Objectives: Celiac disease is an enteropathy triggered by dietary gluten found in wheat, rye, and barley. Treatment involves a strict gluten-free diet (GFD). Quinoa is a highly nutritive plant from the Andes that has been recommended as part of a GFD. However, in-vitro data suggested that quinoa prolamins can stimulate innate and adaptive immune responses in celiac patients. Therefore, we aimed to evaluate the in-vivo effects of eating quinoa in adult celiac patients.
Methods: Nineteen treated celiac patients consumed 50 g of quinoa every day for 6 weeks as part of their usual GFD. We evaluated diet, serology, and gastrointestinal parameters. Furthermore, we carried out detail histological assessment of 10 patients before and after eating quinoa.
Results: Gastrointestinal parameters were normal. The ratio of villus height to crypt depth improved from slightly below normal values (2.8:1) to normal levels (3:1), surface-enterocyte cell height improved from 28.76 to 29.77 μm and the number of intra-epithelial lymphocytes per 100 enterocytes decreased from 30.3 to 29.7. Median values for all the blood tests remained within normal ranges, although total cholesterol (n=19) decreased from 4.6 to 4.3 mmol/l, low-density lipoprotein decreased from 2.46 to 2.45 mmol/l, high-density lipoprotein decreased from 1.8 to 1.68 mmol/l and triglycerides decreased from 0.80 to 0.79 mmol/l.
Conclusions: Addition of quinoa to the GFD of celiac patients was well tolerated and did not exacerbate the condition. There was a positive trend toward improved histological and serological parameters, particularly a mild hypocholesterolemic effect. Overall, this is the first clinical data suggesting that daily 50 g of quinoa for 6 weeks can be safely tolerated by celiac patients. However, further studies are needed to determine the long-term effects of quinoa consumption.