The microbiome, or collection of friendly bacteria that resides in your gut, has been a buzzy topic in the health world for a while now. Research continues to uncover the many ways this collection of microorganisms impacts health. But what not everyone may know is that microbes don’t just reside in your digestive tract. Your body’s largest organ, your skin, is also host to millions of microorganisms that play a similar role to those in your gut, protecting your body against pathogens and influencing immunity and inflammation.
There’s a lot that is still unknown about the skin microbiome, but it is believed that it plays a key role in inflammatory skin diseases, such as atopic dermatitis, psoriasis, acne, and rosacea, and possibly other systemic diseases as well. Researchers and scientists are studying what a healthy microbiome looks like, exactly, and what you can do to keep yours balanced and strong.
What Is the Skin Microbiome?
“The skin microbiome is the community of bacteria, fungi, and viruses — and some people include mites — that reside on and in our skin,” said Heidi H. Kong, MD, a board-certified dermatologist with the National Institute of Arthritis and Musculoskeletal and Skin Diseases who researches the human microbiome and inflammatory skin diseases.
Researchers are still exploring exactly how the skin microbiome works. These “friendly” bacteria may help control the growth of other, harmful microbes. There’s still a lot that is not clear, but it appears that a healthy microbiome should be balanced and diverse, according to research published in the International Journal of Cosmetic Science in November 2019.
Everyone’s skin flora — the specific collection of microorganisms living on it — is unique, and even from place to place on your own body, your skin microbiome varies. Researchers who study skin conditions such as atopic dermatitis, psoriasis, and acne vulgaris have uncovered imbalances in their skin microbiomes.
What Are the Benefits of a Healthy Skin Microbiome?
“A healthy microbiome keeps unhealthy bacteria and fungi away,” says Leslie Baumann MD, a board-certified dermatologist, author, and researcher in Miami. There is some evidence, including the previously mentioned research published in the International Journal of Cosmetic Science, that imbalances in the skin microbiota can result in cellular inflammation, which has been linked to many chronic diseases. Unhealthy bacteria and fungi on the skin can cause inflammation and activate the immune system, says Dr. Baumann.
This could possibly even contribute to inflammatory diseases such as type 2 diabetes.
The skin microbiome is also thought to play a role in immunity by helping recognize and block disease-causing pathogens, according to a review published in January 2018 in Nature Reviews: Microbiology.
Studies have found that people with immune deficiencies have different microbiomes tan healthy volunteers.
“That tells us that the immune system is important in shaping the microbiome,” says Dr. Kong.
There may also be connections between the skin microbiome and various skin diseases and conditions:
- Acne Baumann says that the bacteria Cutibacterium acnes could build up on the skin and lead to acne. And research published in the American Journal of Clinical Dermatology in September 2020 indicated that other types of bacteria may be associated with acne as well.
- Atopic Dermatitis (Eczema) Certain types of Staphylococcus bacteria are associated with eczema flares, but researchers haven’t identified cause and effect. “In eczema, you do see a different microbiome,” Kong says. People with atopic dermatitis have high levels of Staphylococcus aureus, according to research published in Annals of Allergy, Asthma, and Immunology in March 2019.
- Rosacea “Rosacea is most likely affected by the skin microbiome, too, but we do not know what organisms play a role,” says Baumann.
- Psoriasis There may be a link between the skin microbiome and psoriasis, but more research is needed, according to a review published in Clinics in Dermatology in March 2019.
How Are the Gut and Skin Microbiomes Connected?
More research is needed to tease out the connections between the gut and skin microbiomes. The communities of microorganisms living on the skin and in the gut are fairly different, says Kong. It’s not clear whether changing the gut microbiome changes the skin microbiome.
There is one known connection: Some oral probiotics that affect the gut microbiome might improve inflammatory skin diseases like eczema.
“We do not yet know which [probiotics] are best for which diseases, but I bet in the next two years, we will learn a lot,” says Baumann.
Researchers are exploring connections between the gut and the skin, or the gut-skin axis. They are examining how it relates to skin conditions such as psoriasis, atopic dermatitis, rosacea, acne, aging, and skin wounds, and whether changes in the diet might help improve symptoms, according to a Clinics in Dermatology overview published in September 2021.
What Damages the Skin Microbiome?
Your skin microbiome is relatively stable and resilient. But Baumann says that environmental factors, beauty products and cleansers, and poor diet could harm it.
Probiotic skincare, which has become increasingly popular, can also damage it by putting excessive amounts of one type of organism on the skin. “Diversity is key. Having too much of one type of bug on the skin is a bad thing, no matter how ‘good’ the bacteria is,” says Baumann.
Oral antibiotics have also been known to kill healthy bacteria on the skin. Healthy people who took antibiotics developed antibiotic-resistant bacteria that were detectable on their skin a year later.
“I would not say we shouldn’t use antibiotics. They are important — they save lives and treat infections,” Kong says. But she recommends considering whether you need antibiotics, making sure you take them for the appropriate duration, and choosing a targeted antibiotic.
How to Keep Your Skin Microbiome Healthy
More research is needed to uncover which aspects of the skin microbiome support skin health and how to keep them healthy. “People like this idea of, if you have a bad bacteria, you just need to replace it with a good bacteria, and then we’re going to solve the problem. Well, we often don’t really know how bacteria are interacting with each other,” Kong says.
Experts say that it is probably too early to trust products that claim to support or improve your skin microbiome. Even on one person’s skin, the microbiome varies from place to place, so it can be a challenge for products to target skin flora. For example, research published in the Journal of the American Society for Microbiology in July 2019 found that certain bacteria in more oily places such as the forehead and more diverse skin flora in drier areas such as the forearm.
“We just do not know enough yet. It drives me crazy when companies take the science and mislead people,” Baumann says. “In a few years, when these products really can work, no one will believe it.”
To help protect your skin microbiome, you can choose gentle cleansers and skincare products. “If it’s too abrasive, you’re setting your skin up to be a good environment for pathogens or bacteria that like to attach to a barrier that’s not intact,” says Kong. “And you typically don’t need something that’s antimicrobial, unless it’s for hand hygiene.”
What Can an At-Home Skin Microbiome Test Kit Tell You?
Companies have started selling at-home kits purporting to tell you what types of microbes live on your skin, usually with the goal of recommending skincare products.
For such at-home microbiome tests to be effective, Kong says they have to factor in how frequently you bathe or shower, since that likely changes the concentration of microbes on your skin.
Where you take a sample matters, too. “We know from our studies that the microbiome on your forehead is different from your hands, parts of your arm, or behind your ear,” she says. The type of sequencing they’re doing at the lab makes a difference, too.
But even if you know what makes up your skin microbiota, there’s not much you can do with that information. “[At-home tests] are useless unless we know what organisms are best on the skin. They should be considered a research tool right now,” Baumann says.
Summary
The collection of microbes that live on your skin — bacteria, fungi, viruses, and mites — may play a role in keeping your skin healthy and controlling common skin conditions. Studying the skin microbiome is a developing area for research, and more studies are needed to determine how certain microbes affect your health and what you can do to help keep them healthy.
Author: Stephanie Thurrott Medically Reviewed by Mohiba Tareen, MD
Date: June 10, 2022
Link: https://www.everydayhealth.com/skin-beauty/everything-you-need-to-know-about-the-skin-microbiome/
Nutrigenomics Institute is not responsible for the comments and opinions included in this article
