At the time of writing, we are still on our family summer holiday. With teenagers with acne-prone skin, this has led to problems with skin sensitivity to the sun due to concurrent retinoid use, mild sunburn 🥵(they no longer let me apply sunscreen on them or listen to my prompts to reapply 🙄 – I am a strong advocate of letting learning happen from failure!), and also dryness from repeated swimming in the sea or in the pool 🏊.
Acne is a skin problem that is well recognised to be associated with increased levels of grease (or sebum) on the skin. So it is odd that acne-sufferers still suffer from acne after a drying activity such as swimming especially in antimicrobial chlorinated water. There have been suggestions that there is a compensatory ‘rebound’ increase in sebum production after long-term water immersion.
Interestingly, there is a paper on this topic in the May/June edition of the journal Pediatric Dermatology.
[Morss-Walton PC, Kimball R, Rosales Santillan M et al. Effects of swimming on facial sebum in adolescents. Pediatr Dermatol 2022;39:376-378.]
What did they look at?
The authors looked at 16 swim team members aged 12-18y who swam 6 days a week (I know, it’s a small study!). Their acne was evaluated at baseline by 2 dermatologists using the Leeds Acne Severity Scale that we commonly use to score acne. Photos (regular and fluorescent) were taken before and after 1 hour of swimming in a chlorine-treated pool and sebum levels were measured via the presence of a fluorescing sebum derivative. Shine was also looked at, but via a photographic measurement of captured light reflection.
What did they find?
7 of the 16 swimmers had acne. They do not go on to elaborate on acne severity. Not surprisingly, those with acne had higher baseline levels of sebum than those without acne and they also had higher levels of baseline shine.
The swimmers without acne showed a significant decrease in sebum and shine measurements after swimming whereas those with acne did not experience a statistically significant decrease in their sebum levels or shine levels after swimming.
Why did this happen?
The authors postulate that follicular sebum, rather than superficial sebum may be more important in the development of acne. They suggest that shine is a marker of superficial sebum and that shine levels in those with acne decreased by 59% (apparently this was not statistically significant) but that follicular sebum only fell by 19%.
Hence, the reduction in superficial sebum gives the sensation of dryness but because the follicular sebum is less affected, the acne is ongoing.
What are the implications?
It’s tricky then. A lot of the facewashes and topical products advised in the management of acne involve drying and irritating products such as salicylic acid, lactic acid, benzoyl peroxide or retinoids.
In our case, we held off the retinoids for a few days, substituted the salicylic acid facewash with a gentle oil free facewash, increased the use oil free moisturisers, increased the frequency of application of oil free facial sunscreens through the day and things settled eventually.
Dr Sandy Flann, Consultant Dermatologist.