Why Scalp Health is Skin Health

You already know the drill regarding facial skin care—cleansers, moisturizers, SPFs, just to name the basics—but how many of you care for your scalp beyond washing it?

The scalp is often overlooked in skin care discussions despite enduring similar external and internal stressors as the rest of your skin. These stressors hasten aging, inflammation, and structural decline. As the scalp skin is the biological anchor for hair follicles, this aging can negatively affect its health, decreasing hair quality, density, and strength.

So, what are some of these sources of damage to your scalp, and how can you care for your scalp like you care for the rest of your skin?

How Is The Skin On Your Scalp Unique?

The skin on your scalp is fairly unique due to the high sebum production and concentration of hair follicles. Driven by a dense concentration of hair follicles and sweat glands, the scalp's elevated sebum levels provide an ideal bacterial and fungal growth environment if not properly managed. A disrupted scalp microbiome can leave your scalp predisposed to dandruff, seborrheic dermatitis, tinea capitis, pediculosis capitis, and psoriasis.[1]

Moreover, the scalp’s higher density of hair follicles means it has a greater metabolic demand and blood flow. One of the primary effects of aging on the scalp is a decrease in microvasculature or blood vessels through the skin. Age-related nutrient deficiencies, impaired microcirculation, or hormonal imbalances can significantly impact the scalp's function and cause a thinning of the scalp and, potentially, hair loss.[2]

What Are Some Common Causes of Scalp Health Disruptors?

Many things can throw your scalp out of balance, causing irritation, inflammation, and even stunting your hair growth. From natural aging processes like cellular senescence to lifestyle habits, here are some of the factors that can make a big difference to the health of your scalp:

Oxidative Stress

Your scalp is constantly exposed to oxidative stress from internal and external sources, such as UV radiation and pollution. Over time, reactive oxygen species (ROS) or free radicals create damage that accelerates cellular deterioration, impairs the scalp’s repair mechanisms, and contributes to premature follicular aging, which in turn causes increased inflammation.[3]

So what does this oxidative stress mean for your hair? As you age, your natural antioxidant defenses decline, further amplifying the effects of oxidative stress. Emerging evidence suggests that oxidative stress directly affects your hair follicles and is a central factor in hair graying and alopecia.[4]

Cellular Senescence

Like the skin on the rest of your body, your scalp accumulates senescent cells throughout your life. These senescent cells become dysfunctional and release inflammatory factors known as senescence-associated secretory phenotype (SASP) that can send surrounding cells into premature senescence. Within your hair follicles, senescence affects the cells responsible for hair growth, like dermal papilla cells (DPCs) and outer root sheath cells (ORSCs), contributing to thinning and hair loss.[5,6]

What's more, stress and oxidative damage only make things worse. Hormones like corticotropin-releasing hormone (CRH), which spikes during stressful periods (and even pregnancy), have been shown to push hair follicle cells into premature senescence, disrupting growth cycles.[7] Luckily, a decrease in senescent ORSCs has been associated with hair re-growth, meaning that some age-related hair loss may be reversible.[8]

Lifestyle Habits

Your daily habits—what you eat, how well you manage stress, and even how you sleep—can profoundly impact your scalp health. Here are how some common lifestyle choices can affect the health of your scalp and the appearance of your hair:

• Sleep: Sleep is when the body repairs and regenerates cells, including those in the scalp. Research has indicated that people with sleep disorders have a higher risk of developing certain forms of alopecia, likely due to increased inflammatory markers that interfere with regular follicular activity.[9]
• Diet: Hair follicles need a steady supply of nutrients, proteins, and vitamins to produce hair. A diet lacking these nutrients can impair scalp health and follicular function, leading to slower hair growth and increased fragility. Plus, if you aren't getting enough antioxidants from your diet, your scalp may be more vulnerable to oxidative stress that can contribute to premature scalp aging.[10]
• Stress: Chronic stress can seriously disrupt the health of your scalp and hair follicles. High levels of stress increase cortisol, which can push hair follicles into a resting (telogen) phase too soon, potentially leading to increased shedding and slower regrowth.[11] Prolonged exposure to stress hormones may also trigger inflammation, worsening scalp conditions like dandruff or psoriasis.[12]
• Hair Care: Overwashing with harsh shampoos can strip the scalp of its natural oils, leading to irritation and barrier dysfunction. These products can also disrupt the delicate scalp microbiome, weakening the skin barrier and causing dandruff or irritation. Too much heat styling can also weaken hair and contribute to follicle damage.
• Alcohol: The link between alcohol and hair health is complex—some studies suggest that moderate drinking might reduce the risk of certain types of hair loss, but too much alcohol can trigger inflammation and nutrient deficiencies that negatively impact scalp health, leading to premature scalp aging.[9]
• Obesity: Obesity has been linked to systemic inflammation, which can contribute to scalp-related issues and hair loss. Higher levels of oxidative stress and hormonal imbalances associated with excess weight may contribute to follicular miniaturization and an increased risk of certain types of hair loss.[9]

How to Support Scalp Health for Optimal Hair Growth

A healthy scalp is the foundation for strong, vibrant hair. If you’re dealing with thinning hair, dandruff, or irritation, it might be time to take a closer look at how you’re supporting your scalp:

Nutrient delivery

Your scalp needs the proper nutrients to grow strong and healthy hair. Here are some common sources of nutrients that may help reinforce your scalp health:

• Iron: Iron deficiency is one of the most common nutritional deficiencies and can contribute to hair thinning—although the degree to which it is responsible is still unclear. A diet rich in iron may help counteract these effects (and some of the others associated with anemia)[10]
• Zinc: Zinc, a key trace mineral, plays a role in gene expression and cell function. When your body lacks zinc, it can lead to hair brittleness and a host of other side effects. Support your hair growth with zinc rich foods like meats, whole grains, and nuts.[10]
• Fatty acids: Fatty acids like omega-3 and omega-6 help your body naturally modulate androgen activity and inhibit 5α-reductase, a mechanism similar to the action of finasteride. While the effects will not be as drastic, ensuring your diet contains plenty of healthy fatty acids can keep your scalp and hair healthy.[10]
• Biotin: While biotin is frequently marketed for hair growth, clinical trials have not demonstrated its efficacy in individuals without a deficiency.[10]

Microbiome balance

The scalp microbiome is pivotal in maintaining skin homeostasis and preventing inflammatory conditions like dandruff and seborrheic dermatitis. Many traditional treatments for these conditions rely on shampoos containing zinc pyrithione, ketoconazole, selenium sulfide, and salicylic acid, which target fungal and microbial imbalances.[14]

However, these treatments can sometimes cause irritation or dryness. Emerging research suggests a more holistic approach involving microbiome-friendly scalp treatments like pre and postbiotics. This may provide a gentler alternative to targeting these scalp concerns by maintaining microbial diversity.[14]

Antioxidants

Antioxidants in your diet and topical products can help reinforce your scalp against oxidative stress. However, research indicates that while dietary antioxidants support endogenous antioxidant systems, excessive supplementation with isolated antioxidants may paradoxically increase oxidative stress. Whole-food sources of antioxidants, such as berries, nuts, and leafy greens, are generally safer and more effective.[10]

When searching for topical products containing antioxidants, look for those validated to support the health of your hair and scalp, like vitamin E, A, and D.[10]

Key Takeaways

• Treating your scalp like the rest of your skin helps prevent inflammation and hair thinning.
• Oxidative stress weakens hair follicles, leading to thinning and graying. Your body's antioxidant defenses decline with age, making scalp protection vital.
• Stress and oxidative damage accelerate cellular aging, sending cells into premature senescence, triggering inflammation and follicle damage.
• Poor sleep, diet, and stress can influence hair growth and scalp conditions.

References

1. https://pubmed.ncbi.nlm.nih.gov/16382661/
2. https://www.ncbi.nlm.nih.gov/books/NBK551565/
3. https://pmc.ncbi.nlm.nih.gov/articles/PMC11196958/
4. https://pmc.ncbi.nlm.nih.gov/articles/PMC2929555/
5. https://pubmed.ncbi.nlm.nih.gov/39614601/
6. https://www.sciencedirect.com/science/article/abs/pii/S0923181117300269
7. https://pmc.ncbi.nlm.nih.gov/articles/PMC11068553/
8. https://pmc.ncbi.nlm.nih.gov/articles/PMC8929036/
9. https://pmc.ncbi.nlm.nih.gov/articles/PMC8835065/
10. https://pmc.ncbi.nlm.nih.gov/articles/PMC5315033/
11. https://www.ncbi.nlm.nih.gov/books/NBK430848/
12. https://pmc.ncbi.nlm.nih.gov/articles/PMC8519049/
13. https://pmc.ncbi.nlm.nih.gov/articles/PMC8138261/
14. https://pmc.ncbi.nlm.nih.gov/articles/PMC11064082/