The Gut-Skin Axis

The Gut-Skin Axis

One cause of acne is about as far away from the skin as we can get: in the gut. There’s good reason to believe that the health of your skin depends on what happens in your gut.

We know from research that gut issues are more prevalent in people with skin conditions. And the same studies show that if you treat those gut issues you can expect your skin to clear faster.

On this post I want to talk about this hidden cause of acne – hidden because in most cases these gut issues don’t cause any noticeable symptoms. And hopefully make acne just a little bit less mysterious and arm you with another weapon against acne.

Primer on gut problems: dysbiosis and leaky gut

Gut issues can mean many things. So let’s first understand the problem.

Broadly speaking there are two types of bacteria living in the digestive system: the so-called good bacteria (probiotics) and the so-called bad guys. In pure numbers there are more bacteria in your gut than there are cells in your body. And when things are in balance these little guys are absolutely essential to your health. For example, they digest certain foods and manufacture vitamins for you to use.

But this can turn into a real problem if the bad guys take over, for example as a result of too much stress, bad diet or excessive antibiotic usage. This is a condition known as gut dysbiosis or small intestinal bacterial overgrowth (SIBO). The harmful bacteria can interfere with digestion and produce toxins.

Normally the gut wall keeps these things out of your body. Despite being just a few cells thick it’s a very effective barrier; nutrients can enter the body but keeps toxins and other harmful stuff out. SIBO can change this.

The harmful bacteria produce corrosive substances that attack the gut wall. After a while tiny, tiny cracks appear, and though these cracks molecules that normally would be kept out can enter the body. This is known as leaky gut syndrome or intestinal permeability.

The substances that can leak into the body include:

  • Bacteria, virus and fungi
  • Incompletely digested food
  • Toxins from bacterial metabolism

This is not without consequences:

  • Increased chronic inflammation. This is really bad for the skin as acne patients are already under heavy inflammatory load.
  • Can cause food allergies. The immune system treats incompletely digested food particles as invaders and attacks them. This can ‘teach’ the immune system to always attack specific foods and thus lead to food allergies.
  • Possibly increases stress and emotional problems. One study with 1641 patients with gut issues showed that anxiety and depression correlate strongly with SIBO. Another study showed that treating gut issues improved depression and emotional problems.
  • Discomfort and gas
  • Nutrient deficiencies as a result of incomplete digestion

No symptoms

Pinning down these gut issues is difficult because the vast majority of people never experience any overt symptoms. And what minor symptoms they may experience are often disregarded as just normal rumblings from the tummy. That’s why many acne patients never suspect gut as the origin of their skin problems.

Acne-gut link

This is not just theoretical speculation. Several studies have demonstrated a link between acne and gut issues. For example:

  • One study looked at 114 acne patients, or which 54% suffered from SIBO (much higher than population average). Then they divided the SIBO sufferers into two groups. One got ‘intestinal microflora-correcting agents’ and the other group didn’t. The treated group cleared twice as fast.
  • Then there was a Korean study that looked on the effect of Lactobacillus-fermented dairy beverage on acne. They found that the fermented beverage reduced inflammatory acne by 40% and total pimple count by 23% as compared to placebo.
  • One study showed that SIBO is 10 times more prevalent in rosacea acne sufferers than healthy controls. And treating SIBO with antibiotics completely cleared rosacea for 71% of the patients and improved another 22%. Though it’s not clear from this study if the improvement was because of improvement in SIBO or some other antibiotic effect.
  • Doctors have suspected a connection between gut and the skin for at least 50 years now. An older study showed that people with acne have a far stronger reaction against gut bacteria. This suggests that the bacteria have leaked from the gut and primer the immune system against them.

I could show you some other studies also, but I don’t want to turn this into a complete medical review of the topic.

And if we compare acne patients to people with clear skin

  Acne Clear skin
SIBO More Less
Inflammation levels More Less
Antioxidants levels Less More
Food allergies More Less


Let’s summarize what we’ve learned so far:

  • Acne patients have higher levels of systemic (all over the body) inflammation than people with healthy skin. And acne seems to get worse with increased inflammation.
  • Gut issues are a major factor in systemic inflammation.
  • Studies show that we can clear or reduce acne by treating the gut issues.

I have to insert a disclaimer here before people jump into conclusions. Science is messy and studies often contradict each other. So while the studies all seem to indicate a link between acne and gut issues, it’s not enough to draw rock –solid conclusions. But we can say there’s more than enough reason to suspect gut issues play a role in acne formation.

What causes gut problems

Here are some things that can contribute to gut problems:

  • Excessive antibiotic usage. Antibiotics often kill both the good and the bad bacteria. And long-term antibiotic usage can wipe out a significant portion of the gut bacteria, and thus open the door for the harmful bacteria to take over. This is why it’s not a good idea to treat acne with oral antibiotics. They only offer a short-term solution and can cause long-term disaster.
  • Too much stress
  • Sleep deprivation
  • Low stomach acid
  • Eating processed foods
  • Lack of plant fiber and other pre-biotic foods

How to treat gut problems

Unfortunately we don’t have enough research to come up with clear treatment guidelines, and the Internet is full of contradicting advice. Still, here are some common sense things that should help:

  • Use antibiotics only when you absolutely need them. Also, you talk to your doctor and ask for an antibiotic with minimal effect on the probiotic bacteria.
  • Fermented foods and probiotic supplements.
  • Eat minimally processed food, and make sure you include plenty of plant fiber (fruits and vegetables) into your diet.
  • Do your best to manage stress.
  • Make sure you get enough sleep.

Summary and take-home messages

We now have good reason to suspect gut issues contribute to acne (and other skin problems). 1) Gut problems are much more prevalent among acne sufferers, and 2) treating gut issues usually also helps the skin. This is not a universal One True Cause for acne, but rather one more avenue to explore in your fight against acne.

For treatment the best options are avoiding excessive antibiotic usage and taking probiotics either in the form of fermented food or supplements. Stress management and overall healthy diet should also help.

About Me

Hi, I am Acne Einstein(a.k.a. Seppo Puusa). I'm a bit of a science nerd who is also passionate about health. I enjoy digging through medical journals for acne treatment gems I can share here. You can read more about my journey through acne and how I eventually ended up creating this.

20 thoughts on “The Gut-Skin Axis”

  1. I’m surprised no one has commented on this article, when it’s quite common among acne people, either way. I got tested for dysbiosis and the results came back positive. But I’ve been thinking about it for months now. I’ve had runny stools for as long as I remember. I hope it’ll make a positive impact on my skin now that I’ll be taking antibiotics and probiotics

  2. My n=1 supports this theory even though I have no clinical tests to back it up. Just clear skin! I suffered from acne from age 11 to 38. Face/neck/chest/back/shoulders…sometimes angry and cystic. Worse if constipated. It comes down to the gut bacteria, so follow the weed/seed/feed method. I didn’t do it in that order because I had no protocol at the time. Took saccharomyces boulardii to lower levels of any possible gram negative bacteria or candida, 50 billion probiotics to increase the beneficials, l-glutamine to heal intestinal permeability, curcumin for inflammation, homemade kombucha and kimchi for fermented foods, veggie fiber to feed gut bacteria.

    I’m not totally healed yet as I still can’t eat certain fermentable fibers or resistant starch type 2 without a lot of discomfort, and corn will give me constipation and a breakout. Not everyone is sensitive to the same foods but we all may have a form of dysbiosis or SIBO. But my body acne is gone and face only gets occasional small bumps that go away on own. No more red pimples. I also dont use soap on face anymore…just gentle microfiber cloth and aloe vera gel.

    • Glad to hear you are doing better. I suspect that many people with acne have some form of gut issues without even realizing it since the symptoms in most cases are fairly mild. I know that I never suspected there was anything wrong with my gut until I started paying attention. Now it’s obvious to me I have relatively mild IBS and that it’s linked to my skin.

    • Thanks for sharing Genny. A quick comment on those studies. I would take them with a grain of salt. Highly, highly preliminary. What they did in that study was to give vitamin D supplements to vitamin D deficient rats who were also given ‘toxin’ to induce intestinal damage. They showed that vitamin D prevented some of the intestinal damage. This doesn’t mean that vitamin D supplements would be helpful for humans, especially for people who are not vitamin D deficient.

      I’m not saying that vit D doesn’t help. Just that we can’t conclude anything based on this study.

  3. Hi Seppo,
    I was wondering, are these gut problems related to all types of acne? I have cystic acne as well as hundreds of clogged white heads all over my face. May this still be cause my gut problems?

    • Sorry but there’s no way to answer this question. Research shows that gut problems are linked to skin problems. But does everyone with acne also have gut problems? We don’t have enough data to answer that, but I suspect not.

  4. DAar Seppo,
    I m the right to comment this article. Why?
    Italian, 25 years old, I am intolerant to lactose and I do not eat meat since 2011. I eat vegetables, fresh and dried fruit, fish. One year ago, I started having a lot of gut problems, no matter what I ate (no pain but gas and especially persistent soft stools, sometimes diarrhea if I eat legumes or lactose or drink alcohol)the fact is that:
    1 before, even if I knew I was intolerant to lactose I sometimes used to eat cheese and it was ok, unless I exceeded in quantity. I ate legumes without ANY problem. Problems with legumes began suddenly!I don’t eat no cheese now.
    2 Acne and dermatitis : I’ve always had, since I was 14 ,a Moderate acne, no cystic, on my chin, and a more important acne on my back. I had also on my chest but growing up it has become very mild and most of the time this part is clean. Now, I never really cared about my face because it was moderate And I did not want to spend money on dermatologists, BUT in the last 2 months it has got worse, pimples does not disappear, there are a few on my cheeks and chin pimples leave red spots and they keep on appearing everyday and it NEVER happened to me, before they used to stay some days and leave without red marks… it is depressing me.
    3 i see a gastroenterologist for my gut problems, I have done a lot of exams and analysis but nothing came up. I am doing an homeopathic cure and I am trying to eliminate gluten from my diet (I’m thin but I am trying to eat law insulin foods but it’s not easy because I cannot eat anything!! I also drink green tea and dandelion)
    4 I saw a dermatologist, she proposed two types of Cure, one is topics+antibiotics+probiotics the second option is, to my surprise…..isotritonein!!!!! I didn’t expected it as it’s not severe acne! Now I want to try the first cure but I am afraid to go on antibiotics as it could aggravate my gut situation
    4 AND MOST IMPORTANT: why doctors don’t say that my gut could be related to my acne????? Why gastroenterologist just say “ask your dermatologist”??at Least my dermatologist said THERE IS a connection and she associated probiotics to the cure!and why nobody think about food or inflammation from food?? Everyone has a different idea and I am forced to pass my time reading websites, articles, forums, to try understanding something!
    I would love to cure my body and skin from the inside and not repress its manifestations (I think acne is that), I would love to know what Food is bad for me (or whatever is the problem with my gut since one year) and avoid isotritonein….
    What is your opinion?

    • Hi Ila,

      I’m not quite sure what you are asking, but here are a few observations based on your comment.

      1. Look into low FODMAP diet. Beans are high in FODMAPs and the fact that they cause problems for you suggests you might have FODMAP issues. They are usually caused by bacterial overgrowth/imbalance in the digestive system.

      2. Probiotics could help but they could also cause problems. Taking probiotics sometimes makes things worse for people with bacterial issues in the gut. They always make me constipated and cause acne.

      It’s hard to comment more than this without knowing more about your situation.

      • Dear seppo,
        Thank you for your advices. I had already checked the list of Fodmap foods you posred and I wanted to print it to try avoid some foods, anyway it says fruits like apples and pears are “bad” if you have this kind of issue qhile banana is better, and actually for me is just the opposite! But i guess it depends on one’s body.
        About probiotics, i really thought they could have been just good for my gut and acme situation:( the probiotics im taking are supposed to be good especially for the skin, they are prescribed for dermatitis etc…i did several tests to look for bad bacterias in my gut but it seems i am ok!i repeated them several times. i hope they will help me because at the moment i feel so depressed, i spent so many money for doctors, analysis, drugs. And nothing works.
        IM also trying ti avoid other foods, like gluten products and almonds (ive been eating a lot of almonds in the past months and i am really trting to think about which food i didnt eat that much before), also i suspect about my new make up and new tools for it, because whats happening to my face is so strange, i was waiting my acne to disappear being 25, and it has increased instead. Also it would be nice to see an article about biocosmetics prodycts on your blog….i know your male but you are really good in writing and you always quotes studies etc….moat people say its good to use these products to fight acne but since i use thrm my skin got so worse:((
        I am so confused!

        • I’m not saying probiotics are bad for everyone. I’m saying that in some cases, especially for people who have constipation, they can make the problem worse. On the other hand, there are studies that show they help some people who have skin problems. It really varies from person to person and it’s almost impossible to give advice that would work for everybody.

          I’m sorry to hear you’ve spent so much money on doctors and tests with no results to show for. I’m not sure how accurate or useful the gut bacteria tests are. I haven’t looked into them in detail, but I wouldn’t be surprised if they are unreliable. In my experience, trial and error and testing things is much better than laboratory tests.

          Do you have a link to biocosmetics website? I can look into it but it will take some time as we are on holiday in Europe with my wife (in Florence at the moment).

  5. Thanks for this article. I recently picked up a probiotic supplement and I’m adding more vegetables to my diet.

    I think the “managing stress” part is the most difficult in college–but I know that exercise helps reduce stress.

  6. Hi seppo, I don’t have any of the common symptoms of SIBO like bloating or rumblings. However, I’ve narrowed it down that I am highly sensitive to sweets (e.g. cakes, donuts, etc) and I get really bad breakouts even if I consume them in small amounts. Do you think this could be a SIBO symptom? and how do you treat it? Ive read about herbal supplements but I’m not sure what kind to take…thanks for your response!

    • That doesn’t sound like SIBO. If you had SIBO you would likely be ‘sensitive’ to wider range of foods. In SIBO the culprits usually are rapidly fermented carbohydrates, which causes gas and bloating in the small intestine, which in turn leads to a host of other problems.

      Sensitivity to sweets sounds more like a hormonal-acne type issue. In such cases overall carbohydrate, sugar and dairy restriction usually helps.

  7. hi seppo,
    After reading this article I am wondering if I could have found out that gut problems are the cause of my acne. I have had on and off mild acne for about 4 years, and was eventually put on doxyclicine for a few months, and since I stopped taking it I practically couldn’t stop breaking out. My acne is not completely severe but i could just not stop continually breaking out in the same places, especially my right jawline and neck area with cystic and really red acne as of recent. It is also sometimes on my left side as well but not nearly as bad there. It is the type of acne that may die out but will leave marks. I broke out in that same area last year, it went away for months, but now it is back. I also break out near the creases of my nose often with whiteheads. Im not sure if this information is completely relevant but I am wondering if gut issues are in fact my problem, or if it is hormonal. Because of my past antibiotic use i would suspect gut issues but i’m really not sure. To give you a breakdown of my diet, it consists of high grains/carbs, a lot of meat, but very little sugars and dairy, and a not many fruits and vegetables. I also consume a lot of alcohol and and constantly stressed and have a poor sleep schedule, being in college. After reading this, it just left me wondering that if gut issues are in fact the cause of my constant and recently cystic breakouts, then what it the next step? how do I fix my gut issues and work on becoming healthier? I feel like in this article you just pointed out the potential problem but didn’t really make any suggestions on how to go about fixing the problem. I have heard going gluten free and limiting carbs and dairy could be a solution, but i know i already don’t eat much dairy so that probably isnt the issue for me. I am looking for any advice I can get at this point, because when i go to the dermatologist they will just prescribe me a product that may help reduce symptoms, but they never actually help and completely curing me with whatever I am doing wrong that is causing my acne in the first place.

    • It’s a few years since I wrote this and at that time didn’t know too well how to deal with gut problems. In your situation, my first suggestion would be to try a low-FODMAP diet for at least a couple of weeks.

      FODMAPs are rapidly fermented sugars, and their fermentation creates a lot of gas in the intestines. Some people, like me, also have too many bacteria in the small intestines, which really can’t handle large amount of fermentation gasses. Low FODMAP diet reduces the amount of substrates available for fermentation, which can be helpful for people with gut issues, especially IBS.

      If low FODMAP diet works, it suggests you have a bacterial overgrowth/imbalance in the gut, and you might benefit from a more comprehensive gut healing protocol.

  8. It seems I’m a bit late to this article but my mom sent me this link after battling acne for 3 years straight. I tried everything, topical creams, antibiotics, face washes you name it, nothing took my acne away. It was cystic and it was massively inflamed. The spots would be swollen and red for a week at a time.

    I had cut out all dairy and as much sugar from my diet as possible. I read this article and realized I really hadn’t been been consuming prebiotics or probiotics. I went to the store and bought a probiotic supplement, a few bottles of kombucha, and some plain yogurt. I kid you not the huge inflamed pimples were gone in 2 days. I had detox acne that is small white bumps under my skin but it’s different than what I have been dealing with for years and they aren’t inflamed like before. This article saved my skin!

  9. I cut wheat products, refined sugars, and cut dairy almost completely out of my diet and am juicing and eating mostly unprocessed foods. I’ve had to take antibiotics for cystic acne for most of my adult life but I’m off the antibiotics and my skin is clear. I’m not sure which one was causing the acne but it was definitely diet related. I don’t know why dermatologist say what you eat doesn’t affect your skin.

Comments are closed.