To understand why your scalp is the way it is and how to care for it better, we have to zoom in and take matters into our hands at a microscopic level. Living invisibly on our scalps are entire ecosystems of bacteria, fungi, and other microbes interacting with our cells in ways that profoundly impact the health and beauty of our hair.
An out-of-balance microbiome might be the culprit behind a lot of your irritating scalp and hair conditions and by cultivating the right microbial communities, we can troubleshoot issues right at the root. Hopefully, this in-depth article on scalp microbiome will help you understand the root of your hair (and problems in turn, huh) aka your scalp, and care for it better.
What Is the Scalp Microbiome?
The scalp microbiome refers to the ecosystem of bacteria, fungi, viruses, and other microorganisms that inhabit the scalp skin and hair follicles. Like in the gut, these microscopic bugs interact with cells and nerves in the scalp to influence health in various ways.
Common bacteria found in your scalp microbiome
The most abundant bacteria identified on healthy scalps are Staphylococcus, Cutibacterium, Micrococcus, and Malassezia. These common scalp residents act as “gatekeepers” that help prevent colonization by more harmful microbes.
How does the scalp microbiome develop?
We first acquire scalp microbes during the birthing process, then the diversity expands rapidly over the first years of life. Genetics, age, hormones, lifestyle habits, and hair care practices all help shape each individual’s unique scalp microbiome signature. This signature tends to stabilize by adulthood but still fluctuates over time.
Signs that Suggest an Imbalance in Your Scalp Microbiome
Your Dandruff Is Getting out Of Control
One of the most common scalp disorders is dandruff, characterized by itchy, flaky skin shedding. Dandruff arises when lipids and enzymes from fungi of the genus Malassezia irritate and inflame the scalp. Under healthy conditions, Malassezia is kept in check by the resident bacteria. However environmental factors can allow the overgrowth of these fungi, disrupting balance and triggering inflammation and cell turnover that presents as dandruff flakes.
Worsening hair loss
For those genetically prone to balding and hair thinning, unwanted microbes may exacerbate hair loss. Bacteria like Staphylococcus aureus produce enzymes that can trigger alopecia and degrade follicle cell structures. This microbial assault on the follicles can hasten miniaturization and hair falling out over time. Keeping your scalp microbiome balance in check may help slow the progression of genetic hair loss.
Developing Problematic Scalp Conditions
An imbalance in the scalp microbiome underlies several other frequently encountered scalp conditions like folliculitis (inflammation with infected hair follicles), seborrheic dermatitis with red, oily skin patches, psoriasis with thick scaly areas, and secondary infections of existing wounds or lesions.
The Scalp Microbiome Shields Your Scalp From Harm
Fending off pathogens
By crowding out real estate on the scalp and producing antimicrobial chemicals, resident microbes create resistance against invasion by disease-causing microorganisms like Staph bacteria or ringworm fungi. When this protective shield gets disrupted, pathogens can sneak in and trigger issues like infections, itchiness, and inflammation.
The immune sensors in scalp skin cells constantly monitor microbe activity and sound the alarm at the first sign of threatening bugs. This triggers the release of inflammatory signals which must be controlled to prevent harmful inflammation. Friendly scalp microbes help turn the volume down on these signals, while harmful bugs crank up the volume.
Your Scalp Microbes Directly Influence Hair Growth Cycles
Signaling hair follicle stem cells
The hair growth cycle is controlled by specialized stem cells that sit in the follicle base. As these master cells transition between active and resting phases, they cyclically produce new hair shafts. Fascinating research shows that scalp microbes may help coordinate stem cell activity through chemical signaling, acting as microbial managers of hair follicle growth cycles.
Interacting with hormones
Hormones like estrogen and testosterone also tune the hair growth tempo by binding receptors in the follicles. Certain scalp microbes can alter hormonal messages to the stem cells by degrading hormones or modulating receptor activity. For example, some bacteria possess enzymes that break down testosterone, while others reduce the sensitivity of follicle cells to androgen hormones. This microbe-hormone interplay may impact the rate of hair growth or thinning over time.
Tips for Maintaining a Healthy Scalp Microbiome
Reduce the use of antibacterial products
Many conventional shampoos and hair products contain harsh detergents and biocides that can severely deplete beneficial bugs in the scalp microbiome.
For every cycle of climbazole shampoo you apply to your flaky scalp, you destabilize the natural bacterial culture of your scalp for the worse.
Limit the use of antibacterial ingredients to prevent disruption of microbial balance and opt for natural oils instead. In fact, study shows that uncultured Malassezia, which is more abundant in dandruff scalp (25.26%) compared to healthy scalp (14.44%), decreases by 6.89% in dandruff scalp after applying coconut oil.
Personally, when I feel my scalp getting irritated, I mix a few drops of tea tree essential oil into coconut oil as a gentle, antimicrobial alternative to harsh commercial shampoos. Gotta give props to my crafty grandma for this mixture.
Stimulate Growth of Beneficial Microbes
Just like in our guts, providing the right nutrition for helpful scalp microbes supports their growth and activity. Occasionally massaging oils like argan, coconut or olive into my scalp leaves those tiny workers happy, keeping my natural defense barrier intact. A healthy scalp microbiome means no flakes or itches for this girl!
Try Probiotic Scalp Treatments
Some emerging probiotic scalp treatments contain non-pathogenic bacteria scientifically demonstrated to improve scalp health. These live microbes may crowd out harmful bugs when applied topically. Early clinical results applying probiotic strains like Lactobacillus paracasei have shown a significant reduction in dandruff, itching, and inflammation in studies.
Get Adequate Sun Exposure
Emerging research reveals that exposure to sunlight promotes the growth of beneficial microbes across body sites like the gut and skin. Sunlight triggers vitamin D production in the skin, and vitamin D then stimulates the release of antimicrobial peptides – small proteins that alter the microbiome. By avoiding the sun you’re depriving your scalp of vitamin D, allowing unfavorable growth of otherwise healthy microbes like Propionibacterium which can trigger scalp acne.
Analyze Your Scalp Microbiome
Good news for the nerds who are curious about the bacterial composition of their scalps- at-home scalp microbiome test kits now allow mapping your unique scalp microbiome signature. Sending in a small hair sample for DNA analysis shows which bacteria dominate, highlighting imbalanced communities and allowing dysfunctional microbes to thrive. This knowledge opens doors for targeted modulation of unhealthy scalp microbiomes.
The diverse microbial ecosystem residing on our scalps profoundly impacts the health and beauty of our hair by fending off pathogens, calming inflammation, and directing the complex hair growth cycle. By avoiding excessive antimicrobial products and nurturing our scalp microbiome with microbiome-friendly habits, we can help cultivate strong, shiny hair from root to tip!