How might we prevent the inflammation from gluten-free diets?
The Potential Harm in Unnecessary Gluten-Free Diets
Below is an approximation of this video’s audio content. To see any graphs, charts, graphics, images, and quotes to which Dr. Greger may be referring, watch the above video.
Avoiding gluten is a must for people with celiac disease, but a gluten-free diet can have negative impacts. Watch the video to find out why.
Over the last decade or so, there’s been a growing interest in the medical literature on plant-based eating, beyond just exclusionary terms like vegetarian or vegan. Previous such studies were somewhat limited because they just split people up into either vegetarian or nonvegetarian, excluding some or all animal foods––but without taking into account the quality of plant foods. Vegans could be living off of French fries, Oreos, and Coca-Cola. Enter: “Changes in Plant-Based Diet Quality and Total and Cause-Specific Mortality,” the first study to investigate the associations between changes in plant-based diet quality and subsequent risk of death.
If you look at overall plant-based diet scores, the more you increase your intake of any plant foods and decrease your intake of any animal foods, the lower your risk of death appears to fall, but that’s because people were adding healthy plant foods like fruits and vegetables. If you just look at people who ate more processed, sugary junk over time, their mortality risk goes up, the clinical implications being that increasing intake of healthy plant foods and decreasing intake of not just animal foods, but also animal crackers, could lower the future risk of premature death. Whereas just reducing the intake of carbs in general, cutting down not just refined carbs and sugars, but healthy high-carb foods like fruits and whole grains, is associated with increased overall mortality––which would correspond to years of your life being cut short, as well as the risk of dying specifically from heart disease, stroke, and cancer.
Why are whole plant foods so good for us? Much of the benefit may be mediated by our microbiome. There are all sorts of things threatening our good gut bugs, like the over-prescription of antibiotics. However, the only factor that has been empirically shown to be important is a diet low in microbiota-accessible carbohydrates––in other words, prebiotics like fiber and resistant starch, only found one place in abundance: whole plant foods. We went from high-MAC diets to Big Mac diets, and may be suffering the consequences.
Intake of dietary fiber, which is the main source of MACs in the diet, is negligibly low compared to how we evolved. Such a low-fiber diet provides insufficient food for our gut microbes, starving ourselves of all the wonderful things they produce for us. A low-fiber diet is a key driver of microbiome depletion, and this loss is implicated in the rampant increase of chronic diseases that now plague the modern world.
We evolved getting perhaps a hundred grams of fiber a day. Our gut bugs must have been in heaven. How do you get even close to that? A cup of fruit may only have about three grams, a cup of vegetables, five grams. Why so little? Because fruits and vegetables are like 80 to 90 percent water. One has to go to the drier plant foods to really scale it up––like beans, at 15 grams, or intact grains like barley, over 30 grams per cup. But many people are avoiding common grains these days, like wheat barley and rye, due to gluten. But there is a dark side of gluten-free diets.
Now, if you have a condition like celiac disease, then you absolutely have to avoid gluten, but if not, the downsides include the potential for nutritional deficiencies, like not getting enough fiber, and toxic compounds, for example, the accumulation of heavy metals in people on gluten-free diets. Those following a gluten-free diet had significantly increased blood mercury levels––more arsenic flowing through their systems. The arsenic is likely due to increased rice consumption, because rice is a major ingredient in gluten-free foods. But you can certainly choose other grains, like sorghum—that’s my favorite rice substitute. And the higher mercury may just be because people eating gluten-free diets were tending to eat more fish for some reason. But the reason that 10 out of 10 of those without celiac disease or a recognized gluten sensitivity following a gluten-free diet experienced a pro-inflammatory gastrointestinal environment is likely due to starving your microbial self, not getting enough prebiotics, not getting enough fiber because you’re avoiding grains like wheat; so, whatever diet you choose for whatever reason, make sure you’re getting enough fiber.
Please consider volunteering to help out on the site.
- Medawar E, Huhn S, Villringer A, Veronica Witte A. The effects of plant-based diets on the body and the brain: a systematic review. Transl Psychiatry. 2019;9(1):1-17.
- Baden MY, Liu G, Satija A, et al. Changes in plant-based diet quality and total and cause-specific mortality. Circulation. 2019;140(12):979-91.
- Mazidi M, Katsiki N, Mikhailidis DP, Sattar N, Banach M. Lower carbohydrate diets and all-cause and cause-specific mortality: a population-based cohort study and pooling of prospective studies. Eur Heart J. 2019;40(34):2870-9.
- Swain Ewald HA, Ewald PW. Natural selection, the microbiome, and public health. Yale J Biol Med. 2018;91(4):445-55.
- Deehan EC, Walter J. The fiber gap and the disappearing gut microbiome: implications for human nutrition. Trends Endocrinol Metab. 2016;27(5):239-42.
- Sonnenburg ED, Sonnenburg JL. The ancestral and industrialized gut microbiota and implications for human health. Nat Rev Microbiol. 2019;17(6):383-90.
- Jew S, AbuMweis SS, Jones PJH. Evolution of the human diet: linking our ancestral diet to modern functional foods as a means of chronic disease prevention. J Med Food. 2009;12(5):925-34.
- Lerner A, O’Bryan T, Matthias T. Navigating the gluten-free boom: the dark side of gluten free diet. Front Pediatr. 2019;7:414.
- Raehsler SL, Choung RS, Marietta EV, Murray JA. Accumulation of heavy metals in people on a gluten-free diet. Clin Gastroenterol Hepatol. 2018;16(2):244-51.
Motion graphics by Avo Media
Below is an approximation of this video’s audio content. To see any graphs, charts, graphics, images, and quotes to which Dr. Greger may be referring, watch the above video.
Avoiding gluten is a must for people with celiac disease, but a gluten-free diet can have negative impacts. Watch the video to find out why.
Over the last decade or so, there’s been a growing interest in the medical literature on plant-based eating, beyond just exclusionary terms like vegetarian or vegan. Previous such studies were somewhat limited because they just split people up into either vegetarian or nonvegetarian, excluding some or all animal foods––but without taking into account the quality of plant foods. Vegans could be living off of French fries, Oreos, and Coca-Cola. Enter: “Changes in Plant-Based Diet Quality and Total and Cause-Specific Mortality,” the first study to investigate the associations between changes in plant-based diet quality and subsequent risk of death.
If you look at overall plant-based diet scores, the more you increase your intake of any plant foods and decrease your intake of any animal foods, the lower your risk of death appears to fall, but that’s because people were adding healthy plant foods like fruits and vegetables. If you just look at people who ate more processed, sugary junk over time, their mortality risk goes up, the clinical implications being that increasing intake of healthy plant foods and decreasing intake of not just animal foods, but also animal crackers, could lower the future risk of premature death. Whereas just reducing the intake of carbs in general, cutting down not just refined carbs and sugars, but healthy high-carb foods like fruits and whole grains, is associated with increased overall mortality––which would correspond to years of your life being cut short, as well as the risk of dying specifically from heart disease, stroke, and cancer.
Why are whole plant foods so good for us? Much of the benefit may be mediated by our microbiome. There are all sorts of things threatening our good gut bugs, like the over-prescription of antibiotics. However, the only factor that has been empirically shown to be important is a diet low in microbiota-accessible carbohydrates––in other words, prebiotics like fiber and resistant starch, only found one place in abundance: whole plant foods. We went from high-MAC diets to Big Mac diets, and may be suffering the consequences.
Intake of dietary fiber, which is the main source of MACs in the diet, is negligibly low compared to how we evolved. Such a low-fiber diet provides insufficient food for our gut microbes, starving ourselves of all the wonderful things they produce for us. A low-fiber diet is a key driver of microbiome depletion, and this loss is implicated in the rampant increase of chronic diseases that now plague the modern world.
We evolved getting perhaps a hundred grams of fiber a day. Our gut bugs must have been in heaven. How do you get even close to that? A cup of fruit may only have about three grams, a cup of vegetables, five grams. Why so little? Because fruits and vegetables are like 80 to 90 percent water. One has to go to the drier plant foods to really scale it up––like beans, at 15 grams, or intact grains like barley, over 30 grams per cup. But many people are avoiding common grains these days, like wheat barley and rye, due to gluten. But there is a dark side of gluten-free diets.
Now, if you have a condition like celiac disease, then you absolutely have to avoid gluten, but if not, the downsides include the potential for nutritional deficiencies, like not getting enough fiber, and toxic compounds, for example, the accumulation of heavy metals in people on gluten-free diets. Those following a gluten-free diet had significantly increased blood mercury levels––more arsenic flowing through their systems. The arsenic is likely due to increased rice consumption, because rice is a major ingredient in gluten-free foods. But you can certainly choose other grains, like sorghum—that’s my favorite rice substitute. And the higher mercury may just be because people eating gluten-free diets were tending to eat more fish for some reason. But the reason that 10 out of 10 of those without celiac disease or a recognized gluten sensitivity following a gluten-free diet experienced a pro-inflammatory gastrointestinal environment is likely due to starving your microbial self, not getting enough prebiotics, not getting enough fiber because you’re avoiding grains like wheat; so, whatever diet you choose for whatever reason, make sure you’re getting enough fiber.
Please consider volunteering to help out on the site.
- Medawar E, Huhn S, Villringer A, Veronica Witte A. The effects of plant-based diets on the body and the brain: a systematic review. Transl Psychiatry. 2019;9(1):1-17.
- Baden MY, Liu G, Satija A, et al. Changes in plant-based diet quality and total and cause-specific mortality. Circulation. 2019;140(12):979-91.
- Mazidi M, Katsiki N, Mikhailidis DP, Sattar N, Banach M. Lower carbohydrate diets and all-cause and cause-specific mortality: a population-based cohort study and pooling of prospective studies. Eur Heart J. 2019;40(34):2870-9.
- Swain Ewald HA, Ewald PW. Natural selection, the microbiome, and public health. Yale J Biol Med. 2018;91(4):445-55.
- Deehan EC, Walter J. The fiber gap and the disappearing gut microbiome: implications for human nutrition. Trends Endocrinol Metab. 2016;27(5):239-42.
- Sonnenburg ED, Sonnenburg JL. The ancestral and industrialized gut microbiota and implications for human health. Nat Rev Microbiol. 2019;17(6):383-90.
- Jew S, AbuMweis SS, Jones PJH. Evolution of the human diet: linking our ancestral diet to modern functional foods as a means of chronic disease prevention. J Med Food. 2009;12(5):925-34.
- Lerner A, O’Bryan T, Matthias T. Navigating the gluten-free boom: the dark side of gluten free diet. Front Pediatr. 2019;7:414.
- Raehsler SL, Choung RS, Marietta EV, Murray JA. Accumulation of heavy metals in people on a gluten-free diet. Clin Gastroenterol Hepatol. 2018;16(2):244-51.
Motion graphics by Avo Media
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The Potential Harm in Unnecessary Gluten-Free Diets
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Content URLDoctor's Note
Who would benefit from a gluten-free diet? See my video series on gluten:
- Is Gluten Sensitivity Real?
- Gluten-Free Diets: Separating the Wheat from the Chat
- How to Diagnose Gluten Intolerance
There’s no reason you can’t keep your good bugs happy on a gluten-free diet. There are all sorts of gluten-free intact grains that are packed with fiber. To learn more, check out:
- Which Is a Better Breakfast: Cereal or Oatmeal?
- Benefits of Quinoa for Lowering Triglycerides
- Is Sorghum a Healthy Grain?
- Studies on Millet Nutrition: Is It a Healthy Grain?
- The Benefits of Millet for Diabetes
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