Childhood Obesity Raises Risk of Certain Cancers
When one thinks of the risks associated with childhood obesity, often the first thoughts are of heart disease, high blood pressure, and diabetes. But a new study from Tel Aviv University warns parents of another danger they should consider: a significantly higher risk of certain cancers that can develop when their children grow up.
Obesity now could mean cancer later
Among American children ages 2 to 19 years, the rate of overweight or obesity ranges from nearly 30% to more than 40%, depending on the population. For example:
- For non-Hispanic blacks, the rates are 30.8% of males and 39.2% of females
- For non-Hispanic whites, 31.9% of males and 29.5% of females
- For Mexican Americans, 40.8% of males and 35.0% of females
According to new research from investigators at Tel Aviv University, overweight and obese young people, defined as a body mass index (BMI) in the 85th percentile and greater, have a 50% higher risk of developing urothelial (urinary tract and bladder) or colorectal cancers in adulthood compared with their peers who have a lower BMI.
To arrive at these findings, the researchers evaluated data from 1.1 million males in the Israeli Defense Forces, with a follow-up period of 18 years. Although a connection was made between childhood obesity and colorectal and urothelial cancers, the investigators believe further research will uncover connections with other types of cancer as well.
Other studies of childhood obesity and cancer
In a study published in the May 2012 issue of the Journal of Pediatrics, researchers at Tufts University School of Medicine found that for women, those who were overweight in childhood have an increased risk of all-cause and breast cancer death.
A study appearing in the June 2012 issue of the Annals of Oncology noted an association between obesity at a young age with subsequent risk of esophageal squamous cell carcinoma. The researchers reported that a very obese size at age 15 among females, but not among males, was associated with a higher risk of esophageal squamous cell carcinoma.
In a 2011 study published in Cancer Prevention Research, investigators explored body fatness during early life to the risk of colorectal cancer or adenoma (benign tumor) in women. They found that "higher height and body fatness during childhood was associated with increased risk of distal adenoma later in life."
Importance of the new study
Dr. Ari Shamiss, of Tel Aviv University's Sackler Faculty of Medicine and one of the study's co-authors, noted that in addition to conducting further research on the link between childhood obesity and cancer risk, it's important to know whether weight loss could reduce a child's risk of developing urothelial or colorectal cancer as an adult.
The Tel Aviv University study did not address the weight loss question. However, given what is already known about the health risks associated with childhood obesity, the additional finding of certain cancer risk makes the need for weight control even more important.
Etemadi A et al. Large body size and sedentary lifestyle during childhood and early adulthood and esophageal squamous cell carcinoma in a high-risk population. Annals of Oncology 2012 Jun; 23(6): 1593-600
Must A et al. Occurrence and timing of childhood overweight and mortality: findings from the Third Harvard Growth Study. Journal of Pediatrics 2012 May; 160(5): 743-50
Nimptsch K et al. Body fatness during childhood and adolescence, adult height, and risk of colorectal adenoma in women. Cancer Prevention Research (Philadelphia) 2011 Oct; 4(10): 1710-18
Tel Aviv University