Study under review: The impact of peppermint oil on the irritable bowel syndrome: a meta-analysis of the pooled clinical data
Irritable bowel syndrome (IBS) is a chronic gastrointestinal disorder characterized by recurrent abdominal pain and altered bowel habits (constipation and/or diarrhea), with either predominant symptoms of diarrhea (IBS-D), constipation (IBS-C), both (IBS-M, where the ‘M’ stands for ‘mixed’), or undetermined (IBS-U) as shown in Figure 1. It is the most common functional gastrointestinal disorder, with approximately one out of ten people worldwide suffering from it. Although abdominal pain is one of the most common symptoms, people with IBS may also experience bloating, a sensation of incomplete evacuation, urgency, diarrhea, straining, and constipation. These symptoms can have a significant socioeconomic impact in terms of health care utilization, reduced quality of life, work absenteeism, and reduced work productivity.
Due to the complexity of IBS’ pathology, no single specific cause has been identified. Instead, a combination of several factors have been proposed to contribute to it, including stress, psychosocial factors, alterations in gastrointestinal motility, visceral hypersensitivity and neuro-enteric dysregulation, inflammation, bile acid malabsorption, increased intestinal permeability, alterations in fecal microbiota, and genetic predisposition.
As the exact cause of IBS remains uncertain, available therapies tend to focus on relieving symptoms rather than treating the root cause. These therapies include dietary modification (such as high-fiber diets, gluten-free diets, and elimination diets), medications (such as antispasmodics, bile acid sequestrants, and laxatives), and mind-body techniques (such as hypnotherapy and cognitive behavioral therapy).
Peppermint oil is a naturally occurring carminative herb, i.e. it induces the expulsion of gas from the stomach and intestines and acts as an antispasmodic, causing relaxation of the gastrointestinal smooth muscle by blocking calcium channels. Its antispasmodic effects combined with its antimicrobial, anti-inflammatory, antioxidant, immunomodulating, and anesthetic properties make it potentially useful for the treatment of IBS.
Several systematic reviews and meta-analyses have reported that peppermint oil may be an effective treatment for IBS. However, earlier reviews included trials with poor methodological designs, while more recent reviews reported conflicting results with regard to the potential adverse effects of peppermint oil. The study under review is a meta-analysis that aimed to determine the effect of peppermint oil on abdominal pain and global symptoms of IBS while also evaluating its possible side effects.
Irritable bowel syndrome (IBS) is a gastrointestinal disorder characterized by recurrent abdominal pain and altered bowel habits. It is the most common functional gastrointestinal disorder. As the exact cause of IBS remains unclear, current treatment is aimed at symptom relief. Peppermint oil is a naturally occurring herb with several properties that may be relevant for the treatment of IBS. The study under review is a meta-analysis that aimed to assess the efficacy and safety of peppermint oil for treating abdominal pain and global symptoms of IBS.
Other Articles in Issue #54 (April 2019)
NERD Mini: What’s magnesium good for?
In this NERD Mini, we give a quick summary of a recent umbrella review's findings concerning which of magnesium's many purported effects are most well supported by the evidence.
Investigating arginine for erectile dysfunction
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Does physical activity prevent depression or does depression prevent physical activity?
The evidence is pretty clear that depression and low physical activity are correlated. This Mendelian randomization study explored whether this link is causal, and in which direction the causal arrow points.
A D-fence against cancer?
This recent meta-analysis examined whether vitamin D supplementation influenced the risk of getting, and the risk of dying from, cancer. It incorporates the latest research into the matter, including VITAL.
Does cinnamon spice up weight loss?
There are some mechanistic reasons to think that cinnamon may help shed some pounds. This recent meta-analysis found an effect, but the significance of its impact is open to question.
NERD Mini: Folic acid intake and neural tube defects
Neural tube defects are potentially serious problems for developing embryos. Its risk is lowered, but not eliminated, by mothers-to-be getting enough folic acid. This NERD Mini explores a recent meta-analysis examining how folate levels are impacted by folic acid intake.
The (mild) health risks of energy drinks
Energy drinks can make a small, potentially negative impact in certain metabolic measures in young, relatively healthy people. But do these changes really matter?