Repair | The Paleo Mom

How Long Does it Take the Gut to Repair after Gluten Exposure?

September 27, 2012 in FAQ, FAQ, Featured Posts, Gut Health

This is a very relevant question for those who are just embarking on their gluten-free journey. But, it’s also extremely important for anyone who has been following a paleo/primal/gluten-free diet for a while, but has been inadvertently exposed to gluten. It sometimes feels as though the longer we avoid gluten, the more sick we feel after accidentally eating some. This is in large part because the body stops protecting itself from gluten (for example, there may be less mucus in the gut) so when we do consume some, we are defenseless. It may also be because we forget how we used to feel and are so used to feeling so much healthier. Whether you are new to paleo or have been eating this way for a while, a common question is: how long does it take the gut to heal after gluten exposure?

I have talked about the irritation, inflammation and damage to the lining of the small intestine that can be caused gluten (I promise I will go back and add references to this post soon) and I have mentioned that it can take up to 6 months for the body to fully heal after a single gluten exposure. After delving into the research more thoroughly, I have discovered that this statement is simultaneously a gross understatement and an overstatement. Just like the extent of damage that gluten causes varies from individual to individual (see this post for a little bit more on variability in tolerance), so does the length of time it takes to recover. And it’s not as simple as the more damage you have, the longer it takes to recover. There are factors that control how sensitive you are (genetics, overall health, diet, stress, nutritional-deficiencies, gut microflora) and there are factors that affect how quickly you heal (okay, it’s the same list of factors, but it’s more complicated than A+B=C).

The cells that line the gut, called enterocytes or gut epithelial cells are organized into hills and valleys (to help maximize the surface area of the gut), forming finger-like columns of cells called villi separated by valleys called crypts. The enterocytes are constantly regenerating themselves (a pool or resident stem cells supplies the new enterocytes). As the cells age, they migrate higher up the villi and are eventually shed into the gut to be redigested (yes, we are constantly cannibalizing ourselves). This is called the “turnover” of the gut epithelium. In the normal healthy gut, the enterocytes migrate to the top of the villi in in 1-4 days, meaning that all of the villi cells are replaced with new cells every 3-5 days (this gets slower as we age) ^1,2,3. The cells that migrate toward the bottom of the crypts have a longer lifespan of 2-3 weeks. What does this mean? A healthy person has an entirely new intestinal lining every 2-3 weeks.

Repairing the intestine following injury (whether that is caused by ingested toxins, infection, or some other injury) is a more involved and complex process that is tightly regulated and controlled by the body (for a detailed understanding of this process, see reference 4). The healing time varies depending on the extent of injury and studies trying to understand the role of the resident stem cells of the gut show that repair of the crypt and villi structure of the intestinal wall after injury can take anywhere from 2 to 12 weeks (depending on whether the stem cells themselves are injured) in the absence of confounding factors ^4,5.

What does this mean? For healthy individuals without celiac disease or gluten sensitivity (where their bodies are producing antibodies against gluten), the damage to individual cells and the junctions between them that can be caused by gluten is relatively fast to heal, anywhere from a few days to 3 weeks. For these healthy individuals, most of this time is likely asymptomatic. Many people report symptoms that only last from a couple of hours to a couple of days after gluten exposure. This also means that healthy individuals should be able to heal their guts completely after following a 30-day paleo challenge such as a Whole30.

For those with confounding factors, healing is slower. Confounding factors are numerous and include gluten sensitivity (where the body is producing antibodies against gluten which increases inflammation and slows healing), celiac disease (an autoimmune condition), uncontrolled inflammation in the gut (which could be caused by food allergies, food sensitivities or diseases such as Inflammatory Bowel Disease), nutritional deficiencies (which can be caused by having a very inflamed and damaged gut, but slows healing because not all of the raw materials needed to repair are available), gut dysbiosis (the wrong type, amount and/or location of microorganisms in the gut), infections, stress, body-wide inflammation, and chronically elevated insulin.

How much do these confounding factors slow healing? The extreme end of the spectrum is those with Celiac Disease, an autoimmune condition triggered by gluten exposure. One hallmark of Celiac Disease is a shortening or blunting of the intestinal villi which is observed by performing a biopsy of the small intestine (they are typically 3-5 times longer in healthy individuals than those with Celiac Disease). For those with celiac disease, one study showed that only 66% of patients had a normal intestinal biopsy after 5 years on a gluten-free diet ⁶. This means that even after 5 years, 34% of Celiac Disease sufferers had not recovered. There are no good similar studies evaluating intestinal repair in people with non-celiac gluten-sensitivity, but medical professionals who specialize in treating gluten-sensitivity report time frames of approximately 1½-2 years ⁷.

It’s probably worth mentioning here that current reports suggest that both Celiac Disease and gluten-sensitivity are ridiculously underdiagnosed. It is estimated that 1 in every 100 Americans suffer from Celiac Disease but only 5% are ever diagnosed ⁸. This means that there is something like 2.5-3 million Americans with celiac disease that have no idea that they have it (when you extrapolate this statistic globally, it’s even scarier!). Gluten intolerance is estimated to affect 15-20% of the population ⁹. The take home message here? Even if you have never been diagnosed with celiac disease or gluten intolerance, you may have one of these conditions which could be contributing to slowed intestinal repair after switching to a paleo diet or after accidental gluten exposure.

How much gluten can cause a problem? This is highly individual. For those with Celiac disease (whether confirmed or undiagnosed), even a minute amount of gluten can cause significant damage to the small intestine in the majority of sufferers ¹⁰. Interestingly, a not unsubstantial percentage of these people (22%) will have significant damage to their small intestine but not suffer any gastrointestinal symptoms. For healthy individuals, the threshold amount to suffer symptoms is highly variable. Unfortunately, you don’t know until you test it on yourself.

So, how long does it take the gut to repair after gluten exposure? Once again, like so many topics I cover on this blog, the answer is “it depends”. For healthy individuals, healing likely takes only a couple of weeks. For those with celiac disease (and perhaps autoimmune diseases in general), fully healing the lining of the small intestine may take years. The rest of us can be anywhere in between.

1 Creamer B et al. “The turnover and shedding of epithelial cells–Part I The turnover in the gastro-intestinal tract”. Gut 1961 2: 110-116

2 Lipkin M et al. “Cell Proliferation Kinetics In The Gastrointestinal Tract Of Man. I. Cell Renewal In Colon And Rectum” J Clin Invest. 1963 June; 42(6): 767–776.

3 Godlewski MM et al “Into the Unknown–The Death Pathways in the Neonatal Gut Epithelium” Current Pediatric Reviews. 2011. 7(4):337-345

4 Blikslager AT et al. “Restoration of Barrier Function in Injured Intestinal Mucosa” Physiol Rev 87:545-564, 2007.

5 Booth C and Potten CS “Gut instincts: thoughts on intestinal epithelial stem cells” J Clin Invest. 2000;105(11):1493–1499.

6 Rubio-Tapia A “Mucosal recovery and mortality in adults with celiac disease after treatment with a gluten-free diet.” Am J Gastroenterol. 2010 Jun;105(6):1412-20.

7 http://glutendoctors.blogspot.com/2010/04/healing-time-after-removing-gluten.html

8 Lohi S et al. “Increasing prevalence of coeliac disease over time.” Aliment Pharmacol Ther. 2007 Nov 1;26(9):1217-25.

9 http://www.gastroendonews.com/ViewArticle.aspx?d=In%2Bthe%2BNews&d_id=187&i=October%2B2010&i_id=672&a_id=16015

10 Lähdeaho ML et al. “Small- bowel mucosal changes and antibody responses after low- and moderate-dose gluten challenge in celiac disease.” BMC Gastroenterol. 2011 Nov 24;11:129.

Tags: ancestral, celiac, crypt, damage, Diet, disease, enterocyte, epithelial, epithelium, Gluten, gut, heal, how long, inflammation, intestinal permeability, intestine, intolerance, leaky, paleo, Paleolithic, prevalence, primal, rate, Repair, sensitivity, tight junction, time, turnover, villi, villus
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TPM Tidbit: My Experiment with L-Glutamine

July 27, 2012 in Supplements, TPM Tidbits

A number of followers have pointed me toward L-glutamine supplementation as a way to reduce sugar cravings, which I experience when stressed or fatigues. As I started researching the merits of L-glutamine supplementation, I found evidence that it can also speed up healing the gut and reduce systemic inflammation, including inflammation in the brain. I have started to thoroughly research this topic for an upcoming post, as there seems to be some fairly well understood mechanisms for why a deficiency in glutamine may contribute to a leaky gut. I started supplementing with L-glutamine two weeks ago, taking 1-2g on an empty stomach between meals 2-3 times a day (I have to admit, I have not been that regular with when I take it because my life has been so hectic lately). I actually started with a lower dose, but increased to this level after reading the recommendations in Practical Paleo (how cool to read about the benefits of L-glutamine supplementation from such a reliable source just one week after I started! And as a quick aside, if you haven’t ordered this book yet, I highly recommend that you do!).

What have I noticed so far? My sleep has been fabulous. Even when my kids get me up at night, I seem to slip back into a deep sleep very easily. I have had far less muscle soreness after particularly challenging yoga classes. It does seem to help sugar cravings if I take a dose right when I’m starting to look around the house for something sweet to eat that won’t irritate my digestion too much (tough on the Autoimmune Protocol!). And, I have had higher carbohydrate meals in the last week (stress plus displacement from my home), which normally causes horrible bloating and constipation, and was absolutely fine afterward, no ill effects to my digestion whatsoever. Now, I have to admit that this experiment overlaps with my no coffee experiment. So, now I have to evaluate if any of the benefits I am seeing is actually due to my avoidance of coffee (and this is why I always advise changing one thing at a time!). My plan is to reintroduce coffee while keeping up with the L-glutamine supplements and see how I do (late next week some time I think).

Tags: ancestral, brain, craving, cravings, Diet, glutamine, gut, healing, inflammation, L-glutamine, mood, paleo, Paleolithic, primal, Repair, Sleep, Sugar, supplement, supplementation, supplements, Weight Loss
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Modifying Paleo for Small Intestinal Bacterial Overgrowth

July 3, 2012 in FAQ, Gut Health, Paleo Modifications

Small Intestinal Bacterial Overgrowth (or SIBO) is a chronic bacterial (and/or yeast) infection of the small intestine, characterized by excessive number and/or abnormal type of bacteria (and yeast) growing in a part of the gastrointestinal tract that normal contains relatively few microorganisms. These bacteria can cause a variety of problems by interfering with digestion and absorption of nutrients and by damaging the lining of the gut, causing a “leaky gut” (I addressed the many health problems that can arise from a leaky gut in this post).

The most common symptoms of bacterial overgrowth include abdominal pain, nausea, bloating, gas, belching, flatulence, chronic diarrhea, and chronic constipation. These symptoms are due to the large volume of bacteria the digestive tract (alive and dead, as they read the end of their lifecycle) and the large amount of gas and metabolic waste that they produce. Many more symptoms of SIBO are a direct effect of nutrient malabsorption. This arises either from the bacteria metabolizing those nutrients before we can absorb them or by the bacteria causing enough inflammation in the lining of the gut that it the gut can’t work properly anymore. For example, the bacteria preferentially consume iron and vitamin B12, causing anemia. The bacteria decrease fat absorption by deconjugating bile leading to deficiencies of vitamins A & D and causing steatorrhea (fatty stools). As the gut lining becomes increasingly inflamed and leaky, larger and not fully digested food particles enter the body, causing an immune reaction which leads to food allergies and food sensitivities. Bacteria themselves can enter the blood stream causing systemic inflammation and immune reactions that can lead to autoantibody formation and autoimmune diseases (for a comprehensive review article see the footnote).

SIBO was only described in the late 1990s and is still grossly underdiagnosed. This is partly because many patients don’t seek medical attention for their SIBO symptoms, because many doctors aren’t aware of its prevalence and don’t consider it in their differential diagnostics, and because the tests for SIBO still have fairly high false negative rates (where you have the disease but the test says you don’t). As SIBO becomes more recognized, it is also becoming inextricably linked with many other diseases. Many physicians and scientists now believe that Irritable Bowel Syndrome (the cause of which has never been properly defined) is actually a group of symptoms caused by SIBO (see the book The New IBS Solution). SIBO is also often associated with Crohn’s disease, Celiac disease, short bowel disease, various liver diseases, fibromyalgia, some autoimmune diseases (such as scleroderma, diabetes, lymphoma, and chronic lymphocytic leukemia and the aforementioned Crohn’s disease and Celiac Disease) and even rosacea (for a fantastic summary of confirmed related diseases, see http://www.siboinfo.com/associated-diseases.html). Whether SIBO is a causal factor or a symptom of these diseases remains to be determined. Given how new all of this science is (and how prevalent SIBO actually is!), I suspect that over the next few years many more health conditions will linked with SIBO.

How do you know if you have SIBO? If you have digestive symptoms, especially if they persist after adopting a strict paleo diet, SIBO is a possibility. You can opt to get tested (there are several different test options which can be ordered by your primary care physician), however know that the current testing methods are not 100% reliable. One of the easiest ways to determine whether you have SIBO is to see if diet modifications aimed at treating it make you feel better.

How can you fix SIBO? There are two diets (very similar to each other) that have been developed with the intention of starving the bacteria in the small intestine and healing the damaged lining of the gut. These are the GAPS (Gut and Psychology Syndrome) diet(see Gut and Psychology Syndrome) and the SCD (SpecificCarbohydrate Diet) diet (see Breaking the Vicious Cycle). The general approach to these diets is to eliminate any dietary sugars that are not monosaccharides. Monosaccharides are simple sugars like glucose and fructose and are the most easily absorbed in the digestive tract. More complex sugar molecules like sucrose (i.e., table sugar which is a disaccharide) and starches have to be broken down into monosaccharides before they can be absorbed. This means that the sugar takes longer to be digested, which means it travels farther down the digestive tract before being completely absorbed, which means that some of it reaches the abnormal bacteria growing in the small intestine and provides a food source for them. These diets also focus on consuming healing foods such as bone broth, conjugated linoleic acid found in the fats from grass-fed animals, and coconut oil. I recommend combining one of these diets with a paleo diet for the most rapid and effective reversal of SIBO.

A standard paleo diet is typically not enough to treat and reverse SIBO. Attention also needs to be paid to the amount and types of carbohydrates being consumed. I recommend following a paleo diet with modifications disallowing starchy vegetables and high sugar foods as per the SCD and GAPS diets (see my post Fruits and Starchy Vegetables with SmallIntestinal Bacterial Overgrowth). Many people may find taking Apple Cider Vinegar before meals (as outlined in TheStomach Acid Connection) is helpful. For more severe cases digestive supplements may be beneficial (I am not familiar enough with these to recommend a particular brand, type or dose. Recommendations can be found in The Paleo Solution, It Starts With Food, and this post from Chris Kresser. If you need personalized recommendations, I suggest contacting Diane Sanfilippo at www.balancedbites.com). You may also find some good information in my posts Repairing the Gut and What Should You Eat to Heal a Leaky Gut? I also want to mention that stress management is very important (see my post How Mood and Gut Health Are Linked). Homemade bone broth and a source of Vitamin D(sunshine, liver, supplement) are particularly important to promote healing. A source of diverse probiotics (from fermented foods like Sauerkraut,coconut milk kefir, or Kombucha and/or from a high quality supplement) help to restore normal gut microflora (it’s better to keep the dose of these beneficial bacteria on the low side, at least at first, since they can add to the high volume of bacteria and increase symptoms if you’re too aggressive). In extreme cases, a doctor may recommend a course of potent antibiotics followed by a gut-healing protocol (exactly what is outlined above) and probiotics. For those with symptoms indicating the early phases of autoimmune conditions (see my post You May Have an Autoimmune Disease But Don’t Know It), following the Autoimmune Protocol for the first 1-3 months may be very beneficial.

Correcting SIBO can take up to 2 years. However, you should see improvement in your symptoms fairly quickly with gradual and continuous improvement (if you don’t, it’s worthwhile considering a FODMAP sensitivity as a confounding factor, which I will be discussing in my an upcoming post). Stress, poor sleep, infections and poor diet choices can all create setbacks. It is always difficult to commit to more restrictive forms of a paleo diet (which can be tough enough as it is!). I have what I believe is a mild case of SIBO. Because I follow the Autoimmune Protocol, I rarely have issues now. However if I slip and eat a high carbohydrate food, I fairly rapidly suffer intense bloating followed by days of gas pains and constipation. It’s not fun to follow such a restrictive diet, but is it worth it!