Since I adopted a Paleo diet, I have not been eating grains. And, while I am no longer following the GAPS diet, grains are also forbidden on the Paleo Autoimmune Protocol (which I will refer to as AIP during the remainder of this post). But, whereas a more mainstream Paleo diet avoids grains since humans didn’t eat grains during the Paleolithic, on the AIP we are told not to eat them because they are highly allergenic and have relatively low nutritional content. So, today I will outline the some of the different reasons why those following the AIP should give up grain.
One reason those following the AIP don’t eat grains is due their high phytate content. Phytate is created when phytic acid binds to minerals. This means that any minerals (iron, calcium, potassium, magnesium and zinc) found in grains can’t be absorbed via the digestive system, which is why it is considered an anti-nutrient. A direct result of consuming grains is mineral deficiencies, as if you depend on grains for your nutritional source of important minerals, your body’s stores get depleted because your body isn’t able to digest the phytate. Another reason high phytate grains are avoided is because phytate can irritate the gut, resulting in increased intestinal permeability or what is known as leaky gut. In addition, the excessive amounts found in grains can interfere with digestive enzymes.
But, the main reason grains are strictly avoided is due to substances called toxic lectins. There are two main classes: prolamin and agglutinins.
Prolamins are a class of proteins found in grains and pseudo-grains that are questionable for health. They include wheat, barley, quinoa, oats, and rice. Specific examples include, gliadin in wheat; zein in corn; and orzenin in oats. Part of the problem with prolamins, is that our digestive enzymes are not able to fully break them down. This is for two reasons: these proteins structures are incompatible with our digestive enzymes; and prolamin containing seeds also have protease inhibitors (substances that stop enzymes from breaking down proteins). So, prolamin particles can cross the gut barrier, thereby damaging it and causing leaky gut.
The other class of toxic lectins are agglutinins. These are hard to digest as our bodies don’t produce the proteolytic enzymes (enzymes that can break apart proteins) needed to reduce proteins into their constituent amino acids. They are not deactivated by cooking, and they cause leaky gut. Agglutinins stimulate both the adaptive and innate immune system.
Another reason grains and pseudo-grains are avoided on the AIP is that they contain substances that inhibit digestive enzymes. These are protease and amylase inhibitors. Protease inhibitors stop proteins from being broken into individual amino acids; and amylase inhibitors infer with the enzymes that digest starches. So, eating grains can cause digestive enzymes to become unbalanced, thereby leading to leaky gut. Another effect is that, when our bodies are full of indigestible food, is that undigested food becomes food for our gut flora, which can cause an imbalance of our gut flora, also leading to leaky gut.
There is another reason to avoid both non-gluten grains and pseudo-grains: cross-reactivity with gluten. Cross-reactivity means your body sees another protein, say the casein in milk, and that causes it to react as if it were gluten, with an immune response. A recent study showed cross-reactivity with 25 common foods, including millet, corn, rice, sorghum, potatoes, and dairy proteins.
Finally, many non-gluten grains are cross-contaminated with gluten containing grains. They can be contaminated through agricultural practices, i.e. crop rotation; or through the manufacturing process, i.e. sharing equipment, etc.
So, grains are avoided because they are highly allergenic due to the toxic lectins, prolamin and agglutinin; they contain enzyme inhibitors; have low nutritional content due to the high phytate levels; and all these factors mean they can result in leaky gut. So, I hope you now understand why grains and pseudo-grains are avoided on the Autoimmune Protocol.
Source: I am indebted to The Paleo Approach by Sarah Ballantyne for the preparation of this blog post.