Irritable Bowel Syndrome: The Effects of Gravity

Gravity is a universal force that affects our bodies from the day we are born until the day we die. Because it is ubiquitous and constant, it is often taken for granted. We rarely stop to think about how gravity affects our bodies. However, recent research shows that this powerful force can have a significant impact on both general well-being and gut health in particular. 

Dr. Brennan Spiegel and his colleagues at Cedars Sinai recently emerged with a new hypothesis indicating that IBS and gravity may be related. If supported by further evidence, this hypothesis has the potential to completely change our understanding of this disease, which has been puzzling researchers for years. 

What is IBS?

IBS, or irritable bowel syndrome, is a chronic gastrointestinal disease that can cause recurrent abdominal pain, changes in consistency of stool, and changes in frequency of bowel movements. It is among the most common GI conditions, affecting 10% of the global population and 15% of the United States population. In addition, it is more prevalent in women than men. According to Johns Hopkins Medicine, IBS affects twice as many women as men in Western countries.

IBS is often debilitating and significantly affects quality of life. It is categorized into 4 subtypes based on its predominant symptoms. These are:

1. IBS-C, which has main symptoms of abdominal pain and constipation
2. IBS-D, which has predominant diarrhea and abdominal pain
3. IBS-mixed, which has both loose stools and constipation, along with abdominal discomfort
4. IBS-U, which has highly variable symptoms

Each of these subcategories is about equal in prevalence. 

Besides diarrhea, constipation, and abdominal pain, other IBS symptoms include:

• Mucus in stool
• Increased urgency of bowel movements
• A feeling that defecation has not completely cleared stool from the rectum

The gut and the brain have shown to be intrinsically connected, and IBS is thought to be a problem with this gut-brain connection. This is based on evidence of association between IBS and psychological conditions, such as anxiety and depression. Treatment of the psychological conditions seems to help IBS as well, which also suggests an association between the two. Beyond this, our understanding of IBS is incomplete. There are a variety of current, evidence-based hypotheses that have attempted to explain the etiology of this disease, but none of them are all-encompassing. 

Gravity and IBS

Current Hypotheses on IBS:

Besides the neuropsychological theory, there is also a predominant hypothesis that IBS has to do with the gut microbiome, as it has been responsive to treatments that increase microbiome diversity and balance. A third hypothesis proposes that IBS could have to do with impairment of proper motility. Another hypothesis indicates that dysregulation of the neurotransmitter serotonin may be the cause of maladies associated with IBS. The fact that there are so many evidence-based hypotheses seems to beg the question, is there a connection between any of these characteristics of IBS?

Dr. Spiegel set out to answer this very question in an interesting way. He considered the possibility that all of these hypotheses could be true simultaneously. His thinking led him to the proposition that gravity may be the connecting factor between all of the seemingly conflicting causes of IBS. It seemed like a strange idea at first, but it became clearer and more logical as he discussed it with his colleagues. 

The Effect of Gravity:

Since gravity acts on each and every one of us, you may be asking, how does gravity affect individuals with IBS differently than those without it? According to the gravity hypothesis,  this is due to individual variations in how we handle the G-force load on our abdominal organs. Gravity pulls these organs downward constantly, and in most individuals, they are maintained in their proper position. 

However, others may have anatomical variation that changes the disposition of their organs within their abdomen. For example, someone with spinal issues may have a sagging diaphragm and a more protruding abdomen. The skeleton is thought of as the support system for our organs, which helps them deal with the constant force of gravity. Because of this, when musculoskeletal disorders are present, the support system fails, predisposing the viscera to problems such as abdominal compression. 

Dr. Spiegel proposes that this dysregulation of G-force load bearing can cause the other pathogenic processes associated with IBS, including bacterial overgrowth and motility problems. He also connects the nervous system to gravity, explaining why changes in gravity, such as a large drop in a roller coaster, can cause the sensation of “butterflies” in the stomach. Dysregulation of the neurotransmitter serotonin has been found to have an impact on IBS. According to the gravity hypothesis, serotonin regulation issues can cause IBS by impairing one’s ability to pump digestion products through the intestines against the force of gravity. This leads to abdominal discomfort and digestive problems, which are common IBS symptoms.

Summary and Conclusion

It seems that gravity could be the connecting factor between the neuropsychological, gut microbiome, motility, and serotonin hypotheses of IBS pathogenesis. According to Dr. Brennan Spiegel in his new gravity hypothesis, the way we individually bear the force of gravity due to anatomical variations and musculoskeletal conditions can impact our gut microbiome, motility, and nervous system, leading to the debilitating symptoms of IBS. 

Although Dr. Spiegel’s hypothesis has not yet been tested, it is testable, and he makes several suggestions for research to test this proposal in his article in the American Journal of Gastroenterology. If this hypothesis is supported by further evidence, it has the potential to be widely accepted. According to Dr. Shelly Lu, one of Dr. Spiegel’s colleagues at Cedar Sinai, this hypothesis could change the way we think about IBS and potentially how we treat it as well.