When it comes to the medical literature, I'm even cautious about doctors claims. Dr. Oz is a doctor, but he's a cardiac surgeon. So when he makes claims about the healthiness of palm oil (which is solid at room temperature, and is only healthy by comparison to lard), he is abusing his credibility as an MD.
Here's a summary of the literature about Celiacs which my wife linked me to: https://www.clinicalkey.com/topics/pediatrics/celiac-disease...
You'll note in the epidemiology section that Celiacs to genetics. The disease is prevalent primarily in western european populations (or populations descended from western europe), and has actually shown a decrease in non-european descended populations.
(My wife also notes that in the Infant Diet section it does say that if you feed gluten to infants it can increase their chance of Celiac's. This is true if you have genes which predispose you to Celiac's. If you do not have the genes, you can't develop Celiac's. And even if you do have the genes, you can go throughout your life w/o developing Celiac's, although apparently being fed gluten early in life does increase your risks. Seems more like a thing about feeding infants than it does about gluten really.)
Edit: My wife also points out that Celiacs diagnoses prior to 1997 were done via biopsy (which is of course, invasive, when we're talking about intestines). After 1997, and the availability of a simple blood screening test, testing for Celiac's has become cheaper, easier, and more prevalent. That certainly must contribute to the increased number of diagnoses.