Is perceived intolerance to milk and wheat associated with the corresponding IgG and IgA food antibodies? A cross sectional study in subjects with morbid obesity and gastrointestinal symptoms.

BMC gastroenterology. 2018;18(1):22
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Dairy and gluten are the most common triggers of irritable bowel syndrome (IBS) in the general population. Food intolerance is generally detected by IgG antibodies, but the test is controversial. In this cross-sectional study, 97 obese subjects (82.4% women) were included, of which 72.1% had gastrointestinal symptoms, 35.7% had IBS, 31.4% had symptoms of milk intolerance, 28.6% had symptoms of wheat intolerance, and 15.7% had symptoms of intolerance to both milk and wheat. The study examined the association between IgA and IgG antibodies corresponding to milk and wheat in subjects with and without gastrointestinal issues and with and without perceptions of food sensitivity. The results of this study found no association between s-IgG and s-IgA antibodies and perceived food intolerances to milk and wheat among morbidly obese subjects. Although IgA against gliadin correlated with increased levels of zonulin, a marker of intestinal permeability, tight-junctional gut permeability inversely correlated with wheat intolerance. Furthermore, the study results revealed a significant correlation between hypothyroidism and IgG against wheat and a marginal correlation between hypothyroidism and IgG against gluten. Further robust research is needed to confirm these findings. Healthcare professionals can use the results of this study to understand the current developments and the controversy surrounding food intolerance testing.


BACKGROUND Serum IgG and IgA food antibodies have been used for dietary advice to subjects with gastrointestinal symptoms and perceived food intolerance, but the role of these antibodies in mediating intolerance is controversial. The present study investigated associations between perceived gastrointestinal intolerance to milk-or wheat and the corresponding s-IgG and s-IgA food antibodies in subjects with morbid obesity. METHODS Subjects with morbid obesity (BMI ≥ 40 kg/m2 or ≥35 kg/m2 with obesity-related complications) were included. Irritable Bowel Syndrome (IBS) was diagnosed based on the Rome III criteria. Severity of specific gastrointestinal symptoms were measured with the Gastrointestinal Symptom Rating Scale (GSRS)-IBS. S-IgG against cow's milk, cheese, wheat and gluten, and s-IgA against casein and gliadin were measured. RESULTS Ninety-seven subjects (80 females) with mean age 45 (SD 8.4) years were included, 70 had gastrointestinal complaints, 25 had IBS, and 22 and 20 reported milk- and wheat- intolerance respectively. There were no significant differences in serum concentrations or proportions of subjects above defined cut-off values for the antibodies between subjects with and without gastrointestinal complaints. In the group with gastrointestinal complaints, no significant differences were found between subjects with and without perceived food intolerance. Except for a significant correlation between IgG against cheese and GSRS-diarrhea (Rho: -0.25, P = 0.04), no significant correlations were found between the antibodies and type or degree of gastrointestinal symptoms, including IBS. CONCLUSIONS The study showed no associations between perceived milk or wheat intolerance and the corresponding s-IgG and s-IgA food antibodies in subjects with morbid obesity.

Lifestyle medicine

Patient Centred Factors : Triggers/Milk and wheat
Environmental Inputs : Diet
Personal Lifestyle Factors : Nutrition
Functional Laboratory Testing : Blood
Bioactive Substances : Milk ; Wheat ; Gluten ; Dairy

Methodological quality

Jadad score : 0
Allocation concealment : Not applicable
Publication Type : Journal Article