obesity
Obesity is measured in terms of body mass index (BMI). Since children’s body composition changes with age, BMI is measured against standardized growth charts, which take into account a child’s sex, age and weight. Using these definitions, an overweight child has a BMI above the 85th percentile and lower than the 95th percentile. Obesity is a BMI at or above the 95th percentile.

According to the CDC, overall, about 16 percent of children in the U.S. are obese. The extra weight increases the risk for health problems normally seen in adults, like high blood pressure, high cholesterol and type 2 diabetes. Overweight children are also at higher risk for asthma, sleep apnea and orthopedic/joint problems. The CDC reports hospital costs for obesity-related problems in children and adolescents were approximately $127 million in 1999. Children and adolescents who are obese tend to remain overweight as adults, carrying with them a high risk of adult obesity-related complications.

Aldosterone, Obesity and the Heart
Aldosterone is a hormone produced by the adrenal glands to help the body regulate blood pressure. Researchers at the Medical College of Georgia have discovered obese boys tend to have higher levels of aldosterone, and in turn, enlarged hearts. Hypertension Researcher Gregory Harshfield, Ph.D., says fat cells appear to secrete a substance that causes the adrenal glands to secrete more aldosterone. For an unknown reason, the connection was not seen in obese girls.

While elevated aldosterone levels normally would cause an increase in blood pressure, Harshfield says the boys in the study had normal blood pressure. In addition, family history didn’t seem to have any influence on the findings.

Researchers want to find out why males regulate aldosterone differently from females. In the meantime, Harshfield suggests if parents have an obese son, he should get a blood test to measure aldosterone levels. If those levels are elevated, then the child may need a cardiovascular exam to monitor blood pressure and screen for heart problems. Parents should also place the child on a diet and exercise program to lower his risk for cardiovascular disease.

AUDIENCE INQUIRY
For general information on childhood obesity:
Centers for Disease Control and Prevention, http://www.cdc.gov/obesity

BIBLIOGRAPHY
American Academy of Pediatrics, “Policy Statement: Prevention of Pediatric Overweight and Obesity,” Pediatrics, August 2003, Vol. 112, No. 2, pp. 424-430.

Connell, John, et al., “A Lifetime of Aldosterone Excess,” Endocrine Reviews, April 2008, Vol. 29, No. 2, pp. 133-154.

Reinehr, Thomas, M.D., et al., “Onset of Puberty and Cardiovascular Risk Factors in Untreated Obese Children and Adolescents,” Archives of Pediatrics and Adolescent Medicine, August 2009, Vol. 163, No. 8, pp. 709-715.

Sweeting, Helen, “Gendered Dimensions of Obesity in Childhood and Adolescence,” Nutrition Journal, January 14, 2008, Vol. 7, No. 1.

Wille, Nora, et al., “The Impact of Overweight and Obesity on Health-related Quality of Life in Childhood,” BMC Public Health, December 23, 2008, Vol. 8, No. 421.

Yoshimoto, Takanobu, and Yukio Hirata, “Aldosterone as a Cardiovascular Risk Hormone,” Endocrinology Journal, June 2007, Vol. 54, No. 3, pp. 359-370.