We know that diet and antibiotic use has a direct and immediate affect on our gut microbiome – the giant colony of healthy and unhealthy bacteria that resides in our intestinal tract. But, what about exercise?
Two recent studies, one involving mice and one involving humans, showed that exercise also impacts our microbiome in extremely important ways.(1,2) One, in particular, leads to a reduced risk of colon cancer and other painful, intestinal conditions such as colitis or ulcerative colitis.
How Exercise Prevents Colon Cancer
The studies revealed that exercising three times per week, for 30 to 60 minutes promotes an increase of numerous, beneficial short-chain fatty acids (SCFAs), including one called butyrate.
Scientists were surprised to find that, even when injected with chemicals to trigger colitis symptoms and inflammation in the colon, the short-chain fatty acids quashed inflammation and regenerated molecules in test subjects.
Butyrate are beneficial SCFAs with anti-inflammatory properties. They are directly involved in the prevention of colon cancer as well as a host of other painful, gut-related medical conditions.(3) This is due to the epigenetic effects of butyrate which inhibit the growth and metastasis of cancer cells and cause apoptosis – the spontaneous death of cancer cells.(4)
Although butyrate is most commonly generated through the intake of dietary fiber, these studies demonstrate that, irrespective of diet, exercise provides some of the same benefit.
Diet Still More Beneficial Than Exercise
Researchers noted a couple of interesting findings: SCFA levels decreased after study participants returned to a sedentary lifestyle for six consecutive weeks following the study exercise program, which highlights the importance of ongoing exercise throughout life.
In addition, a distinct difference in SCFA levels was observed between obese participants and that of lean study participants. Although SCFA levels increased in lean study participants, there was no change in the gut microbiota of obese test subjects. This made clear the necessity for overweight individuals to first use a high-fiber, plant-based diet and other means to achieve weight-loss and increase butyrate levels in order reap the highest rewards from exercise and prevent disease.
- Allen, J. M., L. J. Mailing, J. Cohrs, C. Salmonson, J. D. Fryer, V. Nehra, V. L. Hale, P. Kashyap, B. A. White, and J. A. Woods. “Exercise training-induced modification of the gut microbiota persists after microbiota colonization and attenuates the response to chemically-induced colitis in gnotobiotic mice.” Gut Microbes, September 1, 2017, 1-16. doi:10.1080/19490976.2017.1372077.
- Allen, Jacob M., Lucy J. Mailing, Grace M. Niemiro, Rachel Moore, Mark D. Cook, Bryan A. White, Hannah D. Holscher, and Jeffrey A. Woods. “Exercise Alters Gut Microbiota Composition and Function in Lean and Obese Humans.” Medicine & Science in Sports & Exercise, November 20, 2017, 1. doi:10.1249/mss.0000000000001495.
- Zeng, Huawei. “Mechanisms linking dietary fiber, gut microbiota and colon cancer prevention.” World Journal of Gastrointestinal Oncology 6, no. 2 (February 15, 2014): 41. doi:10.4251/wjgo.v6.i2.41.
- Canani, Roberto Berni. “Potential beneficial effects of butyrate in intestinal and extraintestinal diseases.” World Journal of Gastroenterology 17, no. 12 (March 28, 2011): 1519. doi:10.3748/wjg.v17.i12.1519.