"I believe you've put the cart before the horse: gluten does not cause celiac. It is a genetic disorder that can manifest in various ways. People with celiac react to gluten."
Yes, that's the conventional wisdom in the medical community. I happen to think it's wrong.
My wheat analogy is to poison ivy. Both contain chemicals that cause the body to initiate an auto-immune response, attacking its own tissues. In poison ivy, this is most commonly the skin, for wheat in celiac disease, it's the mucosal lining of the small intestine, although it can affect any tissue in the body. I can't imagine what effect eating poison ivy would have on the lining of the small intestine if you ate it, but it can't be good.
Neither wheat nor poison ivy affects 100% of the population.
"If ingested, poison ivy can produce severe gastrointestinal effects. Some individuals, however, can consume poison ivy without effect, apparently because of a lack of reactivity in the digestive mucosa."
One manifestation of celiac disease is a skin condition called dermatitis herpetiformis. This is commonly misdiagnosed as poison ivy.
Yet the medical community regards poison ivy as a toxic plant, best avoided. No one considers the reaction to poison ivy to be a human "genetic condition", although of course it is. Dogs and cats aren't susceptible to poison ivy, for instance. No one proposes that you ought to eat it.
So the difference between wheat and poison ivy is that wheat is a low-grade toxic plant that most people tolerate to some degree. Poison ivy is a high-grade toxic plant that almost no-one tolerates.
Interestingly, both wheat and poison ivy produce what's known as "Type IV Hypersensitivity". If you go look at the Wikipedia page on the topic, most of the causes of type IV hypersensitivity are either poison ivy or wheat-caused or -associated illnesses like celiac, Type 1 diabetes, and Hashimoto's thyroiditis. I'll wager the list of poison-ivy-related illnesses would be longer if people were in the practice of eating it.
I read in one journal that celiac is the most common genetically-determined condition in the human species. But as I think I've demonstrated, poison ivy sensitivity is far more common.
The most commonly accepted estimate of celiac prevalance is 1 in 133 people. I've heard estimates of wheat sensitivity that go up to 99% of the population. It's clearly far higher than 1 in 133. My diverticulitis, for instance, is clearly caused by wheat. I can reproduce the symptoms at will be eating it. Diverticulitis affects 65% of the population by the time they're 80, and becomes common in populations after wheat is introduced.
Eating wheat is a mistake. You shouldn't eat toxic plants that humans are not adapted to eat.