However, researchers only recently have identified non-celiac gluten sensitivity as a separate, distinct condition, and many in the medical field are waiting for confirmation of those still-new research findings before accepting gluten sensitivity as a possible diagnosis.
Given all that, plus the fact that there's no accepted test for gluten sensitivity, it's impossible to say for sure how many people may actually be gluten-sensitive. However, three prominent researchers in the field Dr. Alessio Fasano, Dr. Kenneth Fine and Dr. Rodney Ford recently spoke with me and speculated on what the percentages might be. Just note before you read on that the percentages they mention are based on their own (largely unpublished) research, and don't represent established medical opinion.
Fasano: Gluten Sensitivity May Affect 6% to 7% Overall
Dr. Fasano, director of the University of Maryland Center for Celiac Research, published the first study looking at the molecular basis for gluten sensitivity and how it differs from celiac disease. He also participated in the research concluding that celiac disease incidence is one in every 133 people.
According to Dr. Fasano, gluten sensitivity potentially affects far more people than celiac disease. He estimates about 6% to 7% of the U.S. population may be gluten-sensitive, meaning some 20 million people in the United States alone could have the condition.
Symptoms of gluten sensitivity in this population can include digestive problems, headaches, rashes and eczema-like skin symptoms, brain fog and fatigue, Dr. Fasano says. Almost one-third of those he's diagnosed as gluten-sensitive report brain fog and headaches as symptoms, he says.
Drs. Ford, Fine Say Percentage Could Be Far Higher Up To 50%
Dr. Ford, a pediatrician in Christchurch, New Zealand and author of The Gluten Syndrome, says he believes the percentage of people who are gluten-sensitive actually could be much higher potentially between 30% and 50%.
"There are so many people who are sick," he says. "At least 10% are gluten-sensitive, and it's probably more like 30%. I was sticking my neck out years ago when I said at least 10% of the population is gluten-sensitive. My medical colleagues were saying gluten sensitivity didn't exist. We'll probably find it's more than 50% when we finally settle on a number."
Dr. Fine, a gastroenterologist who founded and directs the gluten sensitivity testing service Enterolab, agrees that gluten sensitivity probably affects half the population.
Another large percentage of Americans have autoimmune disorders, irritable bowel syndrome, chronic headaches and/or microscopic colitis, which place them at high risk for gluten sensitivity. About 60% to 65% of people with those conditions test positive for gluten sensitivity through Enterolab, Dr. Fine says.
Meanwhile, about 20% to 25% of people with no symptoms are diagnosed with gluten sensitivity based on Enterolab testing results, Dr. Fine says.
"When we did the math, we came up with the number of about one in two are gluten-sensitive," he says.
Meanwhile, Dr. Fine says he believes the one in 133 estimate for people who have celiac disease may be too high "I think it's more like one in 200. I'm fully aware of the one in 133 study, but that was an invited and somewhat biased selection." Other studies have placed the incidence of celiac disease at around one in 200 people to one in 250 people, and Dr. Fine says he thinks those are more accurate.
What Do These Gluten Sensitivity Numbers Mean?
At the moment, these potential percentages of people who may have gluten sensitivity represent pure speculation on the part of these physicians and researchers the studies simply haven't been done to prove whether they're accurate or far-fetched.
Fasano A. et al. Divergence of gut permeability and mucosal immune gene expression in two gluten-associated conditions: celiac disease and gluten sensitivity. BMC Medicine 2011, 9:23. doi:10.1186/1741-7015-9-23.
Fasano A. et. al. Spectrum of gluten-related disorders: consensus on new nomenclature and classification. BMC Medicine. BMC Medicine 2012, 10:13 doi:10.1186/1741-7015-10-13. Published: 7 February 2012