Research indicates its may not be a placebo, eg: "Gluten Causes Gastrointestinal Symptoms in Subjects Without Celiac Disease: A Double-Blind Randomized Placebo-Controlled Trial" (The American Journal of Gastroenterology 106, 508-514 (March 2011))
A potential contributing factor for the recent rise might the use of drugs such as be Accutane/Isotretinoin. 2 million US people have taken Accutane since 1982, and recently it has been linked to intestinal/bowel issues (including increased sensitivity to gluten).
A potential contributing factor for the recent rise might the use of drugs such as be Accutane/Isotretinoin. 2 million US people have taken Accutane since 1982, and recently it has been linked to intestinal/bowel issues (including increased sensitivity to gluten).