Overweight people in their twenties who then become obese later in life could be three times more likely to develop cancer of the esophagus or upper stomach, according to a study published Wednesday in the British Journal of Cancer.

Researchers examined over 400,000 individuals’ reported height and weight at ages 20, 50, and at the time of reporting. Then, the researchers followed up to see which participants developed cancer of the upper stomach or esophagus.

The finding: Participants who reported being overweight at 20 were about 60-80 percent more likely to develop these cancers compared to people who reported staying at a healthy weight.

"This study further highlights the importance of keeping a healthy weight throughout life to reduce the risk of developing these cancers,” Sarah Williams, health information manager at Cancer Research UK, said in a press release

Those who gained more than 45 pounds also faced twice the risk of developing esophageal cancer, compared to those who maintained a healthy weight.

“This study highlights how weight gain over the course of our lives can increase the risk of developing these two cancer types, both of which have extremely poor survival,” Dr. Jessica Petrick, the study’s leader, said.

Why the relation? Excess weight can lead to long-term reflux problems and heartburn that can eventually lead to cancer, according to Petrick. But those aren't the only side effects of carrying extra weight around. “It can also change the levels of sex hormones, such as estrogen and testosterone, cause levels of insulin to rise and lead to inflammation,” Petrick explains, “all of which are factors that have been associated with increased cancer risk."