October 4, 2023 – Forty-five minutes of vigorous exercise 3 times per week may reduce the chance of cancer in patients with Lynch syndrome, a genetic disorder that may result in cancer at a young age.
The Amount of exercise Researchers on the University of Texas MD Anderson Cancer Center have found that the immune system is best in a position to eradicate cancer cells. The intervention — 45 minutes of high-intensity cycling three days per week — was specific in nature, said oncologist Eduardo Vilar-Sanchez, MD, PhD, professor of clinical cancer prevention and lead creator of the study.
“We wanted to make the recommendation very specific,” he said. “People don’t follow vague lifestyle advice like ‘just exercise.’ We wanted to link a specific biological effect to a very specific intervention.”
The study was small (just 21 people), nevertheless it is predicated on a wealth of evidence linking regular exercise to a reduced risk of cancer, particularly colorectal cancer. But MD Anderson researchers went a step further and investigated How Exercise could reduce the chance of cancer.
Exercise and the immune system
All 21 people within the study had Lynch syndrome and were divided into two groups. One received a 12-month training program; the opposite doesn't. The scientists checked their cardio and respiratory fitness and tracked immune cells – natural killer cells and CD8+ T cells – within the blood and colon tissue.
“These are the immune cells that are responsible for attacking foreign entities like cancer cells,” Vilar-Sanchez said, “and they were more active in the participants who exercised.”
Participants within the exercise group also noticed a decrease within the inflammatory marker prostaglandin E2 (PGE2). The decline was closely related to the rise in immune cells. Both changes indicate a stronger immune response.
The researchers consider that the changes are related to a rise within the body's “immune surveillance system” in looking for and eliminating harmful cells otherwise become cancerous.
Building on previous research results
Science already provides ample evidence that regular exercise may also help prevent cancer. An enormous one Systematic review 2019 More than 45 studies and several other million people found strong evidence that exercise can reduce the chance of assorted kinds of cancer – including bladder, breast, colon and stomach cancer – by as much as 20%.
However, the MD Anderson study is the primary to point out a link between exercise and changes in immune biomarkers, the researchers said. “It's one thing to know the epidemiological context, but it's another thing to know the biological basis,” says Xavier Llor, MD, PhD, director of the GI Cancer Prevention Program at Yale Cancer Center and professor of drugs at Yale School of Medicine. (Llor was not involved within the study.)
Two previous studies examined exercise and inflammatory markers in healthy people and in individuals with a history of colon polyps, but neither study produced meaningful results. The success of this latest study may very well be resulting from more intense training or additional colon tissue samples. But advances in technology now allow for more sensitive measurements, the researchers said.
What it is best to know
Vilar-Sanchez was hesitant to increase the study results beyond individuals with Lynch syndrome, but is optimistic that they might be applicable to the overall population.
Llor agrees: “Through some of these mechanisms, exercise could protect against other cancers,” he said.
According to the American Cancer Society, greater than 15% of all cancer deaths (excluding tobacco-related cancers) within the United States are resulting from lifestyle aspects, including physical inactivity, obesity, alcohol consumption and poor eating regimen. It recommends 150 to 300 minutes moderately intense exercise per week to scale back the chance of cancer. Study participants saw a big immune response with 135 minutes of high-intensity exercise per week.
“The public should know that participation in any form of exercise results in this somehow lead to implications for cancer prevention,” said Vilar-Sanchez.