How Stress and Hormones Disrupt the Skin Microbiome - and How Prebiotics Can Help

By The SABI

We often think of stress and hormones as internal issues: headaches, fatigue, mood swings. But one of the first places they leave a fingerprint is on the skin. Breakouts that appear after a deadline, flare-ups around your period, dryness after months of high stress: it’s not random. It’s the skin microbiome, the living ecosystem of microbes on your skin, reacting to internal changes.

And here’s the geeky bit: scientists now know that this microbial balance is influenced directly by cortisol, oestrogen, and androgens. Stress and hormonal flux alter the very terrain that skin bacteria live in. The result? Less microbial diversity, a weaker barrier, and more space for “troublemaker” microbes to thrive.

The solution isn’t to strip skin harder. It’s to feed and strengthen the ecosystem itself. 

Stress and the Microbiome: Cortisol’s Cascade

When stress hits, cortisol levels rise. Cortisol is catabolic - it breaks things down, including skin barrier lipids. Research shows elevated cortisol leads to:

• Thinner barrier function → transepidermal water loss (TEWL) increases, skin dries out.
  

• pH shifts → making skin less acidic, favouring pathogenic microbes like Staphylococcus aureus.
  

• Lower microbial diversity → chronic stress reduces populations of commensal bacteria that normally suppress inflammation (Chen et al., 2018).
  

That’s why after long periods of stress, skin doesn’t just look “tired”, it becomes biologically less resilient.

Hormonal Swings: Oestrogen, Progesterone, Androgens

Skin is a hormone-sensitive organ. The sebaceous glands, keratinocytes, and even skin microbes respond to circulating hormones:

• Oestrogen: promotes collagen synthesis, ceramide production, and a strong barrier. When levels drop (postpartum, perimenopause), skin thins, dries, and becomes more sensitive (Thornton, 2013).
  

• Progesterone: can increase vascular permeability, leading to puffiness and inflammation.
  

• Androgens (e.g., testosterone): increase sebum production, fuelling acne-linked bacteria like Cutibacterium acnes.
  

These shifts change the “nutrient landscape” of the skin, and the microbiome shifts with them. Too much oil and clogged pores → acne overgrowth. Too little oil and reduced ceramides → dry, reactive skin more prone to eczema flares.

The Microbiome in Distress: What We See on the Surface

When stress hormones or sex hormones destabilise the skin ecosystem, three big patterns appear:

1. Acne flares → driven by excess sebum and proliferation of C. acnes.
   

2. Eczema/dermatitis → linked with reduced microbial diversity and S. aureus dominance (Kong et al., 2012).
   

3. Barrier breakdown → dehydration, redness, sensitivity, accelerated visible ageing.
   

It’s a microbial imbalance first, then a visible skin issue second.

Why Prebiotics Work (and Probiotics Often Don’t)

Probiotic skincare gets hype, but here’s the problem: live bacteria rarely survive the shelf life of a cream. By the time you open the jar, they’re often dead (Lew et al., 2020).

Prebiotics are different. They are plant-derived fibres and oligosaccharides that act as selective food for good microbes already living on your skin. Clinical studies show that topical prebiotics:

• Increase commensal bacteria like S. epidermidis.
  

• Decrease pathogens like S. aureus.
  

• Improve skin hydration and reduce sensitivity within weeks (Guéniche et al., 2010).
  

Think of probiotics as “adding tenants” to a building — they may or may not stick. Prebiotics are like feeding the best tenants you already have, making them stronger and more resilient.

The Prebiotic Moisturiser: Stress-Smart Skincare

This is exactly why we formulated The Prebiotic Moisturiser.

It goes beyond hydration by combining:

• Prebiotics to feed protective bacteria and rebalance the microbiome.
  

• Hyaluronic acid to restore hydration lost through cortisol-induced TEWL.
  

• Collagen-supporting botanicals to counteract oestrogen dips and strengthen barrier resilience.
  

The result? Skin that can ride out stress spikes and hormonal swings with fewer flare-ups and more glow.

Stress and Hormones Are Inevitable, Imbalance Doesn’t Have to Be

We can’t eliminate stress or stop hormonal shifts. But we can support the ecosystems they disrupt. By feeding beneficial microbes, protecting barrier integrity, and giving skin the tools to defend itself, prebiotic skincare flips the script from “damage control” to “ecosystem care.”

So the next time stress or hormones send your skin sideways, don’t reach for something harsh. Reach for something that feeds your microbes, because when your microbiome thrives, your skin does too.

HORMONAL & PROUD

Created as a brand to help women navigate the toughest moments in pregnancy, childbirth, postpartum — and practically every stage of life –– The SABI is changing the narrative around our hormones from one of taboo, embarrassment, and loneliness to awareness and even, pride. As more than a wellness brand, The SABI offers a carefully-crafted line of products to carry you through your hormonal journey, including rituals, supportive tools, and ancient herbal remedies that have been tested time and time again by women and now come backed by medicine. The SABI is a blend of science and nature conceived by women who have experienced the joys and deep struggles of bringing a child into the world, the pains of a heavy, difficult period, miscarriage, and difficulty conceiving.

We invite you to get to know your body and its cycles better –– to really understand what is going on inside. Learn to use your hormones to your advantage no matter your stage of life, and know that you can support and balance your hormone levels. We are here to help with the information, understanding and natural tools to support your body and the emotional process along with it.

DISCLAIMER

The SABI blog and articles are not meant to instruct or advise on medical or health conditions, but to inform. The information and opinions presented here do not substitute professional medical advice or consultations with healthcare professionals for your unique situation

References

• Chen YE, Fischbach MA, Belkaid Y. Skin microbiota–host interactions. Nature. 2018.
  
  

• Thornton MJ. Oestrogen functions in skin health. Br J Dermatol. 2013.
  
  

• Kong HH, et al. Altered skin microbiome in atopic dermatitis. Genome Res. 2012.
  
  

• Lew LC, et al. Challenges in probiotic skincare. Front Microbiol. 2020.
  
  

• Guéniche A, et al. Prebiotics and the skin microbiome. J Dermatol Sci. 2010.