New Study Estimates That 4 Percent Of Cancers Worldwide Are Caused By Obesity


A new global study has estimated that being obese or overweight causes 4 percent of cancers worldwide.

Conducted by researchers at Harvard University and Imperial College London, the study suggested that excess body weight is not only a risk factor, but is also responsible for 544,300 cancers a year worldwide.

Per a report by the Daily Mail, two-thirds of Americans and more than 2 billion people across the globe are obese or overweight, and according to experts, the numbers are expected to rise in the coming decades.

The report also detailed that poor diets not only add to the risks associated with obesity itself but also contribute to seven of the 10 leading causes of death in the United States.

Rates, however, significantly vary across the globe. Per the report, in the US, obesity is the cause of nearly 7 percent of cancers where citizens are wealthy but not physically active. In comparison, poorer nations like India and Ethiopia have less than 1 percent of cancers that can be attributed to obesity.

The authors of the study have urged policymakers to develop strategies that could reverse the upward trend of obesity and the cancers that are caused because of it.

The Daily Mail report also revealed that in the US and other Western countries, obesity has reached epidemic proportions. Although it is almost impossible to identify a clear start for the epidemic, statistics have shown that since the 1970s, people’s Body Mass Indexes (BMIs) and waistlines have been growing in the US. At the time, only about 7 percent of the American population was obese and 13 percent was overweight.

By the 1990s, however, rates of obesity doubled to 15 percent, and in the next two decades, the problem escalated. At present, one in three adults in the United States is obese.

Although it’s been quite clear why being obese or overweight can increase the risk of heart diseases and diabetes, a link between excess body weight and cancers remains unclear.

Dominant theories suggest that higher levels of insulin in obese people’s blood may encourage the growth of cancers, or that inflammation related to obesity itself could be carcinogenic.

The report said that the development of breast and endometrial cancers in women may be attributed to higher levels of estrogen in overweight women.

According to previous studies, being overweight or obese can increase the risks of developing 13 specific kinds of cancers and recent research has also shown that obesity can likely cause prostate, oral, and esophageal cancers.