Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


Obesity rates decline for many adolescents but disparities worsen

Obesity rates have started to decline and level off for many adolescents, but continue to increase for certain racial and ethnic minorities, according to a new UCSF-led study.

The evidence of increasing racial disparities for obesity underscores the need for more tailored intervention programs and policies that target high-risk groups, the authors conclude.

The study, which is the first to find significant differences in obesity trends over time by race and ethnicity, appears online in the journal Pediatrics, available at It also will be published in the September 2010 print issue of the journal.

"While the decline and stabilization of obesity among certain groups is encouraging, we are seeing an increase in disparities that is troubling, especially among the most severely obese youth," said first author Kristine Madsen, MD, MPH, an assistant professor of pediatrics at UCSF. "As our country becomes increasingly diverse, it is critical that we act quickly to address these disparities."

Madsen and her co-authors examined trends in the prevalence of high body mass index (BMI) among Hispanic, non-Hispanic white, Asian, black, and American Indian adolescents in California from 2001 through 2008. BMI is a measure of body fat based on a person's height and weight that is commonly used to screen for obesity. Generally, children are considered obese if they have a BMI at or above the 95th percentile, and severely obese if their BMI score is at or above the 99th percentile.

The data revealed that obesity rates at the 95th percentile declined or stabilized among a number of groups during the time period studied. Among white and Asian girls and boys, obesity rates peaked in 2005, then declined over the next three years, with 2008 rates coming in at 12 percent for white youth and 13 percent for Asians. Overall rates for Hispanic youth also peaked in 2005 and then leveled off at 26 percent through 2008; although Hispanic boys did show a small decline on their own. Rates among black boys stayed at the same level each year.

However, from 2001 through 2008, the prevalence of obesity continued to climb for black and American Indian girls, reaching 22 percent and 23 percent, respectively. Furthermore, these two groups were more than three times as likely as white girls to be severely obese, with a BMI at the 99th percentile.

When comparing groups at the 99th BMI percentile, the researchers found that only Asian youth and white boys showed any signs of decline after 2005. All other groups – including Hispanic boys and girls, white girls, black boys and girls, and American Indian boys and girls – peaked in 2005 and then remained at a plateau through 2008.

"When you look at the very heaviest end of the spectrum, the picture is pretty bleak, and we do not yet know if severe obesity rates for these groups will remain at a plateau or continue to increase," Madsen added.

The researchers analyzed the health records of more than eight million fifth-, seventh-, and ninth-grade students in California who underwent the state's mandatory school-based BMI screening. Among the students studied, 46.4 percent were Hispanic, 32.8 percent were white, 12.6 percent were Asian, 7.7 percent were black, and 0.5 percent were American Indian.

According to the researchers, the study's large and highly diverse group of subjects is a unique strength. And, although the data were confined to one state, the results show population level trends that are applicable elsewhere, since about one in eight children in the United States currently live in California.

"We need to focus on implementing real change in the places where kids spend most of their time – at home, at school and in the after-school arena – to encourage healthier habits and reduce consumption," Madsen said. "Priorities must be reconsidered so that health is not an afterthought."

Co- authors on the paper include Patricia Crawford, DrPH, RD, of the Dr. Robert C. and Veronica Atkins Center for Weight and Health at University of California, Berkeley; and Ashley Weedn, MD, of the Department of Pediatrics at University of Oklahoma.

The research was supported by grants from the Robert Wood Johnson Foundation, the Eunice Kennedy Shriver National Institute of Child Health and Human Development, and the American Heart Association.

UCSF Benioff Children's Hospital creates an environment where children and their families find compassionate care at the forefront of scientific discovery, with more than 150 experts in 50 medical specialties serving patients throughout Northern California and beyond. The hospital admits about 5,000 children each year, including 2,000 babies born in the hospital. For more information, visit

UCSF is a leading university dedicated to promoting health worldwide through advanced biomedical research, graduate-level education in the life sciences and health professions, and excellence in patient care. For further information, please visit

Follow UCSF on Twitter at

Kate Vidinsky | EurekAlert!
Further information:

More articles from Studies and Analyses:

nachricht Diagnoses: When Are Several Opinions Better Than One?
19.07.2016 | Max-Planck-Institut für Bildungsforschung

nachricht High in calories and low in nutrients when adolescents share pictures of food online
07.04.2016 | University of Gothenburg

All articles from Studies and Analyses >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: New 3-D wiring technique brings scalable quantum computers closer to reality

Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.

"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...

Im Focus: Scientists develop a semiconductor nanocomposite material that moves in response to light

In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.

A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...

Im Focus: Diamonds aren't forever: Sandia, Harvard team create first quantum computer bridge

By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.

"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...

Im Focus: New Products - Highlights of COMPAMED 2016

COMPAMED has become the leading international marketplace for suppliers of medical manufacturing. The trade fair, which takes place every November and is co-located to MEDICA in Dusseldorf, has been steadily growing over the past years and shows that medical technology remains a rapidly growing market.

In 2016, the joint pavilion by the IVAM Microtechnology Network, the Product Market “High-tech for Medical Devices”, will be located in Hall 8a again and will...

Im Focus: Ultra-thin ferroelectric material for next-generation electronics

'Ferroelectric' materials can switch between different states of electrical polarization in response to an external electric field. This flexibility means they show promise for many applications, for example in electronic devices and computer memory. Current ferroelectric materials are highly valued for their thermal and chemical stability and rapid electro-mechanical responses, but creating a material that is scalable down to the tiny sizes needed for technologies like silicon-based semiconductors (Si-based CMOS) has proven challenging.

Now, Hiroshi Funakubo and co-workers at the Tokyo Institute of Technology, in collaboration with researchers across Japan, have conducted experiments to...

All Focus news of the innovation-report >>>



Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

Agricultural Trade Developments and Potentials in Central Asia and the South Caucasus

14.10.2016 | Event News

World Health Summit – Day Three: A Call to Action

12.10.2016 | Event News

Latest News

New method increases energy density in lithium batteries

24.10.2016 | Power and Electrical Engineering

International team discovers novel Alzheimer's disease risk gene among Icelanders

24.10.2016 | Life Sciences

New bacteria groups, and stunning diversity, discovered underground

24.10.2016 | Life Sciences

More VideoLinks >>>