What role does height play in someone's cancer risk? When it comes to colorectal cancer, new research suggests being taller may indeed increase someone's risk.
"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," said Gerard Mullin, MD, Associate Professor in the Division of Gastroenterology and Hepatology at Johns Hopkins Medicine, who is the corresponding author of the new analysis.
His team conducted a meta-analysis of 47 previous observational studies that had looked at association between adult-attained height and colorectal cancer or adenoma. The cumulative data showed that every 10-centimeter increase (about 4 inches) in height was associated with a 14 percent increased risk of developing colorectal cancer and 6 percent increased odds of having adenomas.
The average height in the U.S. for men is 5 feet, 9 inches, and for women it is 5 feet, 4 inches, according to the Centers for Disease Control and Prevention. So, per this new research, men who are 6 feet, 1 inch, and women who are 5 feet, 8 inches (or 4 inches/10 centimeters above the average U.S. height) or taller are at a 14 percent increased risk of colorectal cancer and a 6 percent increased risk of adenomas.
This data suggests that height is an overlooked risk factor and should be considered when evaluating and recommending patients for colorectal cancer screenings, Mullin explained. The data were published in the journal Cancer Epidemiology, Biomarkers & Prevention earlier this year (2022; https://doi.org/10.1158/1055-9965.EPI-21-0398).
Study Details
The meta-analysis included a total of 280,644 colorectal cancer and 14,139 colorectal adenoma cases. The researchers also included original data from the Johns Hopkins Colon Biofilm study, which recruited 1,459 adult patients undergoing outpatient colonoscopies to explore the relationship between cancer and bacteria stuck to the walls of the colon (biofilm).
The team compared the highest versus the lowest height percentile of various study groups. The research showed that, compared with the lowest percentile, individuals in the highest percentile of height had a 24 percent higher risk for developing colon cancer.
The results were adjusted for demographic, socioeconomic, behavioral, and other known risk factors of colorectal cancer. Those risk factors include so-called non-modifiable factors such as age, a personal or family history of colorectal cancer or adenomas, and a personal history of chronic inflammatory bowel disease.
It's important to point out that the study does not prove causal effect, or that taller stature is as dominant a risk factor as age or genetics. But the data does strengthen the theory that people who are taller may be at increased risk of these types of tumors.
"No one has previously collected this robust and global of a dataset for colorectal neoplasia and colon cancer with attained height," Mullin said.
These data do suggest that height should be a factor in guidelines on who colorectal cancer screening is recommended for, Mullin said. "More studies on attained height and risk will help define colon cancer guidelines."
As to why people who are taller may be more likely to develop colon cancer, there's no conclusive answer.
"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," stated Elinor Zhou, MD, gastroenterologist at The Melissa L. Posner Institute for Digestive Health and Liver Disease at Mercy Medical Center in Baltimore, and co-first author of the study.
It could be that the larger number of cells with more active cellular proliferation are able to mutate, or that somatomedin or growth hormones that increase attained height are driving mutations, Mullin explained.
Zhou noted that more research is needed to better understand how future guidelines could include height as a colon cancer risk factor. "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. "We need more studies before we can definitively say at what height you would need earlier colorectal cancer screening."
Sarah DiGiulio is a contributing writer.
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