You probably know what yoga is. But what is FODMAP? It stands for fermentable oligosaccharides, disaccharides, monosaccharides and polyols, more commonly known as carbohydrates. In essence, FODMAPs are carbohydrates found in a wide range of foods including onions, garlic, mushrooms, apples, lentils, rye and milk. These sugars are poorly absorbed, pass through the small intestine and enter the colon . There they are fermented by bacteria a process that produces gas which stretches the sensitive bowel causing bloating, wind and sometimes even pain. This can also cause water to move into and out of the colon, causing diarrhoea, constipation or a combination of both. Irritable bowel syndrome (IBS) makes people more susceptible to such problems.
During a low FODMAP diet these carbohydrates are eliminated usually for six to eight weeks. Subsequently, small amounts of FODMAP foods are gradually re-introduced to find a level of symptom-free tolerance. The question is, does the low FODMAP diet work?
This study examined the effect of a yoga-based intervention vs a low FODMAP diet on patients with irritable bowel syndrome. Fifty-nine patients with IBS undertook a randomised controlled trial involving yoga or a low FODMAP diet for 12 weeks. Patients in the yoga group received two sessions weekly, while patients in the low FODMAP group received a total of three sessions of nutritional counselling. The primary outcome was a change in gastrointestinal symptoms (IBS-SSS). Secondary outcomes explored changes in quality of life (IBS-QOL), health (SF-36), perceived stress (CPSS, PSQ), body awareness (BAQ), body responsiveness (BRS) and safety of the interventions. Outcomes were examined in weeks 12 and 24 by assessors “blinded” to patients’ group allocation.
No statistically significant difference was found between the intervention groups, with regard to IBS-SSS score, at either 12 or 24 weeks. Within-group comparisons showed statistically significant effects for yoga and low FODMAP diet at both 12 and 24 weeks. Comparable within-group effects occurred for the other outcomes. One patient in each intervention group experienced serious adverse events and another, also in each group, experienced nonserious adverse events.
The authors concluded that patients with irritable bowel syndrome might benefit from yoga and a low-FODMAP diet, as both groups showed a reduction in gastrointestinal symptoms. More research on the underlying mechanisms of both interventions is warranted, as well as exploration of potential benefits from their combined use.
Technically, this study is an equivalence study comparing two interventions. Such trials only make sense, if one of the two treatments have been proven to be effective. This is, however, not the case. Moreover, equivalence studies require much larger sample sizes than the 59 patients included here.
What follows is that this trial is pure pseudoscience and the positive conclusion of this study is not warranted. The authors have, in my view, demonstrated a remarkable level of ignorance regarding clinical research. None of this is all that unusual in the realm of alternative medicine; sadly, it seems more the rule than the exception.
What might make this lack of research know-how more noteworthy is something else: starting in January 2019, one of the lead authors of this piece of pseudo-research (Prof. Dr. med. Jost Langhorst) will be the director of the new Stiftungslehrstuhl “Integrative Medizin” am Klinikum Bamberg (clinic and chair of integrative medicine in Bamberg, Germany).
This does not bode well, does it?