Taller people have a higher risk of colon cancer than shorter folks, and researchers say height should be considered when it comes to screening for the disease.
For the new study, the research team at Johns Hopkins Medicine in Baltimore analyzed data from 47 international studies that included more than 280,000 cases of colorectal cancer and more than 14,000 cases of precancerous colon polyps (adenomas). Data from a Johns Hopkins' study of more than 1,400 adults who had colonoscopies was also included.
"The findings suggest that, overall, the tallest individuals within the highest percentile of height had a 24% higher risk of developing colorectal cancer than the shortest within the lowest percentile," said study co-author Dr. Gerard Mullin, associate professor of gastroenterology and hepatology.
Simply put, every 3.9-inch (10-centimeter) increase in height was associated with a 14% higher risk for colon cancer and 6% higher odds of adenoma, the findings showed.
That means men who are 6 feet 1 inch and women who are 5 feet 8 inches or taller have a 14% increased risk of colon cancer and a 6% increased risk of adenomas, according to the report published online March 1 in Cancer Epidemiology, Biomarkers & Prevention.
In the United States, average heights are 5 feet 9 inches for men and 5 feet 4 inches for women.
"This is the largest study of its kind to date," Mullin said in a Hopkins news release. "It builds on evidence that taller height is an overlooked risk factor, and should be considered when evaluating and recommending patients for colorectal cancer screenings."
Doctors now focus on genetic and age-related risks for recommending colon cancer screenings.
Mullins noted that the findings don't prove cause and effect, or that being taller is as strong a risk factor as age or genetics, but it does reinforce long-noted associations between being taller and colon cancer risk.
The researchers suggested that tallness may be as much of a risk factor for colon cancer as lifestyle factors, such as smoking, drinking and a diet high in processed red meat.
Study co-author Dr. Elinor Zhou said that "one possible reason for this link is that adult height correlates with body organ size. More active proliferation in organs of taller people could increase the possibility of mutations leading to malignant transformation."
Zhou, a gastroenterologist, said more research is needed to identify specific populations of taller people at risk for colon cancer.
"For instance, tall athletes and individuals with inherited tallness, such as those with Marfan syndrome, could be screened earlier and the impact of height further explored," she said.
Colon cancer is the third most common cancer in the United States, according to the American Cancer Society.
There's more on colorectal cancer screening at the U.S. National Cancer Institute.
SOURCE: Johns Hopkins Medicine, news release, March 3, 2022