Now, as clinicians scramble to get a handle on the gluten problem, researchers are turning attention to another potential culprit in chronic digestive disease: FODMAPS. The acronym stands for fermentable, oligo-, di-, mono-saccharides and polyols, which are poorly-absorbed short-chain carbs found in wheat, rye and other grains.
In some people, FODMAPS ferment during passage through the GI tract, and form copious amounts of gas that can be very painful. A new Australian study suggests that in many cases of suspected gluten sensitivity, it may actually be FODMAPS that are causing the problem.
Because FODMAPS tend to run together with gluten in many foods, it can be challenging to determine precisely what's triggering symptoms like bloating and flatulence in a particular case. On the other hand, FODMAPS are also found in many other non-gluten foods contain FODMAPS—milk, asparagus, celery, watermelon to name just a few. The FODMAP theory could provide an answer in cases where patients do not find relief after going gluten-free.
FODMAPS are found in many common foods—including many otherwise healthy foods such as milk, legumes, cashews, pistachios, asparagus, artichokes, sweet corn, onions, garlic, celery, apples, pears, mango, watermelon, nectarines, peaches and plums.
FODMAPS tend to be poorly absorbed in post people. In some—for reasons that are not yet clear—there is a high level of FODMAP fermentation in the gut, leading to severe abdominal distension.
Investigators at Monas University, Victoria, put 37 subjects with symptoms of "non-gluten celiac sensitivity (NCGS)" on a low-FODMAP diet for 2 weeks. The diet involved limiting consumption of foods known to have high concentrations of FODMAPS.
The subjects then underwent double-blind crossovers involving three different diets: high-gluten, low-gluten, and gluten-free diets for a week, followed by a washout period of at least 2 weeks.
A 3-day crossover rechallenge with gluten was then given to 22 participants. For all participants, gastrointestinal symptoms significantly improved during the periods of reduced FODMAP intake.
During the periods when gluten-containing foods were added back, only 8% in of subjects had symptom increases. During the 3-day rechallenge, symptoms increased by similar levels among groups. The investigators found no evidence of specific or dose-dependent effects of gluten in NCGS patients who are first placed on a low-FODMAP diet (Biesiekierski JR, et al. Gastroenterology. 2013;145:320-328).
"Even though this study is very small, it is well-designed and can't be ignored," said Dr. Jeffrey Hertzberg, in a review of the study posted on the ConsultantLIVE website last month. Dr. Hertzberg, of the University of Minnesota's Medical Industry Leadership Institute, believes the FODMAP story will have increasing clinical importance.
"We're probably gong to be hearing more about FODMAPS in the coming years.
The Monash group is not the only team suggesting that FODMAPS play a role in common digestive disorders, though the theory does seem to be particularly interesting to investigators "down under." Researchers at the University of Otago, Christchurch, NZ, just published a study of 90 patients with Irritable Bowel Syndrome showing that 16 months on a low-FODMAP diet produced marked decreases in symptoms of flatulence, bloating and diarrhea (deRoest RH, et al. Int J Clin Pract. 2013;67(9):895-903).
While it is too soon to draw definitive conclusions about the role of FODMAPS in common digestive complaints, the available data do suggest a new angle on the issue.