Fat Levels Higher in Thin Children” width=”290″ height=”249″ />A study conducted by Children’s Hospital Boston and the Joslin Diabetes Center has revealed that levels of “brown fat,” a healthy type of fat that appears in children, increase in puberty and then decrease after. The study also showed that thinner children have higher levels of brown fat. The study was published in the Journal of Pediatrics.
Researchers used PET scans to reveal the locations and concentrations of brown fat in children. Brown fat is unlike white fat in that it actually contributes to the burn-off of energy instead of functioning as an energy storage mechanism.
The study has important implications for fighting diabetes in children. “Increasing the amount of brown fat in children may be an effective approach at combating the ever increasing rate of obesity and diabetes in children,” said Aaron Cypess, MD, PhD. Cypess was the senior author of the paper in addition to being assistant investigator and staff physician at the Joslin Diabetes Center.
This is not Cypress’ first time investigating the role of brown fat in metabolism. His team showed in a 2009 study published in the New England Journal of Medicine that brown fat plays a role in the metabolism of adults as well. Prior to this study, it was accepted that brown fat appeared only in children and babies, but the study proved that brown fat is also found in between 3 and 7.5 percent of adults. Women have a greater chance of storing brown fat.
Cypess’ newest study involved PET scans of 127 children from ages 5 to 21. The researchers found active brown fat in 44 percent of the children; the incidence of brown fat was about the same for boys and girls. Children in the 13 to 15 year old range were most likely to have active brown fat stores, and theirs were the most active. The study also showed that BMI seemed to have an effect on the activity of brown fat: the heaviest children showed the least amount of brown fat activity.
Cypess’ previous study of brown fat in adults showed that brown fat stores were more active in the winter since it had to burn more energy to maintain homeostasis, or the “stabilization” of body temperature. The study of brown fat in children, however, showed that their brown fat stores were active at the same rate throughout the year. The authors of the study said that the decrease in brown fat activity from childhood to adulthood shows that it plays a role in the metabolism of children in addition to weight maintenance and energy balance.
“We believe that the ability to non-invasively evaluate brown fat activity in vivo with PET imaging provides a better understanding of its prominent role in pediatric physiology, and may possibly provide insights into the treatment of childhood obesity,” said Laura Drubach, MD, first author of the study and physician at the Children’s Hospital program in Nuclear Medicine and Molecular Imaging.
Cypess said that treating childhood obesity through this new knowledge would likely involve attempting to increase the activity of brown fat through non-pharmacological methods, such as by lowering the temperature in households or through the intake of certain foods. If those methods were not successful, medication may be necessary.
The Joslin Diabetes Center conducted a study in 2010 which showed that certain mice cells could be turned into brown fat cells. Cypess has hope that the studies will provide new answers in treating childhood obesity: “We might be able to combat the obesity and diabetes epidemics if we find safe ways of increasing brown fat activity. This might be an additional tool in the fight.”
