First, we have to understand 'skin barrier function'
"The skin barrier is the delicate outer layer or ‘stratum corneum’ of our body and has similar permeability, thickness, and characteristics as a piece of glad wrap," says Prof Goodman. "It is important because it allows us to be terrestrial beings, keeping our insides in and protecting us from the outside environment."
"The skin barrier itself is a delicate balancing organ and starts off life down at the dermo-epidermal junction. The associated skin cells are somewhat communistic in nature; they give up life for the benefit of the body by dying slowly while they come up through the skin layers, becoming devoid of all living matter by the time they reach the surface."
"At this point, they are essentially sheets of interlocked keratin or ‘bricks’, and they stay this way until they are ready to shed. Between those ‘bricks’ are the ‘mortar’ or good oils – we’re talking cholesterol, free fatty acids, ceramides, and sphingomyelins"
(say 'ceramides and sphingomyelins' three times fast)
Goodman continues, "the whole transition from the base to the surface and then falling off the skin as individual cells is highly important as they take with them the allergens and microbes and all of the things you don’t want – a self-replenishing organ, if you like. Each part needs to operate in harmony with the rest to ensure a healthy skin barrier function."
"Another factor to consider is ‘trans-epidermal water loss’ which refers to gradual water loss through the skin tissue. Why is this important? You need 'good bugs' on your skin, and this process maintains a slightly acidic PH and critical level of humidity, fostering a mutually beneficial relationship, where the ‘good’ bugs keep out other nastier pathogens."
What can affect a healthy skin barrier?
"Overzealous cleaning (such as with alkaline soaps), excessive exfoliation (particular physically) and other general lifestyle factors such as changing atmospheric conditions," says Goodman.
So, what about humidity?
Regarding humidity, the best way to see a change in skin barrier function is when someone translocates between climates of a vastly different nature – for example, moving between Darwin (humid) and Perth (dry).
Interestingly, common skin problems can arise from moving either way:
Acne – this can flare up moving from a dry to a humid environment.
Eczema – this can flare up with the opposite transition; humid to dry. This is of particular importance as we transition out of the current humid La Nina weather pattern in Victoria and into dryer Autumn and Winter conditions.
"Essentially, you can be a victim of where you live no matter the climate," says Goodman.
Sigh
To Victoria – our skin is used to living in dryer air. That is, we usually only see a handful of humid days through Summer, as hot desert air blusters in during our normal summer weather patterns. Currently, we’re seeing a lot of tropical weather being dragged down, giving us a summer more akin to Sydney or Brisbane's.
This is, however, not our first and certainly won’t be our last humid summer, so it begs the question – has anything else changed? Well, friends, that may come down to something much more recent in our history. Yes, we are talking about masks.
"Presentations of rosacea, acne and perioral dermatitis (bumps or dryness around the mouth area) have increased. We have also seen a lot of lip dryness – or cheilitis – recently," explains Goodman.
Now, this may seem counter-intuitive given the humidity but it may be that we are altering our skincare routines in an unhelpful way.
We’ve spoken about it before, and we will again – we need to adjust our skincare routine as the seasons change. To keep it simple:
In humid conditions -
Decrease the base – changing the consistency of your base from ointment to cream, cream to serum, strong chemical exfoliant to gentle cleanser, etc. is the most helpful change you can make.
Increase your actives – when our skin is not facing dry air, it is more adept at dealing with stronger active skincare; we’re talking retinols, niacinamides, and the like.
In dry conditions -
Maintain your base – you want to increase the moisture so the atmosphere can’t steal it. This of course depends on your skin type; most people will find moving from a hydrating serum to an ointment will cause their skin to get a little angry.
Reduce your actives – as the dry air strips away the natural moisture of your skin barrier, it is less able to cope with the stress of active skincare. Now don’t let that scare you away from active skincare entirely – they are crucial in maintaining an active and healthy skin barrier, however, in dryer conditions, it is easier to overdo it.