Research has established that overweight men - particularly those who gain weight during adulthood, and surprisingly even those who are not clinically overweight based on their BMI (Body Mass Index) - are in the ‘high risk’ zone when it comes to colon cancer.

To confirm the fact that weight gain increased colon cancer risk, researchers conducted a study on men in the age-group of 40 - 75 years, none of whom had been diagnosed with cancer or ulcerative colitis. All the 46,349 men were asked questions about their lifestyle, diet, weight and medical history. Every couple of years or so, this data was updated.

On the basis of this study, of all colon cancers diagnosed over a period of 18 years, almost one-third were associated with a BMI greater than 22. Specifically speaking, it was found that men with an average BMI between 20 and 22 had a lesser risk of cancer, in comparison to men with BMI above 22. Furthermore, in the case of obese men, with BMI over 30, the risk of colon cancer doubled
 
As per the research, for a weight gain of 10 pounds, during the slated time period, the risk of colon cancer increased by 14%. This risk increased by 33%, if one gained 5 kg every 10 years after the age of 21. However, the risk factor is near negligible at 21 years, almost irrespective of the weight. Hence, for the timely prevention of colon cancer, public health interventions to avoid weight gain require widespread support.