If you’ve ever noticed that your skin seems to flare after periods of stress, illness, or changes in your diet, you’re not imagining it.

Researchers are increasingly exploring the gut-skin axis: the complex communication network between the digestive system, immune system, and skin. While gut health isn’t the sole cause of skin conditions like acne, eczema, or rosacea, growing evidence suggests that the gut microbiome may influence inflammation, immune function, and skin health.¹

Here’s what the science says about the connection.

What Is the Gut-Skin Axis?

Your gut is home to trillions of microorganisms collectively known as the gut microbiome. These bacteria, viruses, and fungi help digest food, produce beneficial compounds, regulate the immune system, and support the intestinal barrier.²

Because approximately 70% of the body’s immune cells reside within the gastrointestinal tract, changes in the gut microbiome can influence inflammation throughout the body, including the skin.³

This two-way relationship is known as the gut-skin axis.

Can Poor Gut Health Cause Acne?

Acne is a multifactorial condition influenced by hormones, genetics, inflammation, and the skin microbiome. However, researchers have also found differences in the gut microbiome of people with acne compared with those without.⁴

Some studies suggest that reduced microbial diversity and lower levels of beneficial bacteria may contribute to systemic inflammation, potentially influencing acne severity.⁴˒⁵

While improving gut health alone is unlikely to “cure” acne, maintaining a healthy microbiome may complement other evidence-based treatment approaches.

What About Eczema?

The relationship between the gut microbiome and eczema (atopic dermatitis) is among the best studied.

Research suggests that individuals with eczema often have altered gut microbial diversity, particularly early in life.⁶ These changes may affect immune system development and inflammatory responses.

Several systematic reviews have found that certain probiotic strains may modestly improve eczema symptoms in some individuals, although results vary depending on the strain, dose, and patient population.⁷

More research is needed before probiotics can be universally recommended as a treatment.

Is There a Gut-Rosacea Connection?

Rosacea is another condition where the gut-skin axis has received increasing attention.

Studies have reported associations between rosacea and several gastrointestinal conditions, including inflammatory bowel disease, small intestinal bacterial overgrowth (SIBO), and Helicobacter pylori infection.⁸

While these associations do not prove that gut issues cause rosacea, they suggest that inflammation originating in the gut may contribute to disease activity in some individuals.

How Does the Gut Influence the Skin?

Scientists believe several mechanisms may explain the gut-skin connection:

• Regulation of immune function
• Production of anti-inflammatory compounds called short-chain fatty acids
• Maintenance of the intestinal barrier
• Communication between the gut microbiome and immune cells
• Effects on systemic inflammation²˒³

When the gut microbiome is well supported, these processes may help maintain healthy immune responses throughout the body.

Foods That Support the Gut-Skin Axis

While there is no single “skin diet,” dietary patterns that support the gut microbiome may also benefit overall skin health.

Eat More Fibre

Dietary fibre feeds beneficial gut bacteria, allowing them to produce short-chain fatty acids that help maintain gut barrier integrity and regulate inflammation.⁹

Aim to include foods such as:

• Vegetables
• Fruits
• Legumes
• Whole grains
• Nuts and seeds

Enjoy Antioxidant & Polyphenol-Rich Foods

Polyphenols are plant compounds that beneficial gut bacteria can transform into bioactive molecules.

Good sources include:¹⁰

• Berries
• Green tea
• Olive oil
• Cocoa
• Colourful vegetables

Include Omega-3-Rich Foods

Omega-3 fatty acids have well-established anti-inflammatory properties and may help support both gut and skin health. Research suggests omega-3s can influence the composition of the gut microbiome while also helping regulate inflammatory pathways involved in several skin conditions.¹³

Good sources include:

• Salmon
• Sardines
• Mackerel
• Trout
• Walnuts
• Chia seeds
• Flaxseeds

Include Fermented & Prebiotic Foods

Fermented foods naturally contain live microorganisms that may help increase microbial diversity as part of a balanced diet.¹¹

Fermented foods include:

• Yogurt with live cultures
• Kefir
• Kimchi
• Sauerkraut
• Miso

Don’t forget prebiotics.

Prebiotics are types of dietary fibre that feed beneficial gut bacteria, helping them grow and produce compounds that support gut barrier integrity and immune function. Pairing prebiotic-rich foods with fermented foods may provide complementary support for a healthy gut microbiome.¹¹

Good sources of prebiotics include:

• Garlic
• Onions
• Leeks
• Asparagus
• Jerusalem artichokes
• Green bananas
• Chicory root
• Oats

Consider Probiotics Carefully

Not all probiotics are the same.

Research suggests that specific strains may support certain skin conditions, but benefits depend on the particular microorganism being studied.¹² Rather than choosing products based on marketing claims alone, it’s best to discuss supplementation with a qualified healthcare professional.

Foods to Limit

While no single food causes skin conditions, dietary patterns high in ultra-processed foods may negatively affect the gut microbiome and promote inflammation.

Consider limiting:

• Highly processed snack foods
• Sugar-sweetened beverages
• Excess added sugars
• Highly refined carbohydrates
• Foods high in artificial additives and emulsifiers

These foods may reduce microbial diversity or alter the balance of beneficial bacteria over time. Instead, focus on a dietary pattern centered around whole, minimally processed foods rich in fibre, healthy fats, and plant compounds.¹⁴

The Bottom Line

The gut-skin axis is an exciting area of research, but it’s important to keep expectations realistic.

Current evidence suggests that gut health may influence inflammation and immune function, both of which can affect skin conditions such as acne, eczema, and rosacea. However, the microbiome is only one piece of a much larger picture that also includes genetics, hormones, skincare, environment, and lifestyle.

Supporting your gut through a fibre-rich diet, polyphenol-containing foods, fermented foods, quality sleep, stress management, and regular physical activity may benefit both your digestive health and overall wellbeing, with your skin potentially reflecting those healthy habits over time.

References (AMA)

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2. Cryan JF, O’Riordan KJ, Cowan CSM, et al. The microbiota-gut-brain axis. Physiol Rev. 2019;99(4):1877-2013. doi:10.1152/physrev.00018.2018
3. Belkaid Y, Hand TW. Role of the microbiota in immunity and inflammation. Cell. 2014;157(1):121-141. doi:10.1016/j.cell.2014.03.011
4. Deng Y, Wang H, Zhou J, Mou Y, Wang G, Xiong X. Patients with acne vulgaris have a distinct gut microbiota in comparison with healthy controls. Acta Derm Venereol. 2018;98(8):783-790. doi:10.2340/00015555-2968
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7. Huang R, Ning H, Shen M, Li J, Zhang J, Chen X. Probiotics for the treatment of atopic dermatitis in children: a systematic review and meta-analysis. Front Cell Infect Microbiol. 2017;7:392. doi:10.3389/fcimb.2017.00392
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10. Del Rio D, Rodriguez-Mateos A, Spencer JPE, Tognolini M, Borges G, Crozier A. Dietary polyphenolics in human health. Antioxid Redox Signal. 2013;18(14):1818-1892. doi:10.1089/ars.2012.4581
11. Marco ML, Sanders ME, Gänzle M, et al. The International Scientific Association for Probiotics and Prebiotics consensus statement on fermented foods. Nat Rev Gastroenterol Hepatol. 2021;18(3):196-208. doi:10.1038/s41575-020-00390-5
12. Rather IA, Bajpai VK, Kumar S, et al. Probiotics and atopic dermatitis: an overview. Front Microbiol. 2016;7:507. doi:10.3389/fmicb.2016.00507
13. Calder PC. Omega-3 fatty acids and inflammatory processes: from molecules to man. Biochem Soc Trans. 2017;45(5):1105-1115.
14. Zinöcker MK, Lindseth IA. The Western diet-microbiome-host interaction and its role in metabolic disease. Nutrients. 2018;10(3):365.