A researcher at Cedars-Sinai Medical Center in Los Angeles has hypothesized that bodily intolerance to gravity may cause irritable bowel syndrome.
"Our body systems are constantly pulled downward," Brennan Spiegel, MD, director of health services research at Cedars-Sinai and author of the hypothesis published in The American Journal of Gastroenterology, said in a Dec. 1 news release. "If these systems cannot manage the drag of gravity, then it can cause issues like pain, cramping, lightheadedness, sweating, rapid heartbeat and back issues — all symptoms seen with IBS. It can even contribute to bacterial overgrowth in the gut, a problem also linked to IBS."
No underlying cause for IBS has been identified since it was first discovered over 100 years ago. It affects 10 percent of the population, according to the news release.
Other prominent IBS theories include motility abnormalities, hypersensitive gut, abnormal serotonin levels and an irregular autonomic nervous system.
"There's such a variety of explanations that I wondered if they could all be simultaneously true," Dr. Spiegel said in the release. "As I thought about each theory, from those involving motility, to bacteria, to the neuropsychology of IBS, I realized they might all point back to gravity as a unifying factor. It seemed pretty strange at first, no doubt, but as I developed the idea and ran it by colleagues, it started to make sense."
Dr. Spiegel saw a connection between gravity's effect on spinal compression, consequential lack of flexibility and downward organ shift. This can cause IBS symptoms, according to Dr. Spiegel.
"Our nervous system also evolved in a world of gravity, and that might explain why many people feel abdominal 'butterflies' when anxious," Dr. Spiegel continued in the release. "It's curious that these 'gut feelings' also occur when falling toward Earth, like when dropping on a roller coaster or in a turbulent airplane. The nerves in the gut are like an ancient G-force detector that warns us when we're experiencing — or about to experience — a dangerous fall. It's just a hypothesis, but people with IBS might be prone to over-predicting G-force threats that never occur."
The hypothesis still needs to undergo trials and testing. Shelly Lu, MD, the Women's Guild Chair in Gastroenterology and director of the division of digestive and liver diseases at Cedars-Sinai, affirmed in the release that the theory is testable.