Excess Weight Is to Blame for 4 Percent of Cancers Globally

An important new report cautions that excess weight appears to be linked to roughly 4 percent of cancers around the world. Assessed for the year 2012, the study looked at cancer in relation to body weight for both overweight and obese patients. Of course, this study is alarming because, even though the relationship between weight and cancer was only very small in this case, the rate is likely to continue to rise over the next few decades.

Conducted by scientists from Harvard University and Imperial College London, the study suggests that excess body weight is not just a risk factor for cancer but could be directly responsible for more than 544,000 cancers around the world, every year.

Indeed, excess body weight is a measure that has been steadily increasing globally since the 1970s.  In that decade, data tells us no more than 7 percent of the entire American population was obese; another 13 percent were overweight. Within the next two decades (the 1990s), the obesity rate had doubled.  And then, last year it was assessed that approximately 40 percent of adults and 18 percent of children (between the ages of 5 and 19), around the world, had excess body weight.   The numbers are worse in the United States, where nearly two-thirds of all adults are either overweight or obese.

And this translates to similar variation in terms of cancer.  For example, obesity accounts for roughly 7 percent of cancers in the United States, a country with relatively high wealth but low physical activity.  But obesity only accounts for less than one percent of cancers in poor countries like India and Ethiopia.

That said, some of the biggest jumps in this metric have been found in low- and middle-income countries.  Analysts argue that the spread of the “Western” lifestyle is the likely culprit.  The “Western” lifestyle includes a diet of fatty and sugary foods that have low nutrition coupled with low physical activity levels.

While this knowledge is becoming more and more concrete, we still do not have a grasp on the direct link between obesity and cancer. For now, the accepted dominant theory suggests that people who are overweight simply have more insulin in their bodies and this insulin growth factor could encourage cancer development. Another theory suggests that obesity-related inflammation in the body might actually be carcinogenic, itself.