Gut Health for Glowing Skin: The Science Behind the Gut-Skin Connection

As a functional medicine practitioner, I see skin issues all the time. Breakouts, eczema, rosacea, psoriasis, dry skin, irritated skin, sensitive skin, rapidly aging skin… to name just a few.

I think of skin disruptions like a check engine light. They’re a signal that something is going on beneath the surface– and a mirror of your internal environment.

And when I go upstream to find the root cause, I almost always find a gut problem there.

Let’s take a look at the science behind the gut-skin connection, how the gut microbiome and skin microbiome affect each other, and how to heal your skin and gut holistically.

The Gut-Skin Axis

The gut-skin axis refers to the bidirectional communication between the gut and the skin. (1)

You may be familiar with the gut-brain axis or gut-brain connection– the gut has an intimate, two-way relationship like that with every organ in the body. And although we often think of the skin as somehow separate from the body, it is in fact our largest organ, making up about 10% of our total body weight.

So, inflammation, imbalances, and other issues in the gut can influence the health of your skin, and vice versa. And as I mentioned above, you can think of your skin like a check engine light – it’s one of the first places where we can see that something isn’t quite right internally.

Skin disorders like acne, rosacea, psoriasis, and eczema almost always have roots in systemic inflammation, immune dysregulation, and/or gut dysfunction. (2) In fact, I’d argue almost all skin issues fall somewhere on the inflammation-autoimmune spectrum (at least inflammatory, if not autoimmune).

Your Gut and Skin Microbiomes

Just like the gut, the skin has its own microbiome– a vast ecosystem consisting of trillions of bacteria, fungi, and other microorganisms. These microbes work together to perform essential functions related to immunity, protection from external harm, detoxification, nutrient absorption, and overall health.

And, like with the gut, the skin microbiome can be in a state of dysbiosis– an imbalance between beneficial and harmful microbes, which can lead to inflammation and chronic skin issues.

When dysbiosis occurs, the skin’s protective barrier can become compromised, allowing moisture to escape and irritants, allergens, toxins, and pathogens to seep in. This triggers the immune system to act, which can result in reactive, sensitive, or inflamed skin– and inflammation throughout the body. (3) Skin damage can also disrupt the gut microbiome. (4)

Leaky Gut and Leaky Skin

Another important parallel between the gut and the skin relates to their protective barriers. We’ll start with the gut: a healthy gut lining works to absorb nutrients from food, while keeping substances like toxins and undigested food particles from entering the bloodstream.

The lining of the gut can be weakened by things like chronic stress, processed foods, alcohol, certain kinds of medications, and infections. This results in increased intestinal permeability (better known as leaky gut).

Particles like undigested food and toxins essentially “leak” out into the bloodstream, triggering immune system activation and inflammation.

This inflammation can show up just about anywhere, including the brain, the joints, the thyroid, or, of course, the skin.

Our skin also has a protective barrier, and this barrier can also become “leaky”. When the skin microbiome is disrupted and the barrier is damaged, irritants can similarly get through and trigger immune responses and inflammation– which may then manifest as rashes, breakouts, or inflammatory conditions like psoriasis.

Leaky gut and leaky skin are closely related: when one barrier is compromised, the other often is, too. (5)

Conditions Linked to the Gut-Skin Connection

I would venture to say that no skin condition exists that can’t be connected to the gut (at least in some cases). But let’s take a look at a few key examples based on available research to date:

• Acne is tied to overgrowth of the bacterial species Cutibacterium acnes and an increase in sebum production, both of which are influenced by diet, hormones, and gut health. Gut-disruptive high sugar diets and low microbial diversity can both worsen acne. (6)
• Rosacea is significantly more common in people with SIBO (small intestinal bacterial overgrowth). (7) SIBO has been found in close to half of SIBO patients, and is 10x more prevalent in rosacea patients than in healthy controls.
• Eczema (atopic dermatitis) is associated with both gut and skin dysbiosis, including overgrowth of Staphylococcus aureus and reduced microbial diversity. (8, 9)
• Psoriasis, an autoimmune skin disease, is linked to increased gut permeability and decreased microbial diversity. Up to 10% of people with IBD (inflammatory bowel disease) also have psoriasis. (10)
• Vitiligo, lupus, and alopecia all show distinct microbiome patterns, both in the gut and on the skin. (11 - 13)
• Even skin aging is affected. Oxidative stress and reduced microbial diversity can accelerate the effects of aging on the skin. (14)

In short, where there’s skin inflammation, there’s usually gut inflammation (and vice versa).

Root Causes to Investigate

One of my main jobs as a functional medicine practitioner is to investigate the root cause of my patients’ symptoms and health concerns. Knowing that something is wrong within the gut and the skin isn’t enough– I have to figure out where these imbalances or disruptions are coming from.

In most cases, there are multiple contributing factors, which we can untangle and work to resolve together.

Here are a few things I look for when someone comes to me with chronic skin issues: 

• Leaky gut
• Gut dysbiosis, including:
• SIBO (small intestinal bacterial overgrowth)
• Yeast overgrowth (like candida)
• Food sensitivities
• Past unresolved trauma or chronic stress
• Environmental toxins

Healing Through the Gut-Skin Axis

Now that you know a bit more about the science behind the gut-skin connection, let’s talk about how we can use that knowledge to heal both the gastrointestinal tract and the skin.

Start With Food

Everything you eat either fuels inflammation or fights it. For glowing skin, you’ll always want to start from a place of eliminating known inflammatory foods like sugar, refined carbohydrates, processed foods, and industrial seed oils.

As a next step, I always recommend following an elimination diet to determine which foods trigger inflammation for you. We’re all different, and a food that is medicine to one person is often triggering to another.

While there’s basically no limit to the variety of foods someone might be sensitive to, there are definitely a few common dietary culprits that I would investigate first. These may include:

• Grains (both gluten-containing and non-gluten)
• Dairy
• Nightshades
• Eggs
• Beans and legumes
• Nuts

Next, you’ll want to emphasize gut and skin supportive foods and drinks, including: 

• Whole, nutrient-dense foods
• Healthy fats rich in omega-3 fatty acids, like wild-caught fish, olive oil, and avocados
• Antioxidant-rich fruits and vegetables
• Hydrating foods and beverages
• Fermented foods for natural probiotics
• Prebiotic foods

I’m also a big fan of getting a lot of your powerful skincare ingredients through your diet. For example, bone broth is rich in collagen, which is essential for skin integrity and healing. And, something many people don’t know– vitamin C is one of the most important nutrients when it comes to producing our own collagen, so I recommend consuming plenty of citrus fruits and other sources of vitamin C.

You can also get true retinol from vitamin A in healthy animal fats like wild-caught fish and grass-fed beef (as well as other fat-soluble vitamins like D and K2, all of which are essential for healthy skin). True retinol from these sources is more bioavailable than the plant source of vitamin A, beta-carotene, which the body has to convert.

Support Your Gut Microbiome

Probably no surprise here– to get your glow back, you’ll need to heal and nurture your gut microbiota. Here are a few simple ways to encourage better microbial balance and the growth of healthy gut bacteria:

• Take a probiotic supplement (you can find mine here)
• Eat prebiotic foods like onions, garlic, asparagus, and artichokes– if you tolerate them well
• Consider postbiotics (the beneficial compounds gut microbes produce, like short-chain fatty acids or SCFAs)
• Avoid unnecessary antibiotics and NSAIDs
• Avoid or limit alcohol
• Reduce toxin exposure

Check out my complete guide to healing your gut here for more guidance.

Clean Up Your Skincare Routine

I know I’ve mostly been talking about how to heal your skin from the inside, but topical skincare matters too– a lot! What we put on our skin can either nourish or disrupt the skin microbiome, and either support or strip your skin barrier.

Look for clean, non-toxic products from brands that are transparent with their ingredients and process. You can find some of my favorites here.

Embrace Rest, Ritual, and Nervous System Regulation

I see many patients carrying past trauma or dealing with chronic stress and burnout, and these emotional wounds can manifest physically through gut dysfunction and inflammatory skin conditions.

Practices like breathwork, meditation, somatic therapy, or just spending time in nature can help to downregulate the stress response and reduce inflammation. Just find something that works for you and do it regularly– and don’t forget about the importance of sleep.

A Final Word

I’m a big advocate for taking your skin seriously. For one, I know from personal experience how much it can affect your confidence when your skin is suffering. And of course, because skin problems are usually pointing to other health problems.

Your skin is not separate from your gut… or your brain, or your hormones, or your immune system. The body doesn’t work in silos: everything is connected.

If you want more personalized support healing your gut, skin health, and overall well-being, my team and I would be happy to help. Please reach out whenever you’re ready and we will walk you through your next steps.

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