re: Are gluten allergies more common now than they used to be?

Agree that the percentage of people who are truly celiac is pretty small, but a not insignificant number of people are gluten sensitive. For the "sensitive", a reduced wheat diet is beneficial.

The overwhelming majority of those who improve on gluten free diets are experiencing a calorie reduction in the carbs/sugars intake....they'd probably see improvement if they eliminated refined sugars and kept the gluten. Nearly all of the supermarket breads contain added sugar; ditto for crackers, breakfast carbs (granola, cereal, bars, etc), and dessert baked goods.