Acne and quorum sensing: what happens when the bacteria in your skin talk too much
22/06/2026Acne and quorum sensing: what happens when the bacteria in your skin talk too much
22/06/2026
Heat, sweat and sunshine can negatively affect greasy skin and encourage spots and pimples. Learn how to take a scientific, gentle approach to looking after acne-prone skin during the summer.
Why can acne get worse during the summer?
In the summer, the skin’s environment changes: temperatures increase, we sweat more, we spend more time outdoors and we use sunscreen more frequently. All of this can affect how greasy skin or acne-prone skin behaves.
So it’s not unusual for your skin to look shinier, its pores to get more clogged, or spots and pimples to appear. Heat alone does not “cause” acne, but it can contribute to creating an environment that upsets the skin’s balance more easily.
Does sunshine really improve spots, or just conceal them?
Science increasingly draws attention to the role external factors play in acne. Solar radiation, temperature, humidity, pollution, stress, diet, some cosmetics and particular skincare routines can affect its onset, duration or severity. These factors can interact with the skin barrier, sebaceous glands, immune response and skin microbiota.
Skin microbiota play a key role in acne-prone skin: when their balance gets upset, processes relating to excess sebum, inflammation and the appearance of blemishes can be amplified, as we explain in our article on why skin microbiota can affect acne.
But there is a factor that often creates confusion in the summer: the sun. Lots of people feel as if it “dries out” their spots, or that their skin looks better for a few days. And this may seem to be true: a suntan can conceal redness and blemishes, and skin can initially look less greasy.
However, this improvement may only be temporary.
Solar radiation can initially cause improvement in some lesions, but it also encourages flare-ups, pro-inflammatory responses, reddening and blemishes, i.e. visible blemishes that remain after the spots have improved.
So in summer, be wary of thinking that the sun will “cure” spots. Acne-prone skin needs a routine adjusted to the heat: sunscreen, gentle cleansing to remove sweat and lightweight products that help keep it in balance.
Heat, sweat and oils: the triangle that can encourage spots
In acne-prone skin, excess oils can create an environment more conducive to pores becoming clogged and spots and pimples appearing. In addition, when the skin’s microbiota balance is altered, bacteria such as Cutibacterium acnes —that are a normal part of the skin and beneficial for it— can proliferate more than usual. This imbalance is called dysbiosis.
When it happens, Cutibacterium acnes can use a communications system called quorum sensing: bacteria send signals to each other and, when they detect that there are enough of them present, can coordinate as a team and trigger activities that end up causing the spots and other blemishes typical of acne. This is why, with acne-prone skin, it’s not just what we can see on the surface that matters; what’s happening to the skin’s invisible balance does too.
In the summer, this environment can intensify. When sweat, oils and traces of sunscreen remain on the skin for a long time, its pores can feel more clogged and this encourages the appearance of spots.
This process can be exacerbated when sweat and oils mix with:
- Traces of sunscreen, or makeup.
- Pollution.
- Dead skin cells.
- Products that are too "heavy" or greasy.
Scientific evidence shows that acne is linked to processes such as excess sebum, clogged pores, inflammation and changes in the skin’s microbiota. In addition, external factors such as heat, humidity, solar radiation and some cosmetics can affect how acne-prone skin reacts.
So in the summer, it is crucial not to remove all oils or use aggressive skin cleansing products. What you need to do is keep the skin’s balance intact; wash sweat off thoroughly, choose sunscreens suitable for greasy skins, avoid using “heavy” products, choose light textures and follow a simple care routine for greasy, acne-prone skin.
Spots on the back and chest
Summer acne doesn’t always appear only on the face. Spots can also appear on the back, chest or shoulders, especially when heat, sweat, tight clothing and fabrics that don’t let the skin breathe properly come together.
This can happen, for example, after doing sport, or wearing a rucksack, body-hugging outfits or sweat-damp clothes for a long time. These create the conditions for exposing the skin to a less-than-ideal blend: damp, rubbing and occlusion.
In dermatology, these types of lesion are linked to what is called mechanical acne, that can appear or worsen due to rubbing, pressure, heat, sweat or repeated occlusion of the skin. Factors such as tight-fitting clothes, sports gear or accessories that constantly rub can encourage these kinds of spots, and excessive sweating and overheating can exacerbate the severity of lesions.
- To mitigate this environment, some simple tricks can help:
- Change your clothes after training or sweating a lot.
- Take a shower after exercise or going to the beach.
- Choose clothing that lets your skin breathe.
- Don’t wear damp clothes for extended periods.
Facial cleansing in the summer
How many times should you wash your face?
If your skin gets greasy in the summer, it might seem logical to wash your face each time it becomes shiny. But washing it too many times a day does not always help to reduce spots or pimples on your face. In fact, excessive cleansing can cause skin irritation and negatively affect its natural barrier.
As a general rule, use a cleansing product specifically for acne-prone skin twice daily. Morning and night is usually enough.
The literature on cleansing and acne underlines that many people believe acne has to do with a lack of hygiene, and this is why they cleanse aggressively or too often. However, proper cleansing can help to remove impurities without damaging the skin barrier.
Mistakes that can make spots worse
In the summer, there are some common mistakes that can worsen the sensation of greasy skin, cause irritation, or encourage more spots and pimples to appear.
- Over-cleansing your skin: washing your skin too many times or using very aggressive cleansing products can have a negative effect on the skin barrier.
- Using products that are too drying: the feeling of skin tightness does not mean that the skin is cleaner; it is often a sign of irritation.
- Excessive exfoliation: using acidic products, scrubs or exfoliative products can increase the skin’s sensitivity and make inflammation worse.
- Not washing sunscreen off properly: at the end of the day, and particularly if you have been reapplying sunscreen frequently, you should cleanse your skin thoroughly to remove traces of it, along with sweat, sebum and pollution.
Recent reviews on acne and the skin barrier highlight the importance of optimising daily care in order to reduce irritation, improve the barrier function and encourage long-term adherence.
Looking after acne-prone skin isn’t about bombarding it, but about understanding what it needs: a way of looking after acne-prone skin without damaging it, even in the summer when heat, sweat and changes to routine can put its balance to the test.
The key is to turn these habits —protecting, gently cleansing and respecting the skin’s balance— into a simple, permanent routine.
Vincobiosis® Acneic: the gentle routine for acne-prone skin
Now we’ve talked about heat, sweat, sunscreen and cleansing, the question is: how to accommodate all this in a simple routine?
Vincobiosis® Acneic offers a comprehensive routine in 3 steps for acne-prone skin. What sets it apart is Canonia Allysis®, a unique, plant-based biotechnological ingredient that takes its inspiration from the defence system used by some plants.
These plants are able to keep bacteria under control without harming them: they produce molecules that block their communication and prevent them from acting together to cause harmful effects. Canonia Allysis® uses this mechanism as the basis for helping to reduce blemishes on acne-prone skin working from the inside out, blocking communication between out-of-control bacteria and restoring natural balance to the skin’s microbiota.
A smart, innovative and gentle way to look after acne-prone skin: not by attacking its ecosystem, but by helping it to recover its balance.
Step 1: Cleansing mousse
Dermo-balancing cleansing mousse cleanses deeply, helping to reduce impurities and regulate excess sebum, and respecting the skin’s microbiota balance. Apply morning and night to damp skin, massage in gently and rinse off with water.
Step 2: Facial gel cream
Dermo-balancing facial gel cream provides daily skincare for the face. It helps to reduce spots, pimples, blemishes, redness and excess sebum, keeping the skin moisturised, soft and comfortable. Apply to clean, dry skin once or twice per day.
H3. Step 3: Body lotion spray
Body lotion spray rounds off the body skincare routine, particularly on the back and chest. Apply to dry skin, spraying on from no more than 5 cm distance, and allow to absorb before putting clothes on.
You can find Vincobiosis® Acneic products in your local pharmacy.
Or if you prefer, you can also buy them online via approved sales outlets. View sales outlets and buy online View sales outlets and buy online.
Literature references:
- Sardana, K., Sharma, R. C., & Sarkar, R. (2002). Seasonal variation in acne vulgaris—Myth or reality. The Journal of Dermatology, 29(8), 484–488. https://doi.org/10.1111/j.1346-8138.2002.tb00313.x
- Dréno, B., Bettoli, V., Araviiskaia, E., Sanchez Viera, M., & Bouloc, A. (2018). The influence of exposome on acne. Journal of the European Academy of Dermatology and Venereology, 32(5), 812–819. https://doi.org/10.1111/jdv.14820
- Piquero-Casals, J., Morgado-Carrasco, D., Rozas-Muñoz, E., Mir-Bonafé, J. F., Trullàs, C., Jourdan, E., Piquero-Martin, J., Zouboulis, C. C., & Krutmann, J. (2023). Sun exposure, a relevant exposome factor in acne patients and how photoprotection can improve outcomes. Journal of Cosmetic Dermatology, 22(6), 1919–1928. https://doi.org/10.1111/jocd.15726
- Gorajek, A., Kudan, M., Osiejewska, A., Grądzik, A., Mikut, K., Wojtachnio, D., Nowakowska, I., & Bartoszewicz, J. (2022). Mechanical acne: A review of contributing factors and diagnostic-therapeutic approach. Journal of Education, Health and Sport, 12(8), 473–483. https://doi.org/10.12775/JEHS.2022.12.08.049
- Starzyk, T., Aust, N., Schur, N., & Miller, R. (2025). Comedogenicity in cosmeceuticals: A review of clinical relevance, regulatory gaps, and future directions. JAAD Reviews, 6, 78–83. https://doi.org/10.1016/j.jdrv.2025.09.002
- Puaratanaarunkon, T., & Asawanonda, P. (2022). A randomized, double blinded, split-face study of the efficacy of using a broad spectrum sunscreen with anti-inflammatory agent to reduce post inflammatory hyperpigmentation after picosecond laser. Clinical, Cosmetic and Investigational Dermatology, 15, 331–337. https://doi.org/10.2147/CCID.S355329
- National Institute for Health and Care Excellence. (2021). Acne vulgaris: Management (NICE guideline NG198). NICE. https://www.nice.org.uk/guidance/ng198
- Levin, J. (2016). The relationship of proper skin cleansing to pathophysiology, clinical benefits, and the concomitant use of prescription topical therapies in patients with acne vulgaris. Dermatologic Clinics, 34(2), 133–145. https://doi.org/10.1016/j.det.2015.11.001
- Schachner, L. A., Alexis, A. F., Andriessen, A., Berson, D., Gold, M., Goldberg, D. J., Hu, S., Keri, J., Kircik, L., & Woolery-Lloyd, H. (2023). Insights into acne and the skin barrier: Optimizing treatment regimens with ceramide-containing skincare. Journal of Cosmetic Dermatology, 22(11), 2902–2909. https://doi.org/10.1111/jocd.15946
- Taylor, S., Elbuluk, N., Grimes, P., & al. (2023). Treatment recommendations for acne-associated hyperpigmentation: Results of the Delphi consensus process and a literature review. Journal of the American Academy of Dermatology, 89(2), 316–323. https://doi.org/10.1016/j.jaad.2023.02.042
