Is there a dark side to a gluten-free diet (GFD)? With nearly one-third of Americans having tried a gluten-free or gluten-reduced diet in recent years, there is more and more research on both the positive and negative effects of going gluten-free. My friend and colleague, Dr. Tom O’Bryan, recently published an article summarizing this “dark side” of a GFD, including nutritional deficiencies, toxicity, morbidity, mortality, and mental health problems.
Gluten-free products and menus, for instance, are often calorie rich and nutrient poor, significantly lower in protein, magnesium, potassium, vitamin E, folate, and sodium, with suggestive trends toward lower calcium and higher fat. In addition, removing wheat or gluten-containing foods from the diet can contribute to a shift in the intestinal microbiome diversity, leading to a decrease bifidobacterium and lactobacillus, an increase in Enterobacteriaceae and a decrease in short chain fatty acids, all leading to a pro-inflammatory gastrointestinal environment. This ongoing intestinal inflammation is of particular concern in celiac disease (CD) patients, with research showing that after implementation a GFD, the relative risk for mortality in the first year post-CD diagnosis was almost double that of total villous atrophy CD.
The authors write, “The necessity of comprehensive education for transitioning the patient to a healthy GFD, free from an emphasis on GF commercial foods high in calories and low in nutrients, cannot be overemphasized.“ In summary, if you’re already on a GFD or considering one, focus on eating nutrient-rich minimally processed foods – or as the authors suggest, adapt the Mediterranean diet, which is rich in fiber, antioxidants, anti-inflammatory compounds, vitamins, minerals, fatty acids, protein, and supports a healthy microbiome.