Up to 70 percent of adults are intolerant of dairy, gluten, or other dietary triggers. Learn if you’re one of them. Digestive, skin, joint, energy, and mood problems may be your first clue.
It took a long time for me to identify that I had a problem with gluten — because for a long time I didn’t have one. Or, at least, I didn’t think I did.
Looking back now, it seems so obvious. My dad had a gluten intolerance back in the 1960s, before anybody had heard of such a thing.
A few years ago, genetic testing revealed that Dad carried (and passed along) a celiac gene called HLA-DQ2 — one of two genes known to predispose people to gluten-related problems.
Those who have these genes and don’t avoid gluten-containing foods are dramatically more likely to develop celiac disease, as well as a host of other health problems.
I now know that I carry this gene. But throughout my childhood, it lay dormant. I grew up eating my mom’s homemade wheat bread, pasta, and other glutenous foods with impunity.
My genetic switch got flipped in early adulthood, just after college, when I was living in France on a Fulbright scholarship. Residing in Paris on a half-time salary without any social support left me stressed to the max, and I relied on cheap baguettes for a lot of my daily sustenance.
Without realizing it, I had created the perfect inflammatory storm: elevated stress plus elevated exposure to an irritant — in this case, gluten. This triggered a latent genetic predisposition, opened holes in my intestinal lining, and sent my body into a tizzy.
At the time, though, all I knew was that my skin was suddenly breaking out in cystic acne; my back hurt; my digestive system was off; my face was puffy; I felt depressed, brain-fogged, inflamed; and I was putting on weight.
It wasn’t until more than a year after I got home, wound up in a car accident, and went to see a chiropractor that I had an inkling that any of my physical problems might be related to what I was eating.
On my first visit, noting the assortment of health concerns I’d listed on my intake questionnaire, and evaluating the state of inflammation along my spinal column, my chiropractor asked me, “Do you have gluten sensitivities?”
Having never previously heard the word “gluten” uttered by anyone other than my father (this was the early 1990s), I was taken aback. “Um, no,” I said. “But it’s weird you should ask, because my father has always had trouble with gluten.”
“Aha,” she said. “Then I suggest you stay off it for a few weeks and see how you feel.” She handed me instructions on how to do an elimination diet and sent me to the store for groceries.
Long story short, within three days, I was feeling like a new person. My skin was clearing, my face was noticeably less puffy, my digestion was improved, and my brain fog had lifted. And that was when gluten and I parted ways for good.
I am fortunate. More than two decades later, genetic testing confirmed the inheritance my chiropractor had guessed at. But had I not been avoiding gluten in the interim, it’s likely I would have developed a number of inflammatory conditions by now, quite possibly including celiac or some other autoimmune disease.
Today, public awareness of food intolerances has entered the mainstream, and research on the topic is advancing rapidly, particularly in the area of gluten sensitivity.
Thanks to research by Alessio Fasano, MD, and others, we now understand at least some of the mechanisms by which gluten triggers intestinal permeability, and, by extension, a host of secondary inflammatory and immune responses (see Revolutionary Resources, below).
We now know that gluten can negatively affect folks without known celiac genes or disease. We also know that intolerances to commonly eaten ingredients like gluten, dairy, soy, corn, and eggs can cause an astonishing array of symptoms.
In one person, eating an intolerance-triggering food may set the stage for allergies and asthma; in another, it might give rise to rheumatoid arthritis, migraines, multiple sclerosis, neurological problems, depression, or psoriasis.
This is a big deal. Psoriasis is an autoimmune disease that affects 7.5 million Americans, and according to the National Psoriasis Foundation, about 25 percent of them show evidence of gluten intolerance. A 2009 study published in the Brazilian Annals of Dermatology showed that among psoriasis patients with gluten sensitivity, adhering to a gluten-free diet improved their symptoms.
Although we’ve learned much in recent years, there’s still a lot of confusion and consternation on the topic of food intolerances. So here I will share with you what I wish more people (especially those with complex chronic diseases and conditions) knew.
Food intolerances are different from food allergies. If you ask your doctor to test you for food allergies, you’ll probably get tested for “IgE-mediated” immune reactions — the kind that cause acute symptoms like sneezing, itching, hives, and anaphylaxis.
Such tests might be helpful, but they won’t tell you anything about delayed, nonallergy intolerances — the kind that trigger digestive distress, dark circles, headaches, and fatigue, as well as skin, joint, and digestive complaints. These are the food intolerances that can both cause leaky gut and result from it; they’re the kind that can give rise to increasingly serious diseases, including autoimmune disorders, over time.
The most common diagnostic labs for non-IgE food reactions are known by the acronyms ELISA, IgG, and IgA. Evidence of food intolerances can also be seen in some fecal and breath tests, and in tests for C-reactive protein (CRP). But more often, they are identified by means of an elimination diet. This involves removing one or more high-potential irritants from your diet for a period of a few weeks, then gradually reintroducing them to see which (if any) trigger a negative reaction in your system.
Food intolerances are common. As with the food allergies (which increased about 50 percent in children between 1997 and 2011), the incidence of food intolerances appears to be rising. Potential causes include changes in agriculture, food production, and processing; changes in our diet, microbiome, and environment; chronic-stress levels; and more.
Whatever the reasons, a surprising swath of the population — based on current research, some experts put the number as high as 40 percent — shows some level of non-celiac gluten sensitivity. Geneticists say that the majority of the world’s population (an estimated 70 percent) lacks the enzyme required to properly digest dairy. Many other people are sensitive to soy, eggs, corn, food additives, or food components like FODMAPs, histamines, and salicylates.
Statistically speaking, that means you are more likely to experience a food intolerance than to be spared one. So, if you are suffering from one or more chronic health complaints, or have been diagnosed with an auto-immune condition, embarking on a simple elimination diet to assess your own level of sensitivity to common food triggers makes sense.
The good news: Your intolerances may not be permanent, particularly if intestinal permeability is to blame. Once you’ve healed your gut, you may be able to go back to enjoying (at least on occasion) some or all of the foods you thought you couldn’t.
There’s only one way to find out.