Feb. 1, 2011 -- Children who have their tonsils removed tend to gain weight after the surgery, according to an analysis of studies conducted over the past four decades.
Tonsillectomy is one of the most commonly performed surgeries in kids, with more than half a million children in the U.S. having either their tonsils or their tonsils and adenoids removed each year.
While the new research does not prove a direct link between the surgery and weight gain, it does raise questions about whether tonsillectomy may be contributing in some small way to the dramatic rise in childhood obesity, says pediatric ear, nose, and throat specialist Anita Jeyakumar, MD, of Saint Louis University, who led the study.
“Certainly, the obesity epidemic is primarily due to lifestyle,” she says. “But about 30% to 50% of this generation of children are now overweight, and we don’t fully understand the reason for this.”
Tonsillectomy Patients Had Greater Weight
Fewer American children are having their tonsils removed than in past decades, and the reason for having the surgery has also changed, Jeyakumar tells WebMD.
“Forty years ago, the most common indication for tonsillectomy was infection,” she says, adding that today the main indication is sleep disturbance due to breathing difficulties, known medically as "sleep disordered breathing."
The study included nine studies conducted between 1970 and 2009 involving about 800 children up to age 18 who had their tonsils removed, with or without the removal of their adenoids.
Since the studies involved different methods to measure weight gain, the analysis was divided into three sections.
In one, body mass index (BMI) was used as the marker of weight gain in 127 children. Within a year of surgery, the average increase in BMI was around 7% among children who had their tonsils removed.
In another, involving 249 children, 50% to 75% experienced weight gains in the year following surgery.
Across all three analyses, an association between tonsillectomy and greater-than-expected weight gain was seen, regardless of whether children were normal weight or overweight prior to surgery.
The study appears in the February issue of the journal Otolaryngology -- Head and Neck Surgery.
Expert Questions Tonsillectomy, Obesity Link
Pediatric otolaryngologist Julie Wei, MD, says parents should not be overly alarmed by the findings.
Wei is an associate professor at the University of Kansas School of Medicine in Kansas City.
“There is a big difference between association and cause,” Wei tells WebMD. “It is good that these researchers have raised the question, but we certainly can’t say from this study that this surgery contributes to obesity.”
Wei points out that virtually an entire generation of children born prior to World War II had their tonsils removed to prevent rheumatic fever, which often proved fatal before the era of antibiotics.
“That generation certainly did not become obese,” she says.