Malassezia: The Yeast of Your Problems

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

Do you ever get itchy, tiny red bumps on your skin or yellow flakes around your scalp? Then you may have fungal issues.

While there are many potential triggers to these conditions, research has shown that the main culprit could be a yeast that lives on your skin: Malassezia.

Our skin is a living ecosystem full of different microbes, including bacteria, mites, viruses, and fungi. Malassezia is the most common genus of fungi found on human skin.

Below is our guide to help you learn about Malassezia, how it can become a problem, and how to manage it.

What is Malassezia?

Malassezia is a type of yeast that is a normal part of the skin’s microbiome (read here to learn what a microbiome is). There are 17 species of Malassezia that mostly live in a mutually beneficial relationship with our skin.

They feed on sebum (the oil our skin produces) to survive, which is why they are commonly found on parts of our body where there is more sebaceous activity, such as our scalp, face, neck, and chest.

In return, Malassezia can help train our immune system, breakdown nutrient compounds for our skin to use, and act as a first line of defense against harmful microbes.

Why can Malassezia be a problem?

When Malassezia feed on our sebum, they leave byproducts (also called metabolites) such as oleic and arachidonic fatty acids. These fatty acids can irritate our skin.

An overabundance of Malassezia and a disrupted skin barrier can cause inflammation, leading to a variety of skin and scalp issues, including:

Dandruff (read more dandruff here)
Seborrheic dermatitis (read more seborrheic dermatitis here)
Malassezia folliculitis (fungal acne)
Psoriasis
Eczema (read more about eczema here)

An overabundance of Malassezia is typically caused by high sebum production. Studies have shown that Malassezia can also thrive in other lipids – particularly lipids composed of fatty acids with carbon chain length of 11-24 (also referred to as long-chain triglycerides, or LCT for short). These are the types of lipids found in most cosmetic ingredients, which include oils, waxes, butters, and esters.

The few oils that Malassezia can not thrive in include medium-chain triglyceride (MCT) oil, squalane (not to be confused with squalene), and mineral oil.

How can we keep Malassezia in check?

Antifungals are an effective method for managing Malassezia. Some of the more common antifungal ingredients include:

Zinc Pyrithione
Ketoconazole
Climbazole
Salicylic acid
Selenium sulfide
Coal Tar

The best antifungal to use depends on the person. Most antifungals can be purchased over-the-counter, but some actives may require a prescription at higher concentrations. If your fungal symptoms are severe, consult a dermatologist to find the best solution for you.

While antifungal treatments can be an effective short-term solution, they might not be effective in the long-run. Many antifungal ingredients are not well tolerated by sensitive skin and scalps and may cause side effects such as:

Rashes/hives
Burning
Itching
Dry/peeling skin

This can cause the scalp to produce more sebum, resulting in increased fungal growth and fungal-related issues if medicated products are not continuously used.

Can natural ingredients help?

Natural ingredients may offer an alternative method for down-regulating Malassezia. The benefit of natural ingredients is that there are often less harsh side effects, although allergic reactions are still a potential side effect which can worsen fungal conditions.

Some ingredients that may help with managing Malassezia include:

Tea tree oil (Melaleuca Alternifolia)
Rosebay extract (Epilobium Angustifolium)
Jua extract (Zizyphus joazeiro bark)
Celery seed extract (Apium graveolens)
Propanediol Caprylate

Conclusion

Malassezia is a yeast that is found on everyone’s skin and scalps. It plays an important role in skin health, but can also be a trigger fungal conditions such as dandruff and fungal acne.

If you have fungal issues, it may be best to avoid products that contain a ton of oils and sensitizing ingredients.

Oils, esters, waxes, and butters are typically composed of fatty acids with carbon chain length 11-24. These oils can mimic our sebum and be used as a food source by Malassezia, allowing the yeast to thrive and multiply.

Sensitizing ingredients, such as fragrances and harsh preservatives, can elicit allergic reactions. Our bodies' immune response can weaken the skin barrier, allowing Malassezia to penetrate deeper into our skin and cause further inflammation.

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 that work for us.

Our products are specially formulated to help you manage Malassezia. Our haircare line is:

Malassezia safe - we exclude fatty acids with carbon chain length of 11-24 that feed the yeast.
Microbiome balancing - we include our proprietary blend of natural ingredients that effectively clean the scalp while balancing the scalp’s microbiome.
Hypoallergenic - we exclude irritating sulfates, fragrances, botanical oils, and dyes that can trigger sensitive skin.
Noncomedogenic - we won’t clog your pores.

Sources

Byrd, A., Belkaid, Y. & Segre, J. [The human skin microbiome](https://www.nature.com/articles/nrmicro.2017.157'#citeas). Nat Rev Microbiol 16, 143–155 (2018). https://doi.org/10.1038/nrmicro.2017.157
Borda LJ, Wikramanayake TC. Seborrheic Dermatitis and Dandruff: A Comprehensive Review. J Clin Investig Dermatol. 2015 Dec;3(2):10.13188/2373-1044.1000019. doi: 10.13188/2373-1044.1000019. Epub 2015 Dec 15. PMID: 27148560; PMCID: PMC4852869.
Narshana, M., and P. Ravikumar. An overview of dandruff and novel formulations as a treatment strategy. Int J Pharm Sci Res 9.2 (2018): 417-431.
Saunte DML, Gaitanis G, Hay RJ. *Malassezia-*Associated Skin Diseases, the Use of Diagnostics and Treatment. Front Cell Infect Microbiol. 2020 Mar 20;10:112. doi: 10.3389/fcimb.2020.00112. PMID: 32266163; PMCID: PMC7098993.
Wilde PF, Stewart PS. A study of the fatty acid metabolism of the yeast Pityrosporum ovale. Biochem J. 1968 Jun;108(2):225-31. doi: 10.1042/bj1080225. PMID: 5691082; PMCID: PMC1198797.