A Tale of Two Gluten Studies

“It was the best of times,

it was the worst of times,

it was the age of wisdom,

it was the age of foolishness,

it was the epoch of belief,

it was the epoch of incredulity,

it was the season of Light,

it was the season of Darkness,

it was the spring of hope,

it was the winter of despair,

we had everything before us, we had nothing before us, we were all going direct to Heaven, we were all going direct the other way…”

A couple recent gluten studies made me think of Dickens’ opening lines from “A Tale of Two Cities,” which describe the concurrence of contradictory states of being and consciousness in 18th century Western Europe. That’s people for ya. We can be miserable and happy at the same time. We can believe something despite evidence to the contrary staring us in the face. You’ll see it in online arguments, especially regarding subjects whose research luminaries publish in journals that offer online access to study abstracts for us plebs. That’s why comment board arguments between two opposing camps touting completely contradictory information stretch endlessly – because they can always trot out URL after URL of an abstract that appears to support their point. For every study, there’s a counter study.

Back to gluten. Two studies, one negative and one positive. The “negative,” a double blind, placebo-controlled RCT, found that gluten caused symptoms of gastrointestinal distress in certified non-celiacs with irritable bowel syndrome. The “positive” found that putting people on a gluten-free diet lowered levels of beneficial gut flora, potentially impairing immune function. Study, counter study. What can you do but throw up your hands, sigh, and resign yourself to never knowing the real truth?

You can look a bit closer. It’s reasonable to assume that the gluten RCT, being randomized and controlled and all, offers valuable information. Both groups had IBS and were eating gluten-free diets, except for the experimental group’s two slices of actual wheat bread and muffin each day (gluten included); the control group got placebo baked goods. 68% of the gluten group reported no improvements in IBS symptoms, while just 40% of the gluten-free group reported none. Put another way, 60% of the truly gluten-free felt better, while just 32% of the faux gluten-free felt better. In the gluten group, pain, bloating, and tiredness increased, stool consistency satisfaction decreased, and general negative symptoms got worse and more pronounced.

The gut flora study doesn’t even address gluten itself when you look closer. It’s addressing the reduction in dietary polysaccharides when following a gluten-free diet. Beneficial gut flora had fewer polysaccharides to feed on with whole wheat out of the diet.

You gotta wonder what exactly these gluten-free diets consisted of. I don’t know about the gluten-free folks you know, but the ones I come across who identify specifically as gluten-free tend to eat a lot of gluten-free treats. Flourless cakes, rice crackers, gluten-free brownies, weird gluten-free pizzas made with bean/rice/corn flour. They’re gravitating toward the boxed snacks and treats and breads so long as the “GF” label graces the box. They’re chowing down on ultra-processed, refined carbohydrates, with rice products dominating. There’s not much for the gut flora to work with there.

Check it out: “This study included 10 healthy subjects (30.3 years-old), who were following a GFD over one month by replacing the gluten-containing foods they usually ate with certified gluten-free foods (with no more than 20 parts per million of gluten).” So, yeah, they replaced gluten foods with “certified gluten-free foods,” which means crap-in-a-box and rice flour brownies. Meat and veggies may not contain gluten, but they aren’t “certified gluten-free.” They don’t get the nifty label. Gluten doesn’t have a wondrous effect on human gut flora. It’s not a magic protein. It’s the food that most people use (and, indeed, become obsessed with) to replace gluten-containing foods doing the damage. Poorly constructed gluten-free diets might negatively affect gut flora and immune function, but the Primal way of eating is not a poorly constructed gluten-free diet.

Although the authors were interested in understanding and overcoming potential downsides of typical gluten-free diets (they suggest dietary counseling, probiotics, and increased polysaccharide intake), this is the type of study that will get thrown around haphazardly in an argument against gluten avoidance in the general population. “See? Gluten-free diets reduce immune function and kill good gut flora!” accompanied by a fancy embedded link. It’s nonsense, of course, but it’s what we’re up against. Be prepared.

See? When you look more closely, some of those contradictory studies start looking complementary. It’s good to understand why, not for online battles (necessarily) but for your own enrichment.

About the Author

Mark Sisson is the founder of Mark’s Daily Apple, godfather to the Primal food and lifestyle movement, and the New York Times bestselling author of The Keto Reset Diet. His latest book is Keto for Life, where he discusses how he combines the keto diet with a Primal lifestyle for optimal health and longevity. Mark is the author of numerous other books as well, including The Primal Blueprint, which was credited with turbocharging the growth of the primal/paleo movement back in 2009. After spending more than three decades educating folks on why food is the key component to achieving and maintaining optimal wellness, Mark launched Primal Kitchen, a real-food company that creates flavorful and delicious kitchen staples crafted with premium ingredients like avocado oil. With over 70 condiments, sauces, oils, and dressings in their lineup, Primal Kitchen makes it easy to prep mouthwatering meals that fit into your lifestyle.

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