June/July 2021 Issue

Probiotics: Can Probiotics Clear Up Common Skin Disorders?
By Sherry Coleman Collins, MS, RDN, LD
Today’s Dietitian
Vol. 23, No. 6, P. 18

People who struggle with common chronic skin conditions may find relief using new and innovative treatments that incorporate probiotics. In fact, there’s emerging research that suggests probiotics may provide significant relief without unwanted side effects as an adjunct or stand-alone therapy. In this article, Today’s Dietitian evaluates the research on the use and potential efficacy of probiotics in the treatment of atopic dermatitis (eczema), psoriasis, and acne—three of the most common chronic skin conditions.

The skin is one of the most neglected organs in the human body yet serves an incredibly important role as a barrier and system of protection against pathogens, allergens, and parasites. Moreover, it’s one of the first things people see when they look at a person. From a cosmetic and medical perspective, having clear, healthy, and intact skin is important. The use of naturally probiotic-containing foods, such as yogurt, and clay, or dirt, has long been part of natural approaches to skin care, including for bathing and facial application.

Recent research has shown that the microbiome has a significant impact on human health in many areas, including skin health. The microbiome includes all of the microbes that live on and inside the body.1 Differences in the colonization of microbes in the gut and on the skin has been found in those with chronic skin conditions, including atopic dermatitis, psoriasis, and acne.2

As a topical treatment, probiotics can be added to lotions or emollients that are applied onto the skin. Several brands containing probiotics currently are sold and claim benefit. Probiotics may improve skin health through competition by potentially increasing good bacteria (thereby reducing harmful bacteria), by acting in an antibacterial capacity or modifying the skin’s pH, and by stimulating the natural production of ceramides and other beneficial compounds in the skin via lactic acid.3

Dysbiosis in the gut could impact skin health. The specific interactions between the gut microbiota and skin are referred to as the “gut-skin axis,” which is thought to be an important modulator of immune health.4 Currently, a variety of dietary supplements are being marketed with claims of benefiting skin health.

Atopic Dermatitis
Atopic dermatitis (AD), also called eczema, is a chronic inflammatory disease of the skin caused by a combination of genetic, environmental, and immunologic factors, and is estimated to affect up to 20% of the population.2,5 AD varies in severity and can lead to itchy, weeping, excoriated skin that can be difficult to treat. It also may lead to skin infections and predisposes infants to the development of food allergies. While most often diagnosed in the first year of life, eczema also can affect adults. Typical treatment includes a skin care regimen to keep broken skin clean and moisturized, and topical steroids for inflammation.

Manipulating the gut microbiome in AD has shown some benefit for prevention and symptom reduction. Research shows that individuals with AD have reduced skin bacteria diversity but an increase in fungal diversity compared with those without AD. Supplementation with probiotics containing Lactobacillus in the maternal diet during the last trimester and breast-feeding reduced the risk of AD in infants; the use of Lactobacillus alone and combined with species of Bifidobacterium have resulted in improvement of symptoms in studies involving children aged 1 to 18. Some studies have shown benefit with administering both Lactobacillus and Bifidobacterium in adults. However, the studies to date have been small and aren’t yet generalizable.2

The topical application of probiotics in research studies also has shown some promise in countering the effect of pathogenic bacteria that have been implicated in causing flares (ie, exacerbation of inflammation and itching) associated with AD.5 However, studies have been small, and there has been significant heterogeneity between studies, including in the strains of bacteria used.

Believed to be an immune disease, psoriasis is characterized by patches of dry, itchy, and red skin often found on the knees, elbows, and upper body, including the scalp. It’s difficult to treat and poorly understood, but genetic and environmental factors both seem to contribute.6 Psoriasis sometimes is accompanied by psoriatic arthritis, which causes swelling and pain in the joints.

In addition to having a different composition of bacteria dominant on the skin in affected areas, people with psoriasis also often have accompanying gastrointestinal conditions, such as inflammatory bowel disease.7 Because research has shown probiotics to be of potential benefit for people with inflammatory bowel disease and researchers are recognizing the role of the gut-skin axis, it’s theorized that modification of gut microbiota has potential in helping ameliorate psoriasis symptoms. However, limited studies have reviewed this potential to date and, although there have been positive outcomes, there was great heterogeneity among study designs, making it difficult to draw conclusions.

Acne is a multifactorial condition that occurs when the hair follicles in the skin become clogged by oil and dead skin cells. Untreated, these follicles produce whiteheads or blackheads and can become inflamed, resulting in large red bumps. Most often occurring in the teen years and sometimes well into adulthood, acne can be a source of physical and emotional discomfort.

Topical application of multiple strains of lactic acid–producing bacteria has shown promising benefit in reducing inflammation and redness in subjects with acne. Researchers have discovered that this treatment may help by inducing anti-inflammatory activity, perhaps due to the antimicrobial action associated with inhibiting the growth and colonization of pathogenic microbes, including the harmful Propionibacterium acnes strain.8

Bottom Line
Skin health is an important part of overall well-being. There isn’t enough research to advise clients and patients on exactly which probiotic strains and doses and in what form (eg, oral supplementation or topical application) may produce significant benefits. In addition, there’s some concern that topical probiotic use may promote antibiotic resistance and risk of allergic reactions.9 Still, low-risk interventions such as using yogurt for natural facemasks may be an easy way to calm inflamed skin, although there’s still potential for allergic reactions.

It’s clear that there’s an important connection between skin health and gut health. Recommending evidence-based interventions such as increasing fiber in the diet and including food sources of probiotics and prebiotics may help shift gut microbiota toward a more healthful profile. Importantly, however, there’s no defined optimal gut or skin microbiome. Skin health is improved with a diet rich in vitamins and minerals, and when individuals are properly hydrated. Whether these recommendations ultimately improve AD, psoriasis, or acne, there are many other potential benefits for clients. And dietitians can be part of the health care team to help patients look and feel better in their skin.

— Sherry Coleman Collins, MS, RDN, LD, is president of Southern Fried Nutrition Services in Atlanta, specializing in food allergies and sensitivities, digestive disorders, and nutrition communications. Find her on Twitter, Instagram, and Facebook as @DietitianSherry and at southernfriednutrition.com.

1. Amon P, Sanderson I. What is the microbiome? Arch Dis Child Educ Pract Ed. 2017;102(5):257-260.

2. Rusu E, Enache G, Cursaru R, et al. Prebiotics and probiotics in atopic dermatitis. Exp Ther Med. 2019;18(2):926-931.

3. Cinque B, La Torre C, Melchiorre E, et al. Use of probiotics for dermal applications. In: Liong MT, ed. Probiotics: Biology, Genetics and Health Aspects. New York, NY: Springer; 2011:221-242.

4. Salem I, Ramser A, Isham N, Ghannoum MA. The gut microbiome as a major regulator of the gut-skin axis. Front Microbiol. 2018;9:1459.

5. Ambrożej D, Kunkiel K, Dumycz K, Feleszko W. The use of probiotics and bacteria-derived preparations in topical treatment of atopic dermatitis — a systematic review. J Allergy Clin Immunol Pract. 2021;9(1):570-575.e2.

6. Benhadou F, Mintoff D, Schnebert B, Thio HB. Psoriasis and microbiota: a systematic review. Diseases. 2018;6(2):47.

7. Szántó M, Dózsa A, Antal D, Szabó K, Kemény L, Bai P. Targeting the gut-skin axis — probiotics as new tools for skin disorder management? Exp Dermatol. 2019;28(11):1210-1218.

8. França K. Topical probiotics in dermatological therapy and skincare: a concise review. Dermatol Ther (Heidelb). 2021;11(1):71-77.

9. Lee GR, Maarouf M, Hendricks AJ, Lee DE, Shi VY. Topical probiotics: the unknowns behind their rising popularity. Derm Online J. 2019;25(5):13030/qt2v83r5wk.