Celiac Disease and Gluten-Free Oats: A Canadian Position Based on a Literature Review

Table 1

Clinical studies of the effects of oats on children with celiac disease from January 2008 to January 2015.

Reference authors, year of publication	Number of subjects tested	Oats exposure	Amount of oats	Lab tests	Biopsy	Drop-out rate	Conclusion
Koskinen et al., 2009, Finland [18]	13 in remission with open oats challenge; 10 in remission wheat, rye, barley, and oats	2 years	50 g/day	TTG IgA	Small-bowel biopsies (IgA deposits) at baseline + 6 m + 24 m: No signs of immune activation or relapse of CD; No detrimental effect on intestinal mucosal villous morphology and IEL density	2 children experienced abdominal pain but with normal biopsy	Pure oats can be safely added to the GFD of children with CD
Gatti et al., 2013, Italy [19]	Group A-B = 154; Group B-A = 152	15 months [6 months oats or placebo (A-B); 3 months washed-out; 6 months oats or placebo (B-A)]	Up to 40 g/day	TTG IgA, antigliadin IgG, and antiavenin Abs	No biopsy	55/154 (36%) enrolled in group A-B and 42/152 (28%) enrolled in group B-A No information provided about reasons for withdrawals	Addition of noncontaminated oats in the treatment of children with CD does not cause changes in intestinal permeability and gastrointestinal symptoms
Tapsas et al., 2014, Sweden [20]	282 (89%) consumed oats and 259 (82%) pure oats; 34 (11%) did not consumed oats	Mean = 6.9 years	Not specified	No serology	No biopsy	34 (11%) did not consume oats. For those having tried oats () but stopped, 8 did not like the taste, 2 reported abdominal pain and loose stools, 2 gave no specific reason, and 1 did not answer	Most patients did not report adverse effects after long-term consumption of oats
Sjöberg et al., 2014; (Same patients as for study published in 2004 by Högberg et al. [16]), Sweden [28]	15 GFD with uncontaminated oats (GFD-oats); versus 13 GFD without oats (GFD-std)	Mean = 13 months	Median = 20 g/day; Range = 3–43 g/day	TTG IgA, antigliadin IgG; Expression levels of mRNAs for 22 different immune effector molecules and tight junctions proteins (markers of mucosal inflammation)	No difference between 2 groups in intestinal histology score (Marsh score)		No difference between 2 groups in terms of serology biomarkers and intestinal histology score; Normalisation of genetic markers of regulators of inflammation in some pediatric patients with CD maybe significantly reduced in the GFD-oats group compared to the GFD-std group; Altered functions of the epithelium in the small intestine mucosa “support the notion that a fraction of CD patients tolerate oats poorly”
Tjellström et al., 2014; (Same patients as for study published in 2004 by Högberg et al. [16]), Sweden [29]	34 GFD with uncontaminated oats (GFD-oats); versus 37 GFD without oats (GFD-std)	12 months	25–50 g/day	Endomysial IgA and IgG, antigliadin IgA, and TTG IgA; Faecal short chain fatty acids (SCFA) concentration (marker of gut microflora metabolism) and SCFA fermentation index (marker of intestinal inflammation)	At baseline: small bowel enteropathy consistent with CD; at 12 months: all children in clinical remission except one child (GFD-std group) who did not undergo a control biopsy	None; However, all children in the study did not deliver faecal samples and some samples were too small to permit analysis; distribution of missing samples was evenly distributed between the 2 study groups	Normalisation of small bowel mucosal architecture and decreasing celiac serology markers However, total SCFA remained at a high level in the GFD-oats group compared to the GFD-std group

Abs: antibodies; CD: celiac disease; GFD: gluten-free diet; IEL: intraepithelial lymphocytes; IgA: immunoglobulin A; IgG: immunoglobulin G; TTG: tissue transglutaminase; GFD-std: standard GFD without oats; GFD-oats: GFD with uncontaminated oats.