The Skin-Gut Connection

The skin microbiome plays a vital role in maintaining overall health by supporting interactions of the body’s largest organ with the immune system. It maintains a slightly acidic pH that inhibits harmful pathogens, producing antimicrobial substances and acting as a protective barrier.

“The microbiome also regulates the immune system by training it to distinguish between harmful and harmless microbes, reducing the risk of overreactions that can lead to conditions like eczema or psoriasis,” explains Farnoush Salimy, ND, of Vancouver’s Vitalia Health Care.

“Additionally, a balanced skin microbiome promotes wound healing by reducing inflammation and stimulating cell regeneration. Certain skin microbes contribute to hydration and barrier function by breaking down lipids and producing beneficial compounds, such as vitamin B derivatives.

“Maintaining a balanced microbiome is essential to prevent dysbiosis―an imbalance in gut bacteria―which can disrupt these functions and lead to skin and systemic health issues. Factors like diet, hygiene practices, and environmental exposures can influence this balance, underscoring the importance of a holistic approach to skin health.”

The gut-skin axis

The gut and skin are connected through the gut-skin axis, a bidirectional relationship between the gut microbiome and skin health. A healthy gut microbiome produces short-chain fatty acids like butyrate, which reduce inflammation and help prevent skin conditions such as acne, eczema, and psoriasis.

“Conversely,” Salimy says, “gut dysbiosis can increase intestinal permeability, often called ‘leaky gut.’ This allows toxins and inflammatory molecules to enter the bloodstream, triggering skin inflammation and exacerbating issues like autoimmune disease or allergies.”

Diet’s important role

Diet plays a crucial role in maintaining a balanced gut microbiome. Consuming prebiotics (found in high-fibre foods like fruits and vegetables) and probiotics (found in fermented foods like yogurt, kefir, kimchi, and sauerkraut) nourishes beneficial gut bacteria, supporting skin health.

On the other hand, diets high in processed foods, sugar, or dairy may disrupt gut balance and worsen skin conditions. “Adopting a nutrient-rich, whole foods-based diet can promote a healthy gut microbiome, reduce inflammation, and enhance skin clarity and resilience,” Salimy says.

Clean, but not too clean

Overshowering and using harsh soaps can interfere with the skin’s microbial balance by stripping away beneficial microbes and compromising the skin’s natural protective barrier. “Harsh soaps, often alkaline or containing antimicrobial agents, can raise skin pH, killing these beneficial microbes and reducing microbial diversity,” Salimy says.

“Overshowering, especially with hot water, exacerbates this by washing away natural oils and lipids, which are essential for maintaining the skin’s barrier and microbial habitat. This loss makes the skin more permeable to irritants, allergens, and pathogens, increasing the risk of inflammation, infections, and conditions like acne or dryness.

“As beneficial microbes diminish, opportunistic pathogens can thrive, further disrupting skin health,” Salimy adds. “Using gentle, pH-balanced cleansers and limiting shower frequency can help preserve the skin’s microbiome and protective functions.”

Impacts of microbiome imbalance

A disrupted skin microbiome can greatly impact skin health, notably by contributing to acne and dryness. An imbalance in the microbiome can lead to the overgrowth of Cutibacterium acnes, a bacterium that triggers inflammation and exacerbates acne, Salimy explains. “Additionally, reduced populations of anti-inflammatory bacteria weaken the skin’s barrier, increasing inflammation and worsening conditions like eczema.

“Beneficial microbes produce moisturizing compounds, such as lipids, that maintain the skin’s hydration and integrity. Disruption from harsh soaps or overshowering strips these lipids, increasing transepidermal water loss and leading to dry, cracked, or irritated skin, which is more vulnerable to environmental damage, allergens, and irritants.”

Staying clean without compromising your microbiome

There are several ways to achieve a balanced hygiene routine that supports the skin and gut.

• Use gentle skincare products, such as pH-balanced (around 4.5 to 5.5), fragrance-free cleansers, and soaps with minimal surfactants to preserve beneficial skin microbes.
• Avoid antimicrobial soaps unless medically necessary, as they can disrupt the microbial diversity.
• Limit showering to once daily or every other day with lukewarm water for five to 10 minutes to avoid stripping natural oils and microbes, which maintain the skin’s barrier.
• Limit exfoliation to one to two times per week with gentle chemical exfoliants, such as lactic acids, to avoid disrupting the skin’s microbial diversity.
• Apply moisturizer post-shower to lock in hydration and support the skin’s lipid barrier, and use broad-spectrum sunscreen daily to protect against UV damage.

This article was originally published in the November 2025 issue of alive magazine.