Gut Health and Acne: The Gut-Skin Connection

Your skin is a direct reflection of the health of your gut. It’s like a mirror: if your gut is healthy, your skin is going to reap all the benefits and glow from the inside out. But if something is wrong in your gut, that’s when skin problems like acne start to emerge.

When my acne was at its worst, my gut was an absolute warzone. I had one of the worst bacterial imbalances experts had ever seen, a leaky gut, numerous food intolerances, nutrient deficiencies and a bucket-load of inflammation. And all of it literally manifested on my skin as cystic acne along with a plethora of other symptoms. It wasn’t until I addressed the mess that was my gut that my skin finally started to heal.

All disease begins in the gut  - hippocrates (460BC)

The recognition that the gut and skin are connected is not a new concept. Traditional Chinese medicine and Ayurveda (the traditional medical system of India), both of which have been around for thousands of years, believe that all health and disease centres around the gut. Western Medicine is a bit like a tortoise in this race, and has only just caught up to this concept in recent years.

WHat Is the Gut?

Your gut is the epicentre of your body, your second brain, the assistant coach to your team, the vice president of the country. Okay you get the point.

The anatomy of the gut is your gastrointestinal tract – the pathway from your mouth to your rectum – in addition to the accessory organs (like the liver, pancreas and gallbladder) that are all involved in the digestive process. It is a 30 to 40 square meter tract (yes half a badminton court fits inside your body) and is lined with over 100 million nerve cells [1,2]. It houses an entire ecosystem of bacteria, metabolises hormones, produces neurotransmitters, absorbs nutrients, and holds 70% of our body’s immune system [3]. How’s that for a resume’?

How is the Gut and Skin Connected?

What symptoms come to mind when something’s wrong in the gut? Bloating like you’re 6 months pregnant? Increased gas you’re trying to hold in? Bowel issues that send you running for the toilet (or backed up for days)? And probably stomach pain that has you in the fetal position? But what many don’t realise is that most skin issues like acne, psoriasis, rosacea can be a huge warning sign of poor gut health.

But how can issues in the gut affect the skin? Let me introduce you to the gut-skin axis.

The gut- skin axis, in simplistic terms, is the connection between your gastrointestinal tract and your skin. Think of it like a constant pathway of communication (it’s also connected to the brain in a 3-way communication – but this blog post would be FAR too long if we got into that now).

There are multiple mechanisms in which the gut can influence the skin and cause acne. Each of these mechanisms do not exist in isolation – they are all interconnected and affect each other. The gut can affect the skin through:

  • the integrity of the intestinal wall
  • the gut bacteria
  • the gut’s influence on our hormones.

There’s Holes In Your Wall

The one cell thick gastrointestinal lining has a two-part purpose: 1.) To absorb small micro-molecules (like digested food particles) to be used as fuel and other processes throughout the body. 2.) It acts as a barrier that prevents larger molecules, bacteria and toxins from entering your blood stream. It’s like your Great Wall of China, preventing invasion into your body.

Leaky gut or intestinal permeability is when there are large cracks or holes in the gastrointestinal lining. These holes allow undigested food particles, bacteria and toxins to leak out into the bloodstream. The body sees these as “invaders” and goes into attack mode to initiate an immune response to this unknown substance. Overtime, it can cause a vicious cycle of inflammation, increased food sensitivities and nutrient deficiencies.

Tight junctions hold the cells of the gut together. A healthy gut has a strong intestinal wall with normal tight junctions that prevents large molecules, toxins and bacteria to cross into the body. When the gut is leaky, the tight junctions are affected, causing gaps in the wall. Unwanted substances enter the body through these gaps or through the damaged cells into the bloodstream causing an immune response.

How Does This Relate To Acne?

Studies as early as 1916 have suggested the link between acne and leaky gut showing that increased intestinal permeability is an underlying issue for a significant number of acne patients [4, 5].

Here’s why: leaky gut allows toxins to enter the bloodstream and travel throughout the body which causes systemic inflammation that wreaks havoc on the skin. It also makes the liver work overtime to remove these toxins from the body. When the liver’s overworked, the skin becomes the next port of call to get rid of these unwanted toxins (it is the largest organ of elimination after all).

Not only this but leaky gut stops us from getting the essential nutrients we need for optimal skin health by reducing absorption and “leaking” undigested food particles into the bloodstream. When we have less nutrients absorbed, the body is smart and will always prioritise giving the good stuff to your vital organs to keep you alive rather than your complexion – justified I guess.

Who’s Living Inside – Your Gut Bacteria (aka the Microbiome)

The gut microbiome refers to all the micro-organisms and their genetic material that live inside your intestinal tract. It is a bustling ecosystem of bacteria, fungi, viruses and other organisms and is the largest ecosystem in the body, housing 100 trillion bacteria within the gut [6,7]. That’s over 10 000 times the number of people on this earth inside your gut!

Our gut bacteria are powerhouses; they influence the immune system, breakdown food, produce essential nutrients, protect against pathogens and support the lining of the gut. Those “butterflies in the stomach” when you’re nervous or talk to that cute guy from the office? – your little bacterial ecosystem produces chemical messengers (neurotransmitters) than can affect our mood and anxiety. Feeling happy? You can thank those good gut bacteria that are producing 95% of the body’s serotonin, your feel-good, happy hormones [8]. This is why the health of your gut microbiome can play a massive role in mental health disorders like depression and anxiety.

How can gut bacteria affect the skin?

Though not fully understood by science, it is suggested that the microbiome can communicate with the skin indirectly via the immune system but also directly through their metabolites (what the bacteria produce) [9,10]. The metabolites produced by the gut microbes can influence cell regeneration, lipid metabolism (which is important for a strong skin barrier) and inflammation [14,28].

Let’s say our gut was like a home. When our gut health is strong and we have an abundance of different types of good bacteria housed in there, our skin is going to reap the benefits. However, when we have dysbiosis or a bacterial imbalance, all the rooms in our house become overcrowded with uninvited party guests like bad bacteria and pathogens. Like a party gone wrong, they trash your house and overpower the normal bacteria. That’s when the skin starts to suffer.

Your gut is like a home. A healthy gut has an abundance of good bacteria living in all the rooms. When there is an imbalance of bacteria in your home, pathogens and other bad bacteria overcrowd the rooms wreaking havoc on your home leading to a range of symptoms including acne

Multiple studies have shown that acne patients display a distinct bacterial composition and decreased bacterial diversity [11,12]. Meaning that acne patients have less variety of bacterial species and all have similar types of bacteria in their gut ecosystem (and it’s not the ones we want).

Further studies show that adults with acne rosacea have 10x more rates of SIBO (small intestinal bacterial overgrowth) compared to healthy controls [13]. Basically, people with acne have more bacteria growing where they shouldn’t be growing – like they’ve migrated out of the house and are trashing your shed too

Where it can go wrong

Bad bacteria and pathogens can cause leaky gut (see above). When they create ‘holes’ in the intestinal wall, the pathogens and toxins the bacteria produce can quickly enter into the bloodstream and negatively impact the skin [14,15]. They can cause inflammation when the immune system goes to war against these pathogens and toxins that have now invaded the bloodstream [15,16,17].

The overgrowth of bacteria and pathogens can also compete with your body for nutrients. Just like a leaky gut, the skin is not getting any of the nutrients it needs to maintain clear skin [14]. When you’ve got leaky gut AND bacterial dysbiosis (which is extremely common) that’s when the skin really starts to struggle.

Hello Hormones

It may not seem like it, but the gut is considered to be the largest endocrine organ in the body, producing more than 30 hormone-like compounds and neurotransmitters [11]. In other words, your gut is a hormone factory – it produces hormones and responds to hormones produced by the body.

Some hormone-like compounds are produced by the microbiome and are released from the gut into the bloodstream to work on organs all over the body, including the skin [11].

There is some level of evidence to suggest that the gut influences our male sex hormones (which is a major culprit of acne) [6]. However, one of the most notable skin-influencing hormones that is impacted by the gut is estrogen.

There is a whole section of bacteria in the gut that are responsible for processing estrogen. These bacteria are known as the estrobolome. For the nerds like me (skip if you can’t be f’ed): these bacteria produce an enzyme called beta-glucuronidase which causes estrogen to be re-circulated back into your body instead of being excreted out through your poop [18]. In other words: when there is an imbalance of these estrogen metabolising bacteria it can cause a deficiency or an excess of estrogen in the body – both of which can be negative for the skin.

Similarly, dysbiosis in the gut can cause constipation – a consistent complaint of acne patients [19]. When we are constipated, toxins and estrogen are reabsorbed back into the body causing estrogen dominance and can cause acne

How to Support your Gut Health and Your Skin

I feel like the phrase “gut health” is now as popular as Gangnam Style was in 2012. With so much noise on the internet, here’s all you need to know when it comes to supporting your gut whilst also ensuring you are optimising your skin (I mean if I can come back from the warzone state of my gut with these things – than you can too!)

1.) Diet

For optimal gut health you want to ensure you are feeding your amazing little gut bacteria and supporting your gut lining. You want to be eating a diverse wholefood diet with an abundance of plants, high quality fats, proteins and complex carbohydrates.

But avoiding things that are inflammatory to the gut is just as important as adding things into your diet.

*Gluten has been shown to increase the gaps in the intestinal wall and cause leaky gut (even in people without gluten sensitivity) [20].

*A high sugar and high GI diet (foods that are rapidly absorbed into the blood stream) can cause an overgrowth of pathogenic or bad bacteria that feed on these foods. It also can contribute to leaky gut leading to further inflammation [21,22].

*Avoid inflammatory oils like vegetable oils, canola, sunflower oil, peanut oil (there’s a list just google it) which can contribute to inflammation of the gut.

*Watch out for food sensitivitiesWhen you have an impaired gut lining and an imbalance of bacteria, you can become sensitive to certain foods that were once fine for you to eat. While you heal your gut you might have to avoid certain foods for a while that could be causing symptoms and inflammation in your body while you clean up your gut. It’s important to work with a practitioner to guide you through the elimination and reintroduction phases.

2.) Prebiotic and Probiotics

These two words might sound the same but they are vastly different. Probiotics are like putting more bacteria into your body while the prebiotics are the foods that feed them.

Prebiotics are foods that pass through the GI tract undigested until it gets to the large intestine where it feeds all the good gut bacteria. Without a diet full of prebiotics, you end up starving those amazing good bacteria – which we know are SO important for your gut, body and skin!

Though more research has to be conducted in this area, probiotics have been suggested to have benefits to patients with acne by reducing systemic inflammation, increasing nutrient absorption, and altering the microbial ecosystem of organs outside the gut, such as the skin [4,19,23,27,28].

Skin Tip: Try incorporating a broad spectrum probiotic and probiotic foods to your diet (like miso, kimchi, sauerkraut, dairy-free yoghurt). Also ensure that your diet includes prebiotic foods that will keep your gut bacteria thriving (examples are artichokes, garlic, onion, leeks, pomegranate, chickpeas, lentils, cashews and more).

3.) Get Your Body Moving

Studies have shown that regular exercise can positively alter the gut microbiome [29]. A stronger gut bacterial ecosystem = better skin (in a nutshell). It also helps pump your lymphatic system to remove wastes and toxins from the body. A well functioning lymphatic system means that the toxins wont be pushed out through the skin and cause acne.

4.) Be wary of antibiotics and other medications

I’m not saying to never take medication or antibiotics because there IS a time and a place for it. However unfortunately our medical system sometimes overprescibes antibiotics when there is no need. Antibiotics are like an atomic bomb to your gut that wipes out the good AND bad bacteria. Similarly, the contraceptive pill can affect the balance of gut bacteria – which is something to be aware of if you are taking.

5.) Alcohol in moderation

Love a red wine with dinner or an espresso martini with the girls? Although it’s not a direct cause, alcohol can trigger acne. A big night out can dehydrate the body, overwork the liver, disrupt hormones levels, cause gut inflammation and can increase the number of pathogenic bacteria in the gut [24,25,26]. Mixed drinks are also full of sugar which gives you a double whammy when it comes to causing an acne flare-up.

Skin Tip: If you’re sensitive to alcohol, try going for the clear liquors like vodka or gin (and not mixing it with another sugary drink). Keep a trigger diary around alcohol – is there different types that break you out: maybe wine’s no good, but vodkas okay? And aggressively hydrate before and after you start drinking.

6.) Take Digestive Enzymes

It doesn’t matter if you’re eating the most jam-packed salad or the most superfood infused smoothie in the world, if you can’t break it down properly you’re not going to get all those incredible nutrients. When your gut isn’t functioning optimally, you might not have the digestive enzymes to break down the food your eating. That’s when these boys come in. By incorporating digestive enzyme supplements into your diet it can help you break down fats, carbohydrates and proteins that will help you get the most out of your food.

7.) Test it, don’t guess it

You’ve changed your diet, checked your products, ruled out other things and your acne is still hanging around. It’s time to do some tests. Everyone has a unique individual gut composition so doing a generalised prescription of probiotics or dietary changes can make things worse depending on what is going on inside… or more like who is living inside. You might find you have an overgrowth of pathogenic bacteria or a lack of diversity that is contributing to an unhappy gut and acne.

Take it from me, if I didn’t get my gut tested, i never would have found out how messed up my gut was, and most importantly never found the missing puzzle piece to my acne. It’s important to know EXACTLY what’s living in there. Seek help through a practitioner you trust to run some gut specific tests and help you with the treatment protocol.

8.) Support your Great Wall (ie your gut lining):

Slippery Elm, L-Glutamine, aloe vera, milk thistle and omega-3 fatty acids are just some of the supplements that can help reduce inflammation, support and repair the lining of the gut. Drinking meat stocks, the liquid gold made from cooking cartilaginous meats in water for a few hours, also helps heal and seal the lining. Note this is different to the long-cooked bone broths and is more healing when you gut needs some serious love.

So despite what Proactive commercials tell you, managing acne is not as easy as choosing the right skin products. To truly heal acne, it takes an inside-out approach that begins by looking at your gut. Because if the gut’s not functioning properly, your whole body isn’t – especially your skin.


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