Many celiacs have negative reactions to soy, even if they are not directly allergic to it. The reason behind it is, as always the dreaded cross contamination.
Although common sense tells us that soy doesn’t contain gluten and therefore it’s safe to consume it, the reality is that soy is one of the worst offenders when it comes to celiac disease and gluten sensitivity.
How is this possible? well, the blame can be directed at farming practices.
You see, the same fields that are used to grow wheat, are also used to grow soy. Usually what they do is once wheat has been grown and harvested, then soy is planted on the same field, and once it is haversted, then wheat is planted on the same field again. Other times both fields (one for wheat and other for soy) are right beside eachother. So from the very beginning is quite possible for soy to become cross contaminated, but this is only the beginning of a long cross contamination process.
The same tools are used to plant, treat, and harvest both soy and wheat. The same trucks are used to transport both of them, the same storage facilities are used to store both of them, etc. So basically everything that could be done to cross contaminate soy is done.
A study donde by Tricia Thompson in 2010 found that soy flour contained 2,925 parts per million of gluten when in a gluten free food shoud contain 20 parts per million or less. Although many people react to even less than that.
These practices I talked about have been documented on the United States, however it is quite possible that other countries follow them too or very similar ones. The next graphs show the contries that produce the most amount of soybeans in the world, and their exports. Although these data is dated between 2011 and 2013, it gives us a very good idea of the whole picture.
Why am I showing you this?
Because even if you don’t live in the United States, it is very possible that many of your soy products are made with soy that comes from the US, and therefore it is soy that has been through the farming process I described earlier. Which makes those soy products unsafe for consumption for people with gluten sensitivity or celiac disease.
What can you do?
First you must find out if you are not allergic or sensitive to soy, because soy is already an allergenic food. Once you know if you are not allergic to soy, and still you have negative reactions to it, then it is possible that the problem rellies in cross contamination.
So thee next thing you should do is find certified gluten-free soy products. A gluten free certifications implies very high standards in the process of choosing raw materials, and food processing.
Gluten Contamination of Grains, Seeds, and Flours in the United States: A Pilot Study.