A recent study pointed out to more than twice the risk of esophageal cancer in overweight teens than those having a normal weight

The researchers were amazed to find that events -- particularly weight and socioeconomic status -- up to the age of 17 years had a tremendous impact upon cancer development later in life. Adolescents who were overweight had a 2.1-fold increased risk of developing esophageal cancer. Adolescents who were of low socioeconomic status had a 2.2-fold increased risk of developing intestinal type gastric cancer. Those who had nine years or less of education had a 1.9-fold increased risk of developing this type of cancer. Also, immigrants born in Asian and former USSR countries had higher risks of developing gastric cancer (3.0-fold and 2.28-fold increased risks, respectively).
"Adolescents who are overweight and obese are prone to esophageal cancer, probably due to reflux that they have throughout their life. Also, a lower socioeconomic position as a child has a lot of impact upon incidence of gastric cancer as an adult," said Dr. Levi. "We look at obesity as dangerous from cardiovascular aspects at ages 40 and over, but here we can see that it has effects much earlier." He noted that it is unclear whether losing weight later in life or gaining higher socioeconomic status might reduce the risks observed in this study.
Source-Eurekalert