
After 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.
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: http://ctt.ec/5f8B4+
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.
Drink bone broth, eat gelatinous cuts of meat. 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 intelligently. Intense, 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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81 Comments on "A Primal Primer: Leaky Gut"
I don’t have intestines. Just a sieve.
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.
Samesies!
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!
“…if one starts out from…”
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.
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
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.
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
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.
+1
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!
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.
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.
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.
What does the benadryl do for you? Stop allergic response?
‘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?
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!
Thanks Krissy – that makes sense!
Mark, thanks for the Gut Check.
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.
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.
Aaah, unbiased, evidence-based recommendations – you just gotta love them.
Not sure I remember the Demi Moore section of Mark’s book 🙂
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.
My thinking is – if you are still feeling soreness from your last run, wait another day to run again. This applies to any exercise.
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!
Ha! Even when I caught myself clearly overtraining I wasn’t sore, running has other sneaky ways of catching up on a person though.
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.
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 🙂
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?
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…
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 — 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!!
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! 🙂
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.
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.
But can the old-skool Paleo crowd hear that raw cow colostrum heals? They are so invested in hating dairy…
That’s an incredible story, Shannon. Congratulations on solving these problems. Was it wheat that caused all of them?
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
Which protocol did you follow did you take any supplements? Would love to know I’m scarred with eczema since 20 years and have leaky gut.
Thanks
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.
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.
Winner or loser, depending on your sense of humor ;]
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, 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.
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.
What brand of Oregano Oil did you use? I would be willing to try it!
I use one made in Australia by Solutions4health.
It’s called “Oil of Wild Oregano”
What about Biohealth Diagnostics, Enterolabs and Cyrex? Did anyone try them? So may labs so little money? LOL They all test your gut.
…I did enterolabs but they don’t tell you if your gut is leaking, they just tell you sensitivities. I had none and yet I still had leaky gut!
Seems like the solutions you provided are similar to the solutions for acne..
Not a coincidence.
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.
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.
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.
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!
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?
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!
Sorry typo in Reason 3) I meant 50 milligrams of IgY for two capsules of Vector450.
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.
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?