Should Coeliacs Eat Oats? It Depends on the Oats.
Gut Health and Coeliac Disease | Can coeliacs eat oats?
It is still a matter of controversy whether or not oats are safe for people with coeliac disease. Can coeliacs eat oats? The general consensus at this point seems to be that pure oats are safe for most, but not all, people with coeliac disease. Since oats can easily be contaminated with wheat, rye, and barley during harvest, storage, and various other stages of processing, it has been stressed that the oats be certified as pure according to the Global Oats Protocol. Although the classic 33-amino acid long oligopeptide that acts as the immunogenic stimulus in gliadin had not yet been found in oats, other peptides isolated from oats do activate T-cells isolated from coeliac patients, namely the protein Avenin. A new study performed in Spain by Isabel Comino et al. suggests that it is not that some coeliac patients can’t tolerate all oats, but rather that all coeliac patients can’t tolerate some oats. Their results are reported in the January 2011 issue of GUT: An International Journal of Gastroenterology and Hepatology.
Dr Comina and her colleagues examined nine different cultivars of oats. They exposed each of them to a sensitive monoclonal antibody generated to recognize the toxic 33-mer from gliadin and also measured if each of the oat varieties could elicit an immune response in peripheral blood mononuclear cells from coeliac patients. They wanted to see if they could correlate recognition by the monoclonal antibody to induction of a T-cell response, and found that they certainly could.
The nine varieties of oats were segregated neatly into three groups of three varieties each: those for which the antibody had high affinity, low affinity, and no affinity. This affinity was validated by two different experimental methods, so was not an artefact of the technique chosen. When T cells from patients with coeliac were exposed to extracts of the oat variety the antibody bound to strongest, they proliferated the most and released interferon-gamma, an immunostimulatory cytokine whose aberrant expression is associated with the autoinflammatory disease. In contrast, the oats that didn’t react with the antibody did not elicit these immune responses. The authors note that the avenin – the storage protein in oats – from even the most immunogenic oats they saw bound to this antibody with 40-400 fold less affinity than gliadin (from gluten – the storage protein in wheat).
This study thus leaves us with two valuable conclusions. One is that some oats are more toxic than others, regardless of their purity. And the other is that reactivity with this antibody can be correlated to toxicity, making it a potential tool for evaluating the toxic gluten content of other food.
Coeliac patients are currently advised to do an oat challenge with their health professional to ensure that uncontaminated oats don’t react with them. If you are one of the lucky ones to be able to eat oats, they are a nutritious option compared to the GMO soy, corn, and healthy laden breakfast cereal and snack products currently available to gluten-free consumers.
Now you might have a clearer idea of can coeliacs eat oats?
- Gut doi:10.1136/gut.2010.225268
- Celiac.com 03/14/2011