Does melatonin cause constipation
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Does Melatonin Cause Constipation?
Introduction to Melatonin and Gut Health
Melatonin, a hormone primarily known for regulating sleep-wake cycles, also plays a significant role in gastrointestinal function. It is produced in large quantities in the gastrointestinal tract and has been studied for its effects on gut motility and symptoms of irritable bowel syndrome (IBS) . This article explores whether melatonin can cause constipation, drawing on recent research findings.
Melatonin and Constipation in IBS Patients
Effects on IBS with Constipation (IBS-C)
Research indicates that melatonin can have beneficial effects on patients with IBS, particularly those with constipation-predominant IBS (IBS-C). A study involving postmenopausal women with IBS-C showed that melatonin treatment significantly reduced the intensity of visceral pain and abdominal bloating in 70% of patients and alleviated constipation in 50% of patients over six months . This suggests that melatonin may help relieve constipation rather than cause it in IBS-C patients.
Urinary Melatonin Metabolite Levels
Another study measured the urinary excretion of 6-sulphatoxymelatonin, a primary melatonin metabolite, in IBS patients. It found that melatonin levels were lower in both constipation-predominant and diarrhea-predominant IBS patients compared to healthy controls . This lower melatonin level in IBS patients suggests a potential link between melatonin deficiency and IBS symptoms, including constipation.
Age-Related Changes in Melatonin and Colonic Motility
Decreased Melatonin Release with Age
Age-related changes in melatonin release have been observed in the murine distal colon. As animals age, both basal and mechanically stimulated melatonin release decrease, leading to reduced colonic motility . This decline in melatonin release may contribute to age-related constipation, indicating that melatonin supplementation could potentially improve colonic motility in older individuals.
Exogenous Melatonin and Colonic Transit Time
A study on the effects of exogenous melatonin on colonic transit time (CTT) in healthy subjects and IBS patients found that melatonin treatment increased CTT in healthy controls but did not significantly change CTT in IBS patients . This suggests that while melatonin may slow colonic transit in healthy individuals, it does not exacerbate constipation in IBS patients.
Conclusion
Current research does not support the notion that melatonin causes constipation. Instead, melatonin appears to have a beneficial effect on gut motility, particularly in individuals with IBS-C and age-related constipation. Melatonin supplementation may help alleviate constipation symptoms rather than cause them, making it a potential therapeutic option for improving bowel motility in specific populations.
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