The Microbiome: An Invisible World on Your Skin

Reviewed by Dr. Rishu Gupta, MD, and Valerie George, Cosmetic Chemist

I had a lot of acne and dandruff growing up. It’s better now, but I still get occasional breakouts and flakes, usually during times of stress.

I was told that oiliness was the cause of my acne and dandruff, but it wasn’t until recently that I learned the real culprit might be the microscopic organisms that live on my skin.

Yeast and bacteria that live on our skin are linked to multiple skin disorders, including acne, dandruff, eczema, seborrheic dermatitis, and psoriasis. These microbes are found in both healthy and unhealthy skin and scalps, so I asked myself: why do some people get skin disorders while others don’t?

To answer that question, I needed to understand how the skin’s microbiome works.

So I talked to microbiome experts and dermatologists, attended hair and skin care conferences, and poured through medical journals to learn about the microbiome. In this article, you will learn what the microbiome is and the role it plays in your skin’s health.

What is the skin microbiome?

Our skin is covered in billions of bacteria, fungi, viruses, and mites. But don’t freak out! These microbes are a natural part of everyone’s skin. This ecosystem of microbes is referred to as the skin’s microbiome.

Microbes are first introduced to our skin at birth. The compositions of microbes changes overtime through exposure to different people, environments, and biologicals changes.

The composition of the microbiome also varies between people and different parts of the body. For instance, the microbiome on the scalp will have a different composition than the microbiome on the feet.

While the gut microbiome has typically been a very popular topic, the skin microbiome has had a growing body of new research. For instance, a 2023 study has shown that development of eczema and allergies may be linked to how your microbiome forms at a young age.

What does the microbiome do?

You can think of your microbiome as if it’s a city: the microbes are the people and skin is the infrastructure.

A diverse population of people with different jobs and skills leads to a highly functioning city. In return, the city provides a place for people to thrive in. The microbiome is very similar in that regard.

Most of the microbes on healthy skin are commensal or mutualistic, meaning they cause no harm or even help us. Some benefits include:

Acting as the first line of defense in fighting off pathogens (harmful microbes)
Training our immune system
Maintaining a balanced skin pH level
Breaking down nutrient compounds that our skin can use

In exchange, the microbes get to live in a habitat where they have nutrients (e.g. oil, dead skin) and the environment they need to survive.

What does a good microbiome look like?

There is no definitive answer to what a “good microbiome” looks like. However, diversity in microbial population is linked to healthier skin. A lack of diversity is linked to skin disorders.

The Yanomami tribe in the Amazon provides a fascinating case study on microbiome diversity. The Yanomami live very secluded lives apart from modern amenities, yet they exhibit one of the most diverse microbiomes ever recorded.

Interestingly, they don’t exhibit skin ailments common to western societies, such as acne and eczema. Some of their bacteria also show antibiotic resistances despite never having been exposed to synthetic antibiotics.

Their unique biomes are attributed to their exposure to the outdoors, hygienic habits, diet, and isolation. It calls into question the habits we have today, such as over cleansing with harsh soaps, and how it might impact our skin.

What can impact our skin’s microbiome?

There are both intrinsic and extrinsic factors that affect the skin’s microbiome composition.

Intrinsic factors

Age - The microbiome changes as we age due to hormonal changes and decrease in sebum production
Gender - Men and women typically have different compositions due to differences in sebum production, hormones, and lifestyles
Genetics - Numerous genetic factors, such as sebum production or skin barrier dysfunction, can affect microbial composition
Immunity - A compromised immune system is associated with disrupted microbiomes
Sleep - Lack of sleep is associated with disrupted microbiomes
Stress - Chronic stress is associated with disrupted microbiomes

Extrinsic factors

Hygiene - Over cleansing can strip the microbiome, but under cleansing may also allow harmful microbes to overproduce
Diet - balanced diets low in processed foods are associated with more diverse microbiomes
Beauty routine - harsh ingredients or microbe-feeding oils in personal care products can disrupt the microbiome
Climate - Heat, sunlight, and humidity can affect microbial composition
Pollution - Pollutants in air and water can disrupt the microbiome
Physical activity - Exercise is shown to have a positive effect on the gut microbiome, this may extend to the skin microbiome as well

What happens if the microbiome isn’t healthy?

The microbiome can be considered “unhealthy” when it becomes imbalanced - this is also called dysbiosis. in dysbiosis, opportunistic pathogens (harmful microbes) take over, leading to skin and scalp disorders such as eczema, acne, and dandruff.

For instance, Cutibacterium acnes (C. acnes) is associated with acne, Staphylococcus aureus (S. aureus) with eczema, and Malassezia furfur (M. furfur) with dandruff and fungal acne.

How these microbes trigger the skin disorders is still not fully understood.

One theory is that the fatty acids microbes leave behind after eating sebum (skin oil) irritate the skin, causing inflammation and compromising the skin barrier.

Another theory is that pathogenic microbes burrow deeper into the epidermis when the skin barrier is already damaged, causing further inflammation.

What is apparent is that a balanced microbiome can help with preventing or reducing the severity of many skin disorders.

How do you maintain a balanced microbiome?

Because there are numerous factors that can impact the microbiome, maintaining a balanced microbiome requires a diverse approach.

Skin and haircare

Look for milder hair and skincare products, such as products labeled as “hypoallergenic”
Avoid over-cleansing and excessive scrubbing
Keep the skin moisturized
Don't use excessively hot water

Lifestyle

Get proper sleep
Avoid excessive sun exposure
Avoid heavy air pollution
Use antibiotics only when necessary

Diet (this may help, but is not confirmed)

Eat foods rich in antioxidants and vitamins, such as fruits and vegetables
Eat fibrous food rich in prebiotics, such as whole grains, seeds, and beans
Eat fermented foods rich in probiotics, such as yogurt, kimchi, and kombucha

Conclusion

The microbiome plays a crucial role in the health of your skin. A balanced microbiome acts as your shield against skin disorders and requires thoughtful maintenance.

Today, the popular approach to treat skin disorders is to use products that contain antimicrobials such as benzoyl peroxide or zinc pyrthione.

While antimicrobials can help achieve short-term results, they may not be great for the long run as they also kill off good microbes that help your skin. A better approach may be to incorporate habits that help you achieve a balanced microbiome.

There is still a lot to uncover about the skin’s microbiome, but it’s providing exciting new ways to think about how we approach skincare and what healthy skin really means.

What we do at OCHRE

We’re a team who has personally experienced the challenges of acne, eczema, and dandruff, and are passionate about creating products that we love and work for us.

While we can’t control your genetics, habits, and environment, we can help keep your microbiome in balance, leading to healthier hair and skin.

Our meticulously researched hair care line is:

Microbiome balancing: 3rd party lab testing has shown that our products maintain your microbiome.
Eczema Safe: our products are accepted by the National Eczema Association.
Hypoallergenic: we exclude 1,000+ irritating or microbe feeding ingredients.
Noncomedogenic: our products won’t clog your pores.

Sources

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Chen Y, Knight R and Gallo RL (2023) Evolving approaches to profiling the microbiome in skin disease. Front. Immunol. 14:1151527. doi: 10.3389/fimmu.2023.1151527
De Pessemier B, Grine L, Debaere M, Maes A, Paetzold B, Callewaert C. Gut–Skin Axis: Current Knowledge of the Interrelationship between Microbial Dysbiosis and Skin Conditions. Microorganisms. 2021; 9(2):353.
Jose C. Clemente et al., The microbiome of uncontacted Amerindians. Sci. Adv. 1, e1500183 (2015). DOI: 10.1126/sciadv.1500183
Puce L, Hampton-Marcell J, Trabelsi K, Ammar A, Chtourou H, Boulares A, Marinelli L, Mori L, Cotellessa F, Currà A, Trompetto C, Bragazzi NL. Swimming and the human microbiome at the intersection of sports, clinical, and environmental sciences: A scoping review of the literature. Front Microbiol. 2022 Aug 3
Rapin, A, Rehbinder, EM, Macowan, M, et al. The skin microbiome in the first year of life and its association with atopic dermatitis. Allergy. 2023; 00: 1- 15. doi:10.1111/all.15671
Sibi D, Silvanose CD, Jibin VG. Role of Malassezia furfur and M. globosa in Dandruff and Seborrheic Dermatitis. J Clin Investigat Dermatol. 2023;11(1): 2
Skowron K, Bauza-Kaszewska J, Kraszewska Z, et al. Human Skin Microbiome: Impact of Intrinsic and Extrinsic Factors on Skin Microbiota. Microorganisms. 2021;9(3):543. Published 2021 Mar 5