Marks Daily Apple
Serving up health and fitness insights (daily, of course) with a side of irreverence.
6 May

A Primal Primer: Leaky Gut

Small IntestineAfter I mentioned it in last week’s 10 Principles of Primal Living (Finally) Getting Mainstream Media Coverage post, several readers emailed asking about leaky gut. What is it? How do I know if I have it? Why should I care if I have it? What do I do if I have it? And so on. Turns out many and maybe most people have but a vague idea of what leaky gut actually means.

Today, I’m going to fix that.

In most popular conceptions of human physiology, the gut exists primarily as a passive conduit along which food travels and breaks down for digestion and absorption. It’s where bacteria hang out and digestive enzymes go to work. It’s a “place,” an inert tunnel made of flesh and mucus. Lots of things happen there but the gut itself isn’t doing much.

Except that the gut serves another very important and active role: as a dynamic, selective barrier between us and the external world with all its nasties. Dynamic in that it responds differently depending on what’s trying to get through. Selective in that it’s supposed to let in good things and keep out harmful things.

Lining the gut are epithelial cells whose cell membranes fuse together to form protein complexes called tight junctions. The tight junction is the doorman. These are the dynamic, selective parts of the gut. Like the doorman, the tight junction’s job is to discern between what belongs inside and what doesn’t. What gets passage through the gut lining into our body and what is denied. Tight junctions keep out pathogens, antigens, and toxins while admitting nutrients and water.

That’s in a perfect world, though. Sometimes the doorman shows up to work drunk. Sometimes the doorman can’t turn down the $100 bill enfolded in a handshake. Sometimes the doorman lets the pretty girl and all her friends cut in line. Many variables can affect the doorman’s ability to discern between who belongs and who doesn’t. And the same goes for intestinal tight junctions.

How do you know if you have leaky gut?

Everyone’s gut is a little leaky, a little permissive if not downright permeable.

One way is to take an intestinal permeability test. You drink a solution containing a pre-measured amount of mannitol and lactulose, two indigestible sugars. You collect your urine over the next 6 hours and measure the amount of excreted mannitol and lactulose to determine how much permeated through your gut.

Another way is to measure levels of blood zonulin, a reliable marker of intestinal permeability. You might have trouble convincing your doctor to order this one.

You can also look at the list of conditions commonly associated with elevated intestinal permeability. If you have any or all of them, you may have leaky gut. Put another way, if you have leaky gut, you may be at a greater risk for some of these. What are they?

Celiac disease: When gluten is broken up into fragments in the gut, those fragments induce the release of zonulin, which tells the tight junctions to become more permeable. This happens to everyone whose guts come into contact with those gluten fragments, but the effect is enhanced in people with celiac. Their gluten-induced leaky gut is way more leaky than it should be, and it stays leaky long after the gluten has been gone. In fact, before direct testing for gluten antibodies and intestinal damage became widespread, a common test for celiac used to be the very same intestinal permeability assessment I just mentioned.

Inflammatory bowel disease (IBD): Patients with Crohn’s disease, an inflammatory bowel disease characterized by severe inflammation of the gut lining, tend to have leaky gut. And in general IBD, which includes Crohn’s and ulcerative colitis, high intestinal permeability precedes the development of the disease.

Irritable bowel syndrome (IBS): As discussed yesterday, IBS patients often show increased gut permeability. Some researchers suggest that leaky gut leads to the kind of chronic, low-level inflammation that characterizes IBS.

Asthma: There is a high prevalence of leaky gut in people with moderate to severe asthma, though researchers aren’t sure whether it’s a cause or consequence of the asthma.

Food allergies and intolerances: The transportation of the food allergen across the gut lining appears to be a necessary step in the development of a food allergy, and a 2011 review concluded that an overly leaky gut facilitates this transportation and leads to the inducement of allergy.

Autism: Children with autism and their first-degree relatives tend to have abnormal gut permeability, suggesting a gene-environment component to autism. This is present in some, but not all people with autism.

Rheumatoid arthritis, ankylosing spondylitis, and other autoimmune diseases: Both RA and AS have been linked to leaky gut, and the connection may hold for other autoimmune diseases, too.

Obesity and metabolic syndrome: Both obesity and metabolic syndrome are often linked with intestinal permeability, and a recent paper explores all the potential mechanisms that might explain the link.

Depression: By some accounts, 35% of depressed patients have leaky gut.

Eczema: Going back as far as 1986, researchers have found leaky gut to be common in eczema patients.

Interesting, huh? Leaky gut really gets around. It may not be the whole story, and some of these connections may be coincidental, but plausible mechanisms exist for most of them and I’m confident that fixing leaky gut will improve many seemingly disparate health problems.

Plus, even if it wasn’t the proximate cause of your health problems, leaky gut probably isn’t helping you get better and you should try to fix it. Multiple feedback loops which make teasing apart cause and effect nearly impossible also make it possible to step in the middle of the loop(s) and break it up.

Leaky gut: what it is, how to know if you have it, and what to do about it:

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What should you do?

First, avoid things that might cause it.

Gluten. Gluten begets gliadin releases zonulin induces leaky gut. I discussed this in the celiac section above, but it’s important to reiterate that gliadin has this leaky effect on every gut, not just in celiacs. Celiacs just get it worse than non-celiacs.

Stress. Stress can directly induce leaky gut (PDF) and stress can take many forms, as we all know. Bad finances, marital strife, unemployment, too much exercise, lack of sleep, extended combat training, and chronic under-eating all qualify as significant stressors with the potential to cause leaky gut, especially chronically and in concert.

Too much alcohol. Ethanol increases intestinal permeability by changing the gene expression of the proteins involved in tight junction function. If you do drink, be sure to follow best practices and definitely do not drink on an empty stomach. Alcohol also depletes zinc, which is a crucial pro-gut nutrient.

Poor sleep habits. In one recent study, mice whose circadian rhythms were disrupted were more susceptible to liver damage and alcohol-induced intestinal permeability.

NSAIDs. Non-steroidal anti-inflammatory drugs like aspirin and ibuprofen can be helpful in certain situations, but they are far from benign. One of their worst and most pronounced effects is leaky gut.

Then, take proactive steps to improve gut barrier function.

Take whey protein isolate and glutamine. Both supplements have been shown to reduce leaky gut in patients with Crohn’s disease.

Try resistant starch and other prebiotics. Whether potato starch, green bananas/plantains, mung bean starch, inulin powder, jersualem artichokes, leeks, pectin, or apples, start eating RS and other prebiotics on a regular basis. They increase butyrate production (which reduces intestinal permeability) and support the growth and maintenance of healthy microbial populations.

Take probiotics and/or (preferably “and”) eat fermented food. Prebiotics are important, but you also need to provide the right gut bugs if you’re deficient. You can do it with both supplements and food. L. rhamnosus and L. reuteri supplements reduce leaky gut and improve symptoms in kids with atopic dermatitis. L. rhamnosus also helps restore the gut barrier in kids with acute gastroenteritis. In rats with leaky gut, yogurt improves gut barrier function.

Get adequate sunlight and/or take vitamin D3 supplements. Vitamin D helps protect against injuries to the intestinal lining, while a vitamin D deficiency promotes intestinal permeability and inflammation.

Get enough zinc. Oysters, red meat, supplements – zinc supplementation reduces leaky gut.

Make broth, eat gelatinous cuts of meat. I don’t have any scientific references for this one, but it’s such a staple piece of advice in the “healing your gut” scene that it’s worth including. Plus, oxtails are magic, and science can’t quite explain magic just yet.

Exercise intelligentlyIntense, protracted exercise induces leaky gut. This is normally transient and totally manageable, but if taken to the extreme as in chronic cardio, exercise-induced leaky gut can become a chronic condition. The same goes for any kind of chronic exercise. Even too much strength training can probably do it, though you’d have to do a ton of volume without much rest. Meanwhile, moderate exercise improves gut barrier function. The tried and true triumvirate of lifting heavy things, walking lots, and sprinting occasionally is the safest bet.

Check out a free Solving Leaky Gut webinar this Thursday. If you want to hear direct from the experts who’ve helped patients solve and cure leaky gut and many of the aforementioned health issues related to it, you’ll want to attend the webinar this Thursday, May 8 at 9 PM Eastern. It’s part of a larger package called Solving Leaky Gut that gets way deeper into the condition and offers specific, proven tips, tricks, and strategies for improving your gut function, reducing food intolerances, and boosting immune health.

If all this stuff seems daunting and far-reaching, that’s because it is daunting and far-reaching. The gut affects nearly everything. But look at the bright side: fixing your gut may be the key to good health for many of you. It’s actually quite empowering. Don’t you think?

Thanks for reading, everyone!

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Imagine you’re George Clooney. Take a moment to admire your grooming and wit. Okay, now imagine someone walks up to you and asks, “What’s your name?” You say, “I’m George Clooney.” Or maybe you say, “I’m the Clooninator!” You don’t say “I’m George of George Clooney Sells Movies Blog” and you certainly don’t say, “I’m Clooney Weight Loss Plan”. So while spam is technically meat, it ain’t anywhere near Primal. Please nickname yourself something your friends would call you.

  1. I don’t have intestines. Just a sieve.

    Groktimus Primal wrote on May 6th, 2014
  2. Well, according to this, gluten is best avoided in general, even in people who are not celiacs.

    Since I cut wheat out of my diet I’ve found that when I do indulge in donuts or beer my gut isn’t happy. And recently I’ve found that beer and sweet pastries just don’t have the allure that they used to have. Personally I think that’s my gut shaping my decisions.

    C L Deards wrote on May 6th, 2014
    • Samesies!

      Vince G wrote on May 6th, 2014
    • “Well, according to this, gluten is best avoided in general,even in people who are not celiacs.”
      That sure appears to be the intended implication, considering the way things are phrased – which seems biased to me, though:
      Gluten has a “leaky effect on every gut” (reiterated and heavily emphasized), ergo: avoid gluten (“blanket deduction”).
      Alcohol “increases intestinal permeability” (translation: same thing really – but this time the wording is more abstract, and there is no particular emphasis on the fact that “no one is safe,” which results in a comparatively negligible “visceral impact factor” of the statement),
      ergo: avoid too much alcohol (nuanced deduction applying more of a “global” perspective).
      Am I the only one who sees a double standard here?
      (In my opinion, the fact that gluten-containing grains are a part of the diet in several of the “Blue Zones” – i.e., are eaten by some of the longest-lived healthy populations we know of – as well as several “Mediterranean Diet” intervention trials indicate that the “aggregate impact” of gluten consumption may be (relatively) benign (for at least some people), depending on dose and context – just as epidemiology indicates that the “aggregate impact” of alcohol consumption can be (relatively) benign (for at least some people), depending on dose and context.)

      Karl wrote on May 7th, 2014
      • IMOH, Mark addresses wheat and gluten well. Don’t Americans consume excessive ammounts of wheat when compared to the Mediterranean cultures? Rice is something most people I know TYPICALLY AVOID. Personally, since I need the starch, replacing bread with rice has helped me so much!

        j wrote on May 7th, 2014
        • Do Americans “consume excessive ammounts (sic) of wheat” at the expense of other foods, on average? Probably. That is, however, irrelevant with regard to the point I was trying to make, namely that the chain of argumentation this article presents is inconsistent: If one reasons that nutritional components which have “a leaky effect on every gut” should be avoided completely, it follows that both gluten and alcohol are strictly verboten; conversely, if one stars out from more of a “bird`s eye perspective,” thus arguing that hitting the sauce can be A-okay depending on dose/context/individual circumstances because there is more to alcohol consumption than just its effect on intestinal permeability, the same goes for gluten-containing foods – ergo: Don`t eat too much gluten, don`t drink too much alcohol. See what I mean?

          Karl wrote on May 8th, 2014
        • “…if one starts out from…”

          Karl wrote on May 8th, 2014
      • Quote from Karl “In my opinion, the fact that gluten-containing grains are a part of the diet in several of the “Blue Zones” – i.e., are eaten by some of the longest-lived healthy populations we know of – as well as several “Mediterranean Diet” intervention trials indicate that the “aggregate impact” of gluten consumption may be (relatively) benign (for at least some people), depending on dose and context”

        It could also be a genetic thing.

        Christine wrote on May 8th, 2014
        • Sure it could (although the Bayesian probability appears low, considering, among other things, a)how widely scattered the respective “Blue Zone”-populations are geographically – unless one were to invoke convergent evolution, which would in turn undermine the basic “Paleo premise” -, and b) that there are Mediterranean diet intervention trials including gluten-containing grains which document net health improvement ); correlation does not equal causation, yadda yadda yadda. My main point is that exactly the same goes for the epidemiological data implying that moderate alcohol consumption can be part of a healthy nutritional pattern, or even improve on it – so why not also declare drinking alcohol strictly verboten on the grounds of it demonstrably having “a leaky effect on every gut” (directly and indirectly, considering that beyond its immediate effects on intestinal permeability it also disrupts one`s sleep quality, which – gasp!- worsens “leaky gut,” as the stellar example of impartial science journalism we are discussing here informs us) – never mind those moderate drinkers who seem to do just fine; after all, it “could… be a genetic thing” .

          Karl wrote on May 8th, 2014
        • Americans eat too much bleached gluten. It’s the bleach that causes the problem because it kills beneficial bacteria while feeding candida. Candida is the real reason for leaky gut and everything about wheat feeds candida so people have in their minds that wheat is the problem. It’s not, it’s just a symptom.

          In ancient times, even as late as 200 years ago the only, “yeast,” bread that anyone ate was sourdough. For thousands of years this was the case. So the bread had lactobacilius bacteria in it. And I read in the bible they used to dip it in wine vinegar, which had to have had the mother still in it which meant even more lactobacilius bacteria in every bite.

          It’s not that we eat wheat, it’s the way we eat it.

          Dean Ellis wrote on June 10th, 2014
    • Same here…. ive been doing alot of testing on my self… the gluten protein looks like the yeast protein.. you may find you also feel better eating less corn, potato etc as these feed yeast.. you find most gluten free people switch to these flours yet never get better but feel better not eating gluten

      eddie wrote on May 8th, 2014
      • It’s because they are only treating the symptom. Gluten intolerance is a symptom of a larger problem. That problem is candida overgrowth. Fix the candida overgrowth and they will be cured and then able to once again eat gluten.

        Most people who cut out gluten actually increase their sugar intake to improve flavor which makes the candida problem worse. It’s why they still feel bad if they eat gluten. The candida is still there. Fix the candida the the gluten intolerance goes away.

        I’m living proof of this.

        Dean Ellis wrote on June 10th, 2014
        • Hi Dean, can you please leave another post and tell me what you did to get rid of your yeast overgrowth and how long it took? Thanks so much

          Linda wrote on January 1st, 2016
        • And I am living proof that you can have gluten intolerance and NOT because it’s a symptom of candida. I was simultaneously tested for both. I also eat no sugar even though I eat no grains. So while in some instances your experience is true, it’s not the case for all.

          My gluten intolerance is not a symptom of a larger problem, it’s a DNA flaw (it’s on my genome) and I will never be able to eat gluten without consequences, unless I find a way to turn off that gene expressing itself.

          Carrie wrote on August 13th, 2016
  3. Good stuff, Mark. As mentioned recently, I think this is the best subject (gut health) you’ve undertaken. Without gut health, we’re basically bailing out a sinking ship; with it, we’re well on the way to optimal overall health.

    Bear wrote on May 6th, 2014
    • +1

      j wrote on May 7th, 2014
  4. The info on that intestinal permeability test being a ‘common’ way to diagnosis celiac is wrong – the article linked to is from 2000 – newer, more accurate tests are available and have been for years. The gold-standard for diagnosing celiac is a blood test to look at gluten antibodies, followed by an intestinal biopsy to confirm and assess damage. The intestinal permeability test won’t tell you if you have celiac- just if your gut is especially permeable or not.

    Otherwise, very interesting!

    Kate wrote on May 6th, 2014
    • The paper in question suggests the use of lactulose and manitol as a screening test for celiac. However, there are direct antibody test available in the 21st century, so why bother? Also there aren’t any validated and commercially available tests for zonulin level, so even if you could convince your poor doctor to order the test, there wouldn’t be anything to order. Plus it appears that the half life of zonulin is pretty brief, so getting a good level, if there were a test, would be a bear.

      Abijah L. wrote on May 6th, 2014
      • There is a test called Array 2 or Intestinal Permeability Screen from Cyrex Labs. The screen tests for, Actomyosin IgA, this tells if the leak is through the cell itself. Occludin/ Zonulin IgG, IgA, and IgM, this tells if it’s through the tight junctions. The last three are Lipopolysaccharides (LPS) IgG, IgA, and IgM which refer to time, endotoxins found in bacteria etc. There is also a test called Array 4 or Gluten Associated Cross-Reactive Foods and Foods Sensitivity. There are 5 cross reactive foods to gluten, the others are sensitivities.
        I’ve seen plenty of these tests. Not everyone has noticeable symptoms for intestinal permeability, or doesn’t know or have a practitioner that knows what diseases or auto immune conditions are signs. For that matter, there is also a Blood Brain Barrier Permeability test. One of my favorites is Array 5 for Multi Auto Immune Reactivity Screen. This one shows about 24 antibodies to tissues in the body, adrenals, arteries, Gad65, insulin, osteocytes, cytochrome P 450,etc..
        All the best.

        Darlene wrote on May 7th, 2014
  5. I don’t think I have a leaky gut but I’ve been primal for 4 years. I have so many close family members that think it is normal to have some of these issues. It isn’t normal at all! Why can’t more people see that? Are we becoming so used to being sick and tired that sick and tired is the norm?

    My niece is high functioning autistic. What is the harm in trying to change diet? My mom has severe arthritis, why not give 30 days to get relief? oh wait she did, and felt like a million bucks. But then old habits creep back in and the mind wants to forget what feeling good really feels like.

    I’m over the laziness. Things will only get worse until we stop and make a change.

    NOLA Paleo (new orleans) wrote on May 6th, 2014
    • I am right there with you in frustration. I see many family members with issues that could be improved or solved with a change to diet (as I have done for myself), but they don’t want to hear it or give it a try. I don’t think they realize how bad “normal” feels to them, or, like you said, they don’t want to give up old habits. I wish I had a solution! I hate seeing them suffer! (Yet when they complain about feeling sick, and declare that it doesn’t make any sense, since they “do everything right,” it REALLY frustrates me!)

      Brooke wrote on May 8th, 2014
      • Some people resist change. They just don’t want to because it stresses them out to think about the effort it would take for them to do it. I have family that are the same way, they’d rather complain than do something about it. But that doesn’t mean I won’t keep making the same suggestions, cause I think eventually they’ll try them.

        Benjamin Thomas wrote on May 8th, 2014
  6. watch out for anti-biotics as well as over exercising, stress, alcohol etc
    I think the best fermented foods are kimchi, sauerkraut and unflavored yogurt. Probably best to steer clear of those fruit bottomed, colorful packaged little yogurts that are more sugar and corn starch than beneficial yogurt.

    jamie wrote on May 6th, 2014
  7. Here’s how a leaky gut and food allergies set off my rheumatoid arthritis: the food I’m allergic to is seen as toxic. The toxins enter my bloodstream (largely undigested) through my leaky gut. The bloodstream carries those toxins to all my muscles and joints, causing debilitating pain, stiffness, and inflammation–to the point where I can hardly move at all. 4 days in bed and tons of Benadryl later, I’m better, but not back to normal–that takes another day.

    I used to endure this on a daily basis when I was 3, only no Benadryl to fall back on. I wish I knew back then about the food allergy aspect of it. Today, when it happens, I know why and what to do about it. I limit it happening by being aware of food ingredients. If i get a nasty surprise, out comes the Benadryl right away.

    Wenchypoo wrote on May 6th, 2014
    • What does the benadryl do for you? Stop allergic response?

      brandie wrote on May 6th, 2014
  8. ‘You collect your urine over the next 6 hours and measure the amount of excreted mannitol and lactulose to determine how much permeated through your gut.’

    Going on this test, does this mean that people with leaky gut are excreting more vitamins / nutrients through their urine? I ask because when I eat liver, my urine turns a freakish fluorescent yellow. Is this normal, or is this a symptom of leaky gut through Vitamin A malabsorption?

    Josh wrote on May 6th, 2014
    • Super yellow pee usually caused by excreting B vitamins. This is common in everyone. I take a B complex daily because of previous fatigue issues, and I notice when I am feeling fatigued everything is fine on the pee front, but when I feel normal and upbeat etc my pee is bright yellow from 2-4 hours after I take the supplement. I drink 3L+ of water a day so I know it’s not that. Liver is super high in Bs so it’s likely your body is just getting rid of the vitamins you don’t need!

      Krissy wrote on May 6th, 2014
      • Thanks Krissy – that makes sense!

        Josh wrote on May 6th, 2014
  9. Mark, thanks for the Gut Check.

    Nocona wrote on May 6th, 2014
  10. A lot to consider…and I continue to be confused by the idea of “chronic cardio”…I love running distances, but at a very manageable pace and I wonder what effect that has if any? It’s obviously individual to some degree but since it keeps coming up (at least on this website) I wonder if there is any way to actually tell if you have crossed over into chronic cardio beyond moderate exercise.

    Michele wrote on May 6th, 2014
    • Elevated cortisol levels,oxidative stress,and free radical production are things you could get tested but I have a couple of sisters who run all the time who used to be “strong looking” with those famous curves men tend to be especially fond of. Now they look like Demi Moore. You don’t want to look like Demi Moore.

      victor wrote on May 6th, 2014
      • Aaah, unbiased, evidence-based recommendations – you just gotta love them.

        Battousai wrote on May 7th, 2014
      • Not sure I remember the Demi Moore section of Mark’s book :)

        Michele wrote on May 7th, 2014
        • Anyway I linked over?! to your sight and you definitely look healthier than Demi Moore. Do you do any resistance training? When you do anything at a “comfortable” level you’re inviting muscle atrophy into the picture over time. Also replacing a 10 mile run for a half hour weight lifting session just one day a week will help your race times.

          victor wrote on May 7th, 2014
    • My thinking is – if you are still feeling soreness from your last run, wait another day to run again. This applies to any exercise.

      John Es wrote on May 6th, 2014
      • Sorry, my response wasn’t very thoughtful. Your cardio recovery might be hard to measure using soreness. Maybe declining performance would be an indicator? Take an extra day of rest and see if performance is better?

        Obviously, I’m not too worried about my lazy ass doing any chronic level of exercise!

        John Es wrote on May 6th, 2014
        • Ha! Even when I caught myself clearly overtraining I wasn’t sore, running has other sneaky ways of catching up on a person though.

          Michele wrote on May 7th, 2014
    • Michele,

      your confusion is warranted, seeing as the whole “chronic cardio”-conundrum is actually based on an extremely vague concept, as far as I can tell: It emphatically declares that “too much endurance exercise is bad for you,” but doesn`t offer a reliable definition of “too much”: Some proponents are convinced that any mile you run is one too many – that is demonstrably BS, as mountains of data demonstrate; others are more moderate, and content themselves with recommending no more than approximately 20 miles of weekly running (James O`Keefe is a relatively well-known representative of this subgroup) – the evidence base for this recommendation, however, is the next best thing to nonexistent at this point, too. If one goes by the consensus of most reasonable exercise physiologists, there may very well be such a thing as “too much running” – but there are currently no reliable data that adequately define the training volume at which “Average Joe/Jane” enters the “danger zone” (A recent “Sweat Science”-article by Alex Hutchinson provides a decent summary on the topic:”Will Running Too Much Kill You?The annual look at the current state of the evidence.”).
      If we go by Mark`s utterances on the matter, you probably don`t need to worry, considering that you run “at a very manageable pace”: According to “The Definitive Guide to Low Level Aerobic Activity,” moderate exercise “involves working at 55 to 75 percent of your maximum heart rate,” the upper limit of which is likely to correspond to “a medium cardio workout at the gym” for “a fit person” (ironically, this definition probably encompasses the bulk of the training of most contemporary professional endurance athletes, too). Apart from that guideline, your best bet would probably be to pay attention to your heart rate variability (HRV) with a decent cardiotachometer, seeing as frequent blood tests (in order to document the development of your inflammatory markers) are a real pain in the butt.

      Battousai wrote on May 7th, 2014
      • Thanks so much for the detailed response. I will check out that article as well as a hrm. Frequent blood tests definitely would not work for me.

        Michele wrote on May 7th, 2014
    • Michele,

      I don`t think you need to worry, considering your “very manageable pace”: If we go by Mark`s own definition in his “Definitive Guide to Low Level Aerobic Activity,” moderate exercise “involves working at 55 to75 percent of your maximum heart rate,” the upper limit of which corresponds to “a medium cardio workout at the gym” for “a fit person” (and, somewhat ironically, encompasses the bulk of the training regimen most contemporary endurance athletes adhere to – not to mention that the whole “chronic cardio” concept is a rather dubious hypothesis at this point, anyway – take a look at “Will Running Too Much Kill You?” by Alex Hutchinson).
      In addition to the mentioned guideline, you might start paying attention to/tracking your heart rate variability – not only does it appear to be a useful diagnostic tool, it is also decidedly less of a pain in the butt than getting (monthly?weekly?daily?) blood tests in order to check up on your inflammatory markers.

      Karl wrote on May 7th, 2014
      • Thanks…this has pretty much been my thinking. A heart rate monitor is definitely something I’ve considered as an all around useful tool for training and may take the plunge to remove a lot of guess work. Thanks for the input :)

        Michele wrote on May 7th, 2014
  11. Mark

    Just curious as to why doctors will hesitate to order the test that measures zonulin levels?

    Someone above mentioned the other test was out dated?

    Luke wrote on May 6th, 2014
  12. A thought: if 35% of people with leaky gut are depressed, and extended combat training can worsen symptoms…I wonder if leaky gut and PTSD share a link, then, too…

    Kevin Grokman wrote on May 6th, 2014
    • I’ve GOT to shout out about this book: “Waking the Tiger: Healing Trauma” by Peter A. Levine (which is followed by: “In an Unspoken Voice: How the Body Releases Trauma and Restores Goodness” by Peter Levine). O.M.G.!! I feel like these two books are the holy grail of understanding and treating PTSD!! I know he’s working with the VA — but I wish every military person — PTSD or not — could read either or both of these! (And every OTHER person who has ever had any trauma…) Talk about understanding ‘primal’ therapy for trauma! Talk about working with the primal self (our kinda primal, in this field) to return to health. (A total epiphany when I read it the first time!)

      (And a grateful tip of my hat, if I wore one, to Dr. Gabor Mate’ — who wrote the forward to “Unspoken Voice,” and who is just brilliant about ADHD/ADD, which he describes in his book(s) as biological but not genetic. I hope that piques some interest, as his stuff is marvelous too!)

      Elenor wrote on May 6th, 2014
      • Funny: I have ADD. And with the link to PTSD and depression in general, I thought for the first time, earlier today after reading this article, if ADD could also potentially be influenced by diet!

        Kevin Grokman wrote on May 6th, 2014
        • Kevin — try Gabor Mate”s book called “Scattered” — fascinating! He was diagnosed with ADD in his early ’50s, as were two of his kids at the same time. (I think, in the U.S., the publisher called it “Scattered Minds” (to Mate”s dismay), but the U.S. paperback is called just “Scattered.”

          There are also some amazing YouTubes of talks by both Mate’ and Levine. SO worth your time!!

          Elenor wrote on May 6th, 2014
        • I’ll make a note of it! I am currently reading ADD-Friendly Ways to Organize Your Life and have another on hold: You Mean I’m Not Lazy, Stupid, or Crazy?! I’ll have to add Scattered! Thanks! :)

          Kevin Grokman wrote on May 6th, 2014
      • Thanks for the tip on these books! As a veteran, I have been mulling over how switching over to this lifestyle might affect my PTSD. Changing foods is pretty easy for me with the latest step being to take out coffee (because I require sugar with it) and switch to a mate’ (Teavana has great tea)

        My issue is SLEEP. Eustress and distress cause me to wake at 0 dark 30 way too often. I could take two benadryl every night but really,….I’m syper afraid of drugs.

        Any suggestions would be appreciated.

        Charlotte wrote on May 8th, 2014
        • Charlotte — is your oh-dark-thirty usually right around 3 a.m.? Please look into adrenal fatigue! I used to wake up every night right at 3:18 (and no, none of my neighbors had an alarm clock set for then or anything…)

          Once I researched the heck out of adrenal and thyroid dysfunction/insufficiency and actually treated them (and yah absolutely hafta fix the adrenals first or any thyroid fix won’t ‘take’!), I stopped waking bolt-awake in the middle of the night. (It has to do with the two glands being (way!) less-than-optimal, and when your hormone levels drop too low — right around 3 a.m. — your adrenals send you a lovely (NOT!) shot of adrenaline. YIKES!) Mark has great info, although I benefited most from the website Stop the Thyroid Madness — Janie (Bowthorpe) really knows this stuff!

          In the meantime — get some Himalaya salt, and take a teaspoon every morning to support your adrenals! Some folks mix it was orange juice ({gag!} and I don’t drink juice anyway) — I found microwaving it (and I worked up to a TBL) in about 1/3 C water (to get the salt into suspension) and then cooling it with a couple of ice cubes allowed me to chug it like a shot. {shudder} Always, always follow with a huge glass of clear water — salt water is used as an emetic! Really helped with my adrenals.

          (I did end up going on physiological doses (which are WAY less than treatment doses, so without the horrid side effects!) of hydrocortisone — and it took me about 3 years on HC for my adrenals to recover! (Periodically, I’d try to wean off — and the adrenal symptoms came back, so, I’d go back to sea salt, HC, and waiting!) (Colloquially: The HC support allows the adrenals to “sleep and heal.”)

          OH! The amazing difference over time! I used to be wildly hypersensitive to light and noise — I told my husband to think of me every morning as *badly hung over* — no noise, no light, till after coffee. (Coffee, which whips the adrenals to work even when they’re shot!) {eye roll}

          Elenor wrote on May 8th, 2014
  13. I’ve read that there is a direct connection between vitiligo and the thyroid. However, because vitiligo is skin related and an auto-immune disorder, is there any connection between leaky guy and vitiligo? The Internets, unfortunately ;), is lacking in the information department as it relates to vitiligo.

    Lee R. wrote on May 6th, 2014
  14. Excellent article Mark! Diarrhoea and vomiting bugs can also cause temp leaky gut and will often lead to lactose intolerance although usually transient.

    Colostrum is probably the best treatment available and will not only trigger genes in your gut to start a repair job but also improve gut bacterial balance at the same time. Dr Andrew Keech is a world expert in this area and has a book that’s well worth a look. “Peptideimmunotherapy”.

    Gut integrity is so important to your immune system balance, which is why I ask myself, “if you knew the evidence against gluten why would you in your right mind continue to consume it?” Gluten free is in no way shape or form a fad it is simply essential for a viable immune system. If you want to increase your risk of allergies and autoimmune diseases you continue to throw your gut wide open by consuming modern wheat with its greatly increased gluten content. I rest my case.

    GE wrote on May 6th, 2014
    • But can the old-skool Paleo crowd hear that raw cow colostrum heals? They are so invested in hating dairy…

      Whatever wrote on May 6th, 2014
  15. Mark, thank you.

    I can personally attest to the power of gut-healing diets. My son was diagnosed with Autism at 3.5 years of age and was non-verbal. Within a week of changing his diet, he was talking in full sentences and all of his sensory processing disorders were resolved within 6 months. He is now a typical, happy, confident, and highly intelligent 6 year old kid. I, too, went on the same diet and have completely healed from chronic fatigue, cystic acne, migraines, cysts in my breasts and multiple food allergies.

    It is wonderful to see this message being shared in terms that are so practical and easy to understand.

    Shannon wrote on May 6th, 2014
    • That’s an incredible story, Shannon. Congratulations on solving these problems. Was it wheat that caused all of them?

      HB wrote on May 7th, 2014
      • Thanks HB. I suspect that it was gluten that was causing the most grief for my son. The leaky gut was allowing gluten into his bloodstream, which was causing neuro-inflammation when it hit his brain. No gluten = no inflammation = full cognitive function restored! Now that we’ve healed his gut, he can eat gluten without ill effect. He is a completely different kid. Thanks for your interest and positive feedback. Shannon

        Shannon wrote on May 7th, 2014
  16. I had a small patch of skin rash near my ankle for at least a year. Various skin cremes had little effect. After eating Paleo for a little while, I realized it healed. I’m assuming it was autoimmunity from leaky gut. I have other symptoms of autoimmunity, and they serve as reminders of how well I am taking care of my gut. No testing needed.

    John Es wrote on May 6th, 2014
  17. TMI – but when I eat primal or at least no sugars no grains (Vinnie Tortorich) no farting. That’s gotta be a winner right there.

    Jo Baxas wrote on May 6th, 2014
    • Winner or loser, depending on your sense of humor ;]

      Jessica wrote on May 7th, 2014
  18. Bovine colostrum works very best, even better than L Glutamine for healing a leaky inflamed gut. Immune Tree colostrum and Surthrival colostrum are quality colostrums. Pricy but worth it. Avoiding too much insoluble fiber is a good idea as well. Too much insoluble(undigestible) fiber irritates the walls of the intestines. This is why people eating a high “heart healthy” whole grain diet often suffer from bloating, gas, intestinal cramps, IBS, chron’s disease. Bone broths are great gor gut health as the gelatin helps repair ligaments, joints, muscles.

    Gio wrote on May 7th, 2014
    • Gio, good info! I like the tie in with “heart healthy” whole grains. Nasty stuff really. Unfortunately wheat is in reality “Big Wheat” and will probably stay “healthy” for some time.

      victor wrote on May 7th, 2014
  19. I have had problems for 40 years, going Primal 4-5 years ago definitely helped a lot but didn’t cure me.
    I tried loads of things without any result.
    And then I read an article about Leaky Gut and that Oregano Oil is very good for repairing the Leaky Gut.
    After 2 weeks of High quality Organic Oregano Oil, 6 drops twice a day, my problems are GONE.
    40 years of problems GONE in 2 weeks, a miracle.
    Now I don’t dare stop taking it…
    Well, whatever problem I had Oregano Oil cured it.

    rsm wrote on May 7th, 2014
    • What brand of Oregano Oil did you use? I would be willing to try it!

      Kathleen wrote on May 17th, 2014
      • I use one made in Australia by Solutions4health.
        It’s called “Oil of Wild Oregano”

        Roland wrote on May 19th, 2014
  20. What about Biohealth Diagnostics, Enterolabs and Cyrex? Did anyone try them? So may labs so little money? LOL They all test your gut.

    Alina wrote on May 7th, 2014
  21. Wow. Just, this is all blowing my mind. In the last year I cut out gluten and (through a couple accidental ingestions) realized it was causing my migraines. But now, if I get it, suddenly I get full-body joint pains. That’s new.

    Now recently I, out of nowhere, get the exact same reaction I get from gluten (migraine + joint pain) when I eat dairy, lactose really. Cheese is okay, but not frozen yogurt, cream, butter…

    I’m starting to think the real problem is my gut. What would be REALLY exciting, past the idea of maybe someday losing all the weight that just piled on unexpectedly, is that I may be able to try a new dish on my travels here and there and not worry about the possible gluten or dairy making me miserable. If I was healed.

    Man, that’s exciting. I need to learn to like these foods ASAP! THANK YOU!!

    Michelle wrote on May 7th, 2014
  22. Seems like the solutions you provided are similar to the solutions for acne..
    Not a coincidence.

    G wrote on May 8th, 2014
  23. Mark, super disappointed (and I’m not alone) that you recommended this webinar…a complete letdown. No new info, just an hour and a half of advertisement. Anyone who subscribes to you wants or needs to hear this elementary explanations.

    jen cordova wrote on May 8th, 2014
    • I agree, My husband and I sat down to watch the webinar. We learned nothing. You had more information in your blog post than they provided for us. We could have watch a couple episodes of the free thyroid sessions or even gone to bed on time.

      Regan wrote on May 9th, 2014
  24. I had the same experience as Jen and Regan. In addition to the shameless way they proceeded to sell to the audience, they didn’t even seem prepared for the talk. The fact that it was a ridiculously long presentation (it was nearly two hours before their cherry picked Q&A) really wasn’t helping them.

    Tristan Donofrio wrote on May 9th, 2014
  25. Mark, that is a very good post, thank you!

    I have chronic constipation. May it be caused by leaky gut?

    And what about non-gluten grains? If I want to heal my leaky gut, is it necessary to avoid all non-gluten grains (like rice, millet, oat, etc.) and potato, tomato as well?
    Please, help! :)
    Thank you!

    Anna wrote on May 12th, 2014
  26. A great way to clear out the wrong pathogens and clear the slate for the good bacteria is to take Immunoglobulin Y which is the antibodies found in chicken egg yolk. While fighting off pathogens a hen’s immune system generates millions of antibodies and also puts them into the developing egg yolk for the chick to have when it’s born. Chicks obviously don’t breastfed and need an aggressive defense right away. The antibodies are also effective for roughly 450 different human related pathogens. This is another reason why eggs are good for you. However when eaten with the rest of the egg most of the antibodies are digested in the stomach.
    There is a unique and new consumer product available which is capsule of purified Immunoglobulin Y, it’s called Vector450. Because it’s in a capsule and not combined with the rest of the egg components, when taken on an empty stomach the capsule passes quickly to the small intestine and the antibodies go to work binding to and eliminating pathogens. You can take probiotics with it since the antibodies will not bind to the good bacteria.
    The benefits are a much improved gut health and it acts as an immune modulator which means it supports a depressed immune system and calms down a over reactive immune system. That can have great results with minimizing allergies and relieving some autoimmune symptoms. Very cool results and very affordable!

    David Fyhrie wrote on May 14th, 2014
    • Thank you, that is very interesting!
      And what if I drink that egg yolk in my coffee in the morning? On an empty stomach?

      Does anybody know the answer : is it necessary to avoid all non-gluten grains, and potato, tomato as well when healing leaky gut?

      Anna wrote on May 16th, 2014
  27. You would get some IgY benefit from egg yolk but it’s limited for four reasons. Plus you would be getting a rather strange testing coffee. I personally do not like the idea of eating raw egg yolk;

    Reason 1) When the protein enters the stomach (each egg yolk has 2.6 grams of protein) then it will release acid to unfold the protein and pepsin (an enzyme) to cut up the protein into amino acids. IgY is a ‘functional protein’ by that I mean it has a specific function which is to bind to a pathogen. But it’s a protein and so much of it will be chopped up into amino acids and you lose the function that is so helpful for improved gut health.

    Reason 2) There are only about 25 milligrams of of pure IgY protein per capsule so on a empty stomach it can wash quickly through an open valve into the small intestine where it will not get stalled in a digestive environment of the stomach (high acid and pepsin enzyme).

    Reason 3) When you take two capsules you get about 60 mgs of pure IgY which no other product but Vector450 can offer and at an affordable price of $35 for a months worth. That’s a lot and you can take more if you need based on the level of stress you facing.

    Reason 4) You didn’t ask about a cooked egg but you should know that if the temperature gets to 60-70 C then the IgY protein breaks down and you lose the functionality.

    Go to the for guidance on a diet that fixes a leaky gut. It’s quite a complex issue. This is the website associated with the seminar that Mark recently invited everyone to listen to about Leaky Gut Syndrome.

    David Fyhrie wrote on May 16th, 2014
    • Thank you! :)
      But then, I don’t understand, why you wrote in your previous comment:
      ” While fighting off pathogens a hen’s immune system generates millions of antibodies and also puts them into the developing egg yolk for the chick to have when it’s born. …. The antibodies are also effective for roughly 450 different human related pathogens. This is another reason why eggs are good for you.”
      But thank you for your answer
      I registered for the seminar and it was very useful, thanks!

      Anna wrote on May 17th, 2014
  28. Sorry typo in Reason 3) I meant 50 milligrams of IgY for two capsules of Vector450.

    David Fyhrie wrote on May 16th, 2014
  29. I just learn something new and need to make a correction to my earlier post;

    In Reason 1) I stated that protein is broken down in the stomach by acid and pepsin into amino acids. That’s not correct. Protein is broken down into peptides in the stomach which are broken down in the small intestine by peptidase enzymes into amino acids which are absorb by the lining of the small intestine into the bloodstream.

    David Fyhrie wrote on May 16th, 2014
  30. Anna,
    You are right, I seem to contradict myself when I wrote that the Immunoglobulin Y (antibodies) are one of the reasons eggs are good for you but then I also wrote that when you eat eggs the digestive process in the stomach will breakdown the Immunoglobulin Y. However, like a lot of things in life…it depends. The Immunoglobulin Y is a tough immune protein and some can get through into the intestine but the more protein in the stomach (big meal with lots of eggs and bacon) then more could be digested.

    My company has extracted and purified the Immunoglobulin Y and put it in our product Vector450 with an increased amount per capsule equal to about 5 eggs. So on a empty stomach you will get a lot of it into the small intestine and even quite a bit will survive the stomach with food. Most people report much improved gut health, lessening allergies, relief from autoimmune symptoms and athletes getting faster recovery if they take 2-4 capsules a day with or without food. But you will get more into your intestine if taken without food.

    David Fyhrie wrote on May 20th, 2014
  31. Ok, so I’m really new to all this diet, nutrition and digestion stuff. Perhaps that is why this post left me more confused than anything.

    I understand the word “gut” as just a short-hand for “gastro-intestinal tract,” which includes the stomach, the small intestine, and the large intestine. They are three entirely different organs which perform entirely different functions. But isn’t what is called a “leaky gut” a problem with the small intestine only, which is where most of the nutrients in the food we digest are absorbed? And my understanding is that the vast majority of our intestinal flora, especially the “good bacteria” that we try to help maintain by taking/eating probiotics and prebiotics, live in the large intestine. When we get a lot of bacteria, even if they’re “good” ones, living in our small intestine where they don’t belong, that’s sometimes called “Small Intestine Bacterial Overgrowth” (SIBO), which is yet another problem with digestion that isn’t mentioned here.

    So that leaves me scratching my head as to why we’re talking at all, here, about probiotics, which belong in the large intestine, and prebiotics, which are intended to feed those bacteria, in a discussion of “leaky gut” in the small intestine. Could somebody please explain to me what I’m missing and how all this ties together?

    Greg Hill wrote on November 12th, 2014
  32. I eat fermented foods, take zinc, am fit like Mark is but younger (mid 30s, 6’2 175) but I have thought about how I might have “leaky gut” for some time now. I have to use psyllium precisely because I’ve had loose stools for a few years now.

    I think there is some balance thing going on here, possibly bacterial or yeast (candida?) but it’s odd because I’m such a healthy person otherwise.

    What should I do? Take that mannitol test? It would probably just confirm what I’m already suspecting. Mark, any tips?

    Kid Twist wrote on February 5th, 2016

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