Gut health is big business. As more researchers uncover links between gut health and a range of physical and mental diseases, this wellness sector is expected to continue its rapid growth.
According to data from the International Probiotics Association (IPA), the probiotic supplements market was valued at $9 billion in 2023 and is projected to grow at a compound annual rate of 7%.
One particularly compelling area of research is the bidirectional relationship between the gut microbiome and the skin—also known as the gut-skin axis.
Skin as a ‘mirror’ of internal health
The skin is the body’s largest organ and often described by dermatologists as a ‘mirror’ of internal health. Conditions such as acne, eczema, psoriasis and rosacea are frequently linked to underlying internal issues that must be addressed. Indeed, there is an ever-growing body of clinical evidence connecting gut microbiome imbalances to the development of skin disorders.
Climate change and increased levels of stress in recent years are also influencing this dynamic.
At the recent Aesthetic & Anti-Aging Medicine World Congress in Monaco (AMWC), Professor Peter C. Konturek, a gastroenterologist from Friedrich Schiller University Jena in Germany, discussed the impact of climate change on health—particularly gut health—stating that he is witnessing “more and more diseases caused by climate change.”
He emphasized the environment’s effect on the digestive microbiota, even likening the gut microbiome to an additional organ that is “very sensitive to these changes.”
Professor Konturek explained that many of these diseases are due to intestinal dysbiosis—the quantitative and qualitative changes in gut microbiota—which also extend to aging, not just disease.
“We have evidence that the aging process may also be accelerated by changes in the microbiota due to climate shifts,” he shared.
A ‘bidirectional relationship’ between skin and gut
Recent research published in the European Journal of Allergy & Clinical Immunology explored the intersection of diet, gut health and skin microbiota. The study described “a bidirectional relationship where nutrients affect microbial composition, influencing systemic inflammation and skin conditions.”
The gut-skin axis is inherently complex, and part of a broader “exposome”—a set of internal and external environmental factors that create a ‘perfect storm’ for the onset of skin diseases.
According to Dr. Chris Callewaert, senior post-doctoral researcher at the Center for Microbial Ecology and Technology at Ghent University and one of the co-authors of the study, many of these influences are within an individual’s control.
“The diet you consume, the hygiene habits you choose, the products you buy that you get on your skin, the sedentary/active lifestyle, the sleep you get —these are influences coming from inside our body that also steer the microbiome for a large part,” he said. “All of these factors are part of the ‘exposome’, part of the epigenetics, that determine how and if we get autoinflammatory diseases and how our immune system is trained.”
He added that this is “the main reason why in Western society we all have some form of autoinflammatory pathology (be it acne or cardiovascular diseases or cancer) and why people living a traditional hunter-gatherer lifestyle never have any cancer, acne, eczema or stress.”
Skin diseases and the gut microbiome
Acne, common among teenagers and increasingly affecting adults in their 30s and 40s, is caused by clogged pores and the bacteria Cutibacterium acnes. High-sugar, high-fat diets exacerbate acne by increasing sebum production and fostering bacterial overgrowth.
Eczema (atopic dermatitis) results in itchy, inflamed skin patches and can be triggered by food or environmental allergens. Research shows individuals with eczema have lower numbers of Bacteroidetes and Bifidobacteria, which are bacteria that work to protect the intestines against the colonization of pathogens. They also tend to have an overgrowth of Staphylococcus aureus, which contributes to skin dryness and inflammation.
A study in the Journal of the American Academy of Dermatology found a significant link between the autoimmune gut disorder celiac disease and eczema. This was not just in the case of the eczema sufferer but also notable between mothers and their children.
Psoriasis, another autoimmune disease, causes red, scaly patches. People with this condition tend to have a weakened skin barrier and an overactive immune response. It is often linked to gut dysbiosis and ‘leaky gut’, and there is also a correlation between people with psoriasis developing gut diseases like inflammatory bowel disease or celiac disease.
Rosacea, characterized by facial redness and pustules, has been linked to H. pylori infection or ‘SIBO’ (a type of bacterial overgrowth), according to research into the link between digestion and the skin issue.
Autoimmune diseases and skin conditions
Studies show that individuals with lupus, a systemic autoimmune disease that causes skin rashes and inflammation, tend to have distinctly different gut microbiomes compared to people without the autoimmune condition.
Similarly, people with vitiligo, an autoimmune disorder causing pigment loss due to melanocyte destruction, also display unique gut microbiome compositions.
There also appears to be a connection between gut microbiota and general skin aging. Research in Frontiers in Cellular & Infection Microbiology highlighted GABA—a molecule primarily produced in the gut—as playing a key role in collagen production and skin elasticity.
Not just skin, hair too
The gut-skin axis also appears to extend to the scalp and hair health.
Researchers in Spain recently discovered that a combination of probiotic strains of Lactiplantibacillus reduces gradual hair loss in people with androgenetic alopecia (AGA).
The study, which was conducted by biotech company Darwin Bioprospecting Excellence and published in the journal Nutrients, assessed the effect of a probiotic blend of Lactiplantibacillus strains comprising L. plantarum DCn_07, L. plantarum DCn_06, and L. pentosus DCn1_05 or placebo on 136 individuals with AGA over 16 weeks.
The probiotic-treated group exhibited a significantly higher abundance of Lactobacillus and demonstrated a notable reduction in hair shedding, as well as an increase in hair growth.
Results “emphasize the importance of gut lactobacilli in the treatment of alopecia” according to the authors.
Innovation in gut-skin axis skin care
As Dionne Officer, beauty and personal care analyst at Mintel, points out, innovation is lagging behind demand in addressing skin issues linked to gut health.
“Experiences of skin conditions and allergies are relatively high and expected to rise, driven by climate change, but innovation is limited—with ample room for NPD [new product development],” she noted.
Despite compelling links between gut dysbiosis and skin diseases, most microbiome innovation in beauty has focused on topical products rather than ingestible solutions that support gut health.
French brand Galinée, now owned by Shiseido, was an early adopter in this space. It offers a range of beauty and personal care products targeting the skin, gut, oral and vaginal microbiome. Its Calm & Microbiome, which includes red algae and psychobiotic probiotics, is designed to soothe the gut and the mind, and thereby the skin.
UK-based brand You’re Looking Well also champions an inside-out approach. It offers morning and evening ingestible supplements for gut health, paired with topical products for skin care.
“The timing of the results is phased—more immediate benefits like skin hydration and sleep quality, with longer-term benefits for gut health,” said founders Joe Bloomfield and Anthony Plom.
Their Live Bacteria Blend—formulated by dietitian Sophie Medlin and gut health expert Professor Glenn Gibson—contains Lactobacillus paracasei Lpc-37, Bifidobacterium lactis BI-04, and B. lactis HN019 in a delayed-release capsule to ensure viability in the gut. The blend reportedly works together to support healthier skin, improve gut health and offer cognitive function benefits.
Meanwhile, Hollywood dermatologist Dr. Simon Ourian has expanded from AI-powered skincare into wellness supplements with his Daily Ritual line. These customized supplements use AI to analyze wellness profiles and target concerns such as mood, energy, gut health and skin vitality.
“All play a very critical role in how your skin looks and feels,” he said. “Your skin is basically the mirror of what goes on inside your life, and what I see for the future is a shift towards, more, integrated approach to products that probably continue to be scientifically advanced but that also work in synergy with lifestyle choices and changes.”
Brands in the supplement space are also capitalizing on skin-gut health claims. For example, Symprove, a patented water-based probiotic solution, claims to deliver over 10 billion colony-forming units per shot—one of its benefits being improved skin through enhanced gut health.
