It seems crazy, doesn’t it?
You’re researching acne and you end up on the question of probiotics.
You’re thinking: I started with skin, and I ended up on… intestinal flora??
I mean, sure, we’ve all heard of these little critters. The “good guys” of the gut. Our bacteriological buddies. We want to feed them, help them be fruitful and multiply, outnumber and knock out the bad guys, right?
OK, sensible enough.
But what the heck does any of this have to do with clear skin??
Quite a bit, it turns out.
(As in: if you thought having good gut flora was “nice” but irrelevant to skin health… read on, and be prepared to be astonished.)
One person claims: “Probiotics CURED my acne!!” Another says: “Probiotics caused me to break out!!” Yet another says: “Probiotics. Hmm. Interesting, but marginally effective, at best.”
So, what to believe?
Well, as a shrewd reader of the Internet, you know people believe whatever they want — which is just about anything. You’re a little more discerning than that. You know that issues as complex as skin health require you to dig deeper.
Plus, anecdotal “evidence” is nice, but you’d like to know what the actual research says, right?
Good thing you’re here.
We’re going “deeper,” all right — all the way down. We’re riding the Magic School Bus down the alimentary avenue. The eupeptic expressway. The lower GI. The gut.
Sounds delightful and magical, right? I know.
Here we go!
OK, so you don’t have to be an anatomy student to understand the gut’s role in processing food, absorbing nutrients, and eliminating waste. Likely, you can refer to your own, umm… experience for that.
But here’s another aspect to the gut you might not be aware of, and it bears pretty heavily on skin health: the gut represents a barrier between anything harmful you may have ingested (pathogens, toxins, and even hard-to-digest food) and your blood and lymphatic systems (hence, the rest of your organs and body tissue).
The gut is a part of the immune system. A major part. In fact, 70% of your immune cells are in your gut.
Now, even if you’re a super-conscious, nutritious eater, you can’t possibly know what kind of toxins and strange micro-beasties you might be consuming. But that’s okay: we don’t have to be all-knowing to be healthy.
We have some built-in defenses that handle things all on their own. The digestive system has been hardwired over millions of years of selection and genetic reproduction to keep us alive and healthy even if we’re inadvertently swallowing harmful stuff.
Consider the last meal you ate. The acid of your stomach is busy destroying microorganisms that don’t belong. Bile from your liver is secreting into your lower intestine, which, in combination with a number of other carefully selected enzymes, is working to break down lipids and proteins that would otherwise wreak havoc if absorbed into your bloodstream. The mucosal lining of your gut is busy catching any pathogens and antigens you might have unwittingly swallowed. It is also helping to produce antibodies against those pathogens – training the rest of your immune system to attack upon its command.
In a real sense, your gut is making the decisions about what is to be considered “self” and what is “invader,” and is teaching the rest of your body to act accordingly.
The gut is amazing, really. Digesting what you need, discarding what you don’t, keeping foreign invaders at bay.
You may already have noticed a nice parallel between the skin and the gut: both perform barrier functions. Both act as a fortress wall between you and chronic disease.
Here’s the thing about a wall, though: throw enough bad guys at it and eventually they will figure out how to scale it, break it down, or punch a hole through it.
Having a wall is not enough. You need an army to defend that wall.
Enter the gut flora.
You might have heard this one before: by sheer numbers, 90% of your cells are microbial (bacteria, fungi, etc.) and only 10% are human. Of course, human cells are a lot bigger, which accounts for why you don’t roll around looking like a massive blob of bacteria.
Still, it’s a startling number. A surprising amount of you is nothing but microbes.
All by themselves, your intestinal bacteria constitute 3 to 5 pounds of your bodyweight. Your gut is populated with tens of trillions of bacteria. (To visualize that number: if you had a dollar bill for every single bacterium in your gut, you would have not one, but three stacks of bills that reached to the moon. Jeepers.)
And here’s the plain truth about those plentiful little parasites: without them, we’d be sick or dead.
As amazing as your gut is, none of its functions, either digestive or immune barrier, would work as well as it does without your army of intestinal flora to help. The bad guys (bad bacteria, yeast, bugs, allergens, and even undigested nutrients) would eventually figure out how to break through the walls, conquer, and eventually destroy your body.
Having good gut flora is not just nice—it is essential. So essential that some scientists now refer to the gut microbiota as an “organ” in its own right.
Let’s look at a few things the gut flora are responsible for:
- Breaking down certain carbohydrates, fibers, starches, and sugars that the body cannot recognize and deal with on its own
- Increasing the absorption of water
- Reducing harmful bacteria (by out-competing them)
- Lowering the pH of the colon (making it inhospitable to certain harmful bacteria)
- Increasing the growth of cells necessary for the gut to function properly
- Triggering the production of proteins which prevent damage to the gut mucosa (and helping to repair damage that has already occurred)
- Training the immune system to identify pathogens
- Stimulating the gut mucosa to produce antibodies to pathogens
- Preventing allergies (by training the immune system not to respond to non-harmful antigens)
- Synthesizing certain vitamins that we need (notably B vitamins like biotin and folate, along with K2)
- Helping with the absorption of certain minerals, like calcium, magnesium, and iron
- Breaking down dietary carcinogens, which might otherwise lead to the development of tumors
- Preventing system-wide inflammation (Aha! That one should set the gears in motion as far as acne is concerned. More on this in a minute.)
Miraculous little microbes, aren’t they? Our friends, if ever we needed some.
Of course, all of this assumes a healthy gut microbiota—one that hasn’t become overwhelmed in its duties. When we overburden our systems with poor diet, toxicity, and stress, we make it very difficult for the gut flora to thrive and defend that wall.
When the gut barrier breaks down, what follows isn’t pretty: leaky gut, allergies, malnourishment, inflammation, mood disorders, tumors, and chronic diseases of just about every other organ in the body.
Yep. That includes the skin.
This isn’t a new idea. As far back as the 1930s, a pair of dermatologists, John Stokes and Donald Pillsbury, identified a causal connection between impaired gut flora, psychological problems, and acne.
They showed that patients suffering from emotional disorders (e.g., anxiety, depression) have altered gastrointestinal flora, which leads to systemic inflammation—which shows up on the skin.
It was a remarkable theory. They showed (with clinical results to back it up) that the gut, brain, and skin function together as a single, holistic system.
Unfortunately, it was a theory the medical world wasn’t ready for.
By and large, researchers forgot or ignored the gut-skin relationship for the next eighty years (with notable exceptions, which we’ll discuss in a bit). Dermatology entered an era of attacking the skin itself (with harsh chemicals and topical creams) rather than dealing with the internal problems that might be creating the acne in the first place. (For a detailed and gruesome description of just how horrible these topical solutions are for your skin and overall health, check out the “Conventional Acne Treatments” chapter of Devin and Sonia’s book, if you haven’t already!)
Thankfully, in the last few years, researchers have begun looking at the internals again, paying particular attention to gut flora.
And wouldn’t you know it? Overwhelmed, undernourished, or exterminated gut flora have been implicated in just about every skin condition you can think of, including eczema, dermatitis, rosacea, psoriasis, and yes… acne.
There’s a growing body of studies that link impaired gut flora to skin problems.
Let’s look at just a few.
One study from China showed the prevalence of impaired gut flora in a skin condition called seborrhoeic dermatitis (think “dandruff”) that mainly affects the scalp, but can also affect the face, neck, and chest. Not exactly acne, but it does establish a connection between gut bacteria and an inflammatory skin disorder.
This one is a little more up our alley: in a Russian study, 54% of the acne patients studied had impaired gut flora. Not overwhelming numbers, but check this out: the authors of the study were able to cut their patients’ treatment time in half by treating the gut dysbiosis. If you’re an acne sufferer, that should interest you.
Another study linked small intestinal bacterial overgrowth (SIBO) with rosacea, a skin condition related to acne (related, because they share a similar pathology, and often, symptoms). Basically, when you have SIBO, harmful bacteria like E. coli move from your large intestine into your small intestine and overpower what little microbial resistance they find there. This leads to all kinds of nasty things like nausea, constipation, diarrhea, bloating… you get the picture.
But, notably, SIBO also leads to intestinal permeability, a.k.a. “leaky gut.” “Leaky” is exactly how it sounds: undigested food particles and pathogens can pass through your intestine’s damaged mucosal wall and enter directly into your bloodstream. Bad! This provokes an autoimmune response (basically, in response to the foreign morsels, your blood brings the full force of its immune response against your own body) and left unchecked, leads to system-wide inflammation. As we know from other posts on this site, and from Devin and Sonia’s book, system-wide inflammation is a major contributor to acne.
Wait a second… Fecal coliforms? In the blood??
Yep. Pretty strong hint that acne patients have leaky gut, wouldn’t you say?
It’s all starting to paint a picture.
Finally, eight decades after the Stokes and Pilsbury paper from the 1930s, researchers are coming around again to the gut-skin connection.
The research seems pretty clear.
If you have skin problems, it’s a fair bet your gut isn’t in good shape either. There’s a good chance your gut flora are malnourished, overwhelmed, or severely underpopulated.
So what does the research have to say on using probiotics to help your gut flora?
Let’s take a look.
Earlier, we mentioned “notable exceptions” to the last eighty years of dermatology ignoring the gut-skin connection. In 1961, a physician named Robert Siver followed 300 acne patients who were given a commercially available form of Lactobacilli (a genus of bacteria that feeds on lactose and other sugars). He found that fully 80% of those acne patients showed clinical improvement.
A dramatic result, to say the least.
An Italian study in the eighties showed similar results. The patients who took L. acidophilus and Bifidobacterium probiotics showed improved clinical results to those who used standard care alone.
And a recent study (from 2010) showed clinical improvement of acne symptoms over a twelve-week period when the patients consumed Lactobacillus-fermented milk.
Given what you now know about gut flora, does any of this come as a surprise?
Make the gut flora flourish, starve out the acne. The clinical results back it up.
But the research goes deeper than mere clinical observations. Studies abound on the benefits of probiotics for just about every issue relevant to acne and inflammatory skin conditions.
Take a look:
- Probiotics reduce systemic markers of inflammation and oxidative stress (from heavy smoking, for example, in one study)
- Probiotics reduce T-cell-mediated skin inflammation
- Probiotics reduce levels of insulin-like growth factor 1 (IGF-1), a hormone-like substance that drives acne. If produced in excess, it increases inflammation as well as sebum production
- Probiotics mitigate food allergies (which can lead to acne)
- Probiotics help us absorb skin-essential nutrients, vitamins, and minerals
- Probiotics strengthen immunity against both gut-harming and skin-harming pathogens
- Probiotics increase water absorption and intestinal motility
- Probiotics prevent (and repair damage from) intestinal permeability, a.k.a. leaky gut syndrome 
- Probiotics reduce chronic psychological stress and mitigate the damage caused by chronic stress  (Psychological stress, of course, is a known trigger for skin diseases of every variety.)
- Probiotics help regulate glycemic levels, which, when they’re out of whack, contribute to acne
- Probiotics reduce total acne lesions after only weeks of treatment
What do you think?
It would seem, as far as acne goes, probiotics kind of knock it out of the frickin’ park.
Bottom line, if you’ve been struggling with acne “cures” and remedies, but you haven’t yet tried addressing your gut health, probiotics may be the answer you’ve been looking for.
All right, let’s say you’re sold. Fix the gut and the skin will follow.
But how do you begin to replenish that flora? Which of the 6,339,148 brands of probiotics at the grocery store will actually help your acne?
Well, “probiotics” covers a pretty broad range of little critters. Bacillus? Lactobacillus? Bifidobacterium? Streptococcus? Saccharomyces? Bacteroides? It sounds like an assembly of Roman Senators. There are beneficial bacterial strains by the thousands, and science is discovering more every day.
So where do you start?
Here’s the thing: “probiotic” is just a fancy way of saying “beneficial for living things.” There is a wide array of beneficial bacteria, and no single probiotic works the same for everyone. Our microbiomes are very individual, more so even than our fingerprints. There are trillions of those little guys and they all talk to each other and interact in a very specific way to get things done for your body.
Having said that, the research above seems to indicate that Lactobacillus has a broad range of benefits for everyone. It’s probably a good place to start. You may have heard of L. acidophilus before. It’s one of the most commonly used forms of Lactobacillus, for good reasons: it helps with the digestion of food, and in doing so lowers the pH of the colon and creates unfavorable conditions for pathogenic bacteria. Win-win.
We’ll recommend a couple of brands of pill-form probiotics, with the proviso that you may have to experiment with which ones are most effective, and in what dosage. You’re in charge here, not us. Do what works for you.
What Are the Best Probiotics to Buy For Acne?
Note: The following probiotic links are affiliate links, which means we receive compensation if you make purchases using these links. Visit our disclaimer page for more information.
Primal Defense Ultra by Garden of Life has a lot going for it, with several different strains of Lactobacillus and Bifidobacterium. They claim that three capsules a day will add 15 billion live cells to your existing microbiome, which is one of the higher counts we’ve heard.
AOR Probiotic-3 is another one. It doesn’t have Lactobacillus, but instead focuses on Streptococcus, Clostridium, and Bacillus. If you combined this with Primal Defense Ultra, you’d be getting a wide spectrum of beneficial bacteria. Again, experiment with what works. (Full disclosure, Sonia & Devin have not personally used this one.)
Finally, there’s Prescript Assist, which has a huge list of strains on the bottle (they claim up to 1229 symbiotic strains). This one has the benefit of prebiotics in the blend, too. (We’ll talk more about prebiotics in a minute.)
BUT… before you go rushing off to spend all your hard-earned money on capsules, let’s consider the downsides of pill-form probiotics.
The main issue with probiotics is this: are they actually still live cells or are you just consuming dead bacteria (i.e. throwing your money away)?
Of course the manufacturers claim they’re selling you live cultures, and a certain amount of them probably are. But it all depends on how long they’ve been sitting on the shelf, and under what conditions. Can you ever know, for certain, that the conditions were perfect all the way through processing, to bottling, to shipping, to arriving in your mailbox or shopping cart? That those boxes of capsules didn’t sit in a too-hot truck somewhere overnight, for example?
The three probiotics recommended above are shelf-stable (don’t require refrigeration), so are probably a safe bet. Of course, there is another way around the manufactured probiotics problem: take your probiotics in food form, instead.
The nice thing about food sources of probiotics: you can look at them and see the bacteria at work. Really. If it’s fermented and bubbly, you’ve got live microbes present, doing their thing.
You know you’re getting the real deal.
We’re not talking about conventional grocery store yogurt here (which typically uses only 1-2 strains of Lactobacillus). We’re talking about traditionally fermented foods, such as:
- Pickled, or lacto-fermented vegetables: e.g., cabbage (sauerkraut), turnips, carrots, eggplant, cucumbers (a.k.a. “pickles”), onions, squash. Again, these are not the ones sitting on your grocery store aisle shelf. If it’s live, it’ll be in the refrigerated section and say that it’s “live” on the packaging. You can also buy from a farmer’s market or make your own. Sometimes it’s as simple as throwing some stuff in a jar and letting the bacteria go to work for a few days! As Dr. Mercola put it: “Fermented veggies are your most economical route to optimal gut health.”
- Kimchi (personal favorite): this one I do buy from the grocery store, but you can tell it’s full of live bacteria since the lid of the jar is practically bulging with bubbly gases from the microbes inside. It’s an acquired taste at first, kind of spicy, and shockingly flavorful, but addictive. It’s full of beneficial Lactobacilli called L. kimchii—go figure. (Sonia and Devin make this at home – it’s not much harder than sauerkraut, just more ingredients.)
- Kombucha: a delicious way to drink your probies! Kombucha bars have become all the rage, and we always have a bottle on the go in our house. It’s essentially sweetened tea that has been fermented with bacteria so they’ve consumed most or all the sugars. What’s left is a bubbly, delicious drink that can be flavored in various ways or taken as is. Just be sure not to drink it while it’s still too sweet. Consuming the sugars before the bacteria do will have precisely the opposite effect on your gut flora. (More on sugar, in a minute).
- Fermented, raw milk: e.g., kefir, yogurt, or lassi (only if you can tolerate dairy and you are sure dairy is not a factor in your acne. See Devin’s article on the pros and cons of raw milk). Avoid the commercial, pasteurized versions: a) they are loaded with too many sugars, b) pasteurization kills the naturally-occurring beneficial bacteria, so you get only one or two inoculated strains, and c) pasteurized dairy has been linked with all kinds of health problems including allergies, tooth decay, osteoporosis, arthritis, and heart disease. Yuck.
To sum up, a sensible (and economical) probiotic policy would be:
- Take your probiotics in food form on a regular basis
- Supplement with pill-form probies when you have reason to suspect your gut microbiome might need extra help (after being sick, for example, or if you’ve ever taken antibiotics for acne – or any other reason).
Prebiotics refer to food which is indigestible by you (think soluble fiber), but which your gut flora thrive on. Essentially, by eating prebiotics, you are consciously feeding your gut microbiome directly.
Of course, if your gut flora are already underpopulated or wiped out, then eating prebiotics doesn’t help matters. As one person put it, it’s like the zookeeper “feeding empty zoo cages.”
You also run the risk of feeding the BAD guys if you’ve got too many of them already – Shigella, Clostridium, and Escherichia (E. coli). Gotta fix the imbalance first.
If you’re having gut issues (and consequent skin issues), you probably need to focus more on repopulating the missing bacteria than on what to feed them.
Once they are repopulated, so long as you are eating plenty of different sources of fiber (like kale, spinach, cauliflower, broccoli, mushrooms, sweet potatoes, etc.), you are giving the little guys exactly what they want. No need to go buy another set of pills.
Here’s how you kill off your microbial army. Chances are one or more of these are at fault in giving you your gut problems to begin with!
- Sugar/excess fructose (These actually feed pathogenic bacteria. Avoid!)
- Refined grains (especially white flour, which is fortified with iron in many countries – this iron can wreck your gut flora )
- Processed foods
- Vegetable oils
- Antibiotics (oral antibiotics kill bacteria throughout the body, including beneficial bacteria in the gut. In addition to avoiding antibiotics yourself, avoid food that has been fed antibiotics, e.g., conventional feedlot livestock and dairy.)
- Chlorinated and fluoridated water
- Antibacterial soaps
- Agricultural chemicals and pesticides
These are things we’ve all been overexposed to in modern life. They are now, unfortunately, the default mode of living. We have to strive to minimize them, or else all our efforts to improve our gut flora will be in vain.
Maybe you’re taking probiotics religiously, for example, but you’re also still exposed to pollutants, cigarette smoke, antibiotics, chemicals (topical, inhaled, and ingested), antibacterial soap, processed foods, chlorinated and fluoridated drinking water, sugar, and vegetable oils.
Well, guess what? Those good guys are getting killed faster than you can put them in your body.
The fact that we’re all exposed to these contaminants doesn’t mean you have no control over how much and how often. Minimize your exposure. Stop smoking. Stop using antibiotics and antibacterial soap. Switch to natural household cleansers and cosmetics instead of their chemical-laden counterparts. Install filters on your shower and kitchen faucet or buy filtered drinking water. Stop using vegetable oils. Buy organic. And, for the love of God, stop cramming down sugar!
Don’t assume doing one pro-health thing in isolation means you can keep right on doing everything else unhealthy. That’s just shooting your health efforts right in the face. And since we’re talking acne, we mean literally.
Speaking of which…
Unfortunately, the “miracle cure” mentality is alive and well on the Internet.
Here’s the straight dope: skin issues are complex. That means no miracle cure!
Think of it like this: your skin is the last stop on a long, complex journey. By the time acne and inflammation show up on your skin, the underlying issues have made stops at Stomach Junction, Gut Village, Blood Valley, Brain Town, and numerous other organs and systems along the way.
Here’s the good news: acne is a valuable, red flag indicator that something has gone wrong at one or more of those stations. It’s like Lassie showing up barking, telling you there’s trouble at the old mill.
(Modern dermatology, unfortunately, takes the approach of: “Get rid of the dog. Problem solved.” That’s why this blog exists – to debunk all that surface-treatment nonsense, and spread the good word about treating the root causes of acne.)
If you think about it, it would be very strange if our organs didn’t interact and pass their problems along to one another. The various systems in our body are connected. Why should heart problems only indicate heart causes? Why should liver problems only originate in the liver? Why should skin problems only start on the surface?
Same goes for “cures.”
It would be very strange if one single treatment was able to override all the other signals your body was getting, and just “worked” in isolation. Sure, taking probiotics might help balance your gut flora, but suppose you were still eating a diet high in omega-6 fats, thus triggering an inflammatory response throughout your body? It would be strange if your skin “ignored” the inflammatory response and simply healed itself simply because you were taking probiotics, wouldn’t it??
The body is holistic system. It doesn’t ignore anything you’re doing to it.
You could think of your skin like a report card. Remember taking that thing home to show your parents? All those little A’s and B’s didn’t matter if there was a dreaded D halfway down, did it? You knew what was coming: the frown, the angry glare, the stern “What happened here in Geometry, Billy?”
Your skin works the same way. Maybe you’re getting an A in “Fermented Foods,” but a C-minus in “Stress Management,” a D in “Sleep,” and an F in “Feedlot Dairy Avoidance.” You can’t “pass” (i.e., have clear skin) with those grades, even if you’re getting an A in Probiotics.
This is why we recommend a holistic approach to clear skin.
Your job, if you think about it, is to look for the things on your report card that aren’t doing so hot. If your gut flora is something you’ve ignored, it might just be the low grade that’s been holding you back. Add some probiotics and then check the report card again. See where else you can make improvements.
“Cure” is a bit of a telling word, actually. It says much about us. We’re so conditioned, especially in the West, to think of health and medicine as “pop this thing in your mouth and it will take your symptoms away,” rather than making health and wellness a lifelong pursuit in every area of life.
We’ve talked about some things to avoid – sugar, refined grains, antibiotic-laden animal foods, etc.
Another huge one that we’ve hinted at in this article: psychological stress.
Stress kills off your gut flora faster than anything else we’ve discussed. Researchers have shown that stressed mice, for example, possess only a fraction of the beneficial bacteria (and cannot replenish it nearly as quickly) as non-stressed control mice.
It makes sense. The brain, gut, and skin are a single, connected, holistic system. When one suffers, they all suffer.
The subject of psychological stress is too big to delve into here, and again, it is very individual. We all must take steps to reduce stress in our own lives, in a way that is meaningful for us and works with our lifestyles. Maybe that means spending more time outdoors, in nature. Maybe it means getting better sleep, or working fewer hours. Maybe it means taking regular yoga classes, or learning how to meditate, or trying acupuncture. Maybe it means taking up an instrument or pursuing an artistic goal. Maybe it means spending more time with neglected friends or quality time with the family.
Whatever reducing stress means to you, make the time to do it. Yes, it takes time, but the rest of your life will be more relaxed and fun.
The research on stress and health is conclusive. We can’t afford to think of chronic, excessive stress as “normal.” When it becomes normal, the damage is already done. If you’re one of those people who thinks: “I’ll rest when I’m dead!” you might want to re-think that one. You just might get your rest sooner than you think!
Remember, just because it’s “only” acne you’re dealing with doesn’t mean it’s trivial, or optional. The research is showing us is that acne and other skin problems are indicators of something more serious going on under the surface. Ignore it at your own peril!
And one last thing you can do for your gut flora, skin health, and overall health? Read this book: Clear Skin Forever!
- Your gut acts as a barrier between you and harmful pathogens, but it can’t do it alone. Researchers now believe thriving gut flora is essential to overall health.
- More often than not, skin conditions – like acne – go hand-in-hand with some form of gut dysbiosis. Dysfunction in one is almost always accompanied by dysfunction in another, and the lines of causality can go both ways. More and more research is confirming the brain-gut-skin connection, viewing them as part of a single, holistic system.
- Research confirms that probiotics help with just about every aspect of acne: reducing inflammation, regulating glycemic levels and skin chemistry, and helping with nutrient and water absorption.
- The key issue in deciding which probiotics to take is: how many live bacteria are there? Topical creams have almost none, pill-form probiotics have some, and raw, fermented foods have the most (and are generally the cheapest option). Another important consideration is the diversity of bacterial strains.
- Avoid sugar, grains, processed foods, vegetable oils, antibiotics, chlorinated and fluoridated water, and agricultural chemicals and pesticides. All of these hurt or eliminate your gut flora.
- Reduce stress. It’s not optional!
- There is no single, miracle cure that works despite other unhealthy areas of your life. Approach skin health holistically: find out what needs improvement, improve it, then move on to the next thing.
- If you want to approach your acne holistically, rather than with the flawed “miracle cure” mentality, read this book now: Clear Skin Forever. Your overall health will thank you, too!
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