For most people, seasonal skincare is a product swap – lighter lotions in summer, heavier creams in winter. By that logic, your skin shouldn’t need to change its moisture levels from season to season, because you’re just changing its products. But the products aren’t the thing. It’s the net moisturization that they provide. And what breaks down during seasonal shifts isn’t your moisture level. It’s your barrier.
What Seasonal Air Actually Does To Your Skin
The normal function of cells in the stratum corneum depends mainly on its hydration (Chessa et al., 2020). Cold air does not contain much moisture. When it is heated for indoor comfort, its relative humidity drops significantly. As the American Academy of Dermatology states, indoor relative humidity levels drop to about 10% to 20%. Our skin tries to compensate for the lack of ambient humidity by increasing its water content through transepidermal water loss. TEWL is the amount of water that passes through the skin from inside the body to the outside environment. This evacuation of insufficiently protected intercellular water shows up as dry, flaky skin.
However, with a decline in humidity and a reduction in the skin’s ability to produce natural moisturizing factors and lipids, which occurs with age, the skin’s barrier function becomes progressively worse. Skin cells shrivel up and die as the intercellular matrix loses too much water. Skin feels dry, tight, and itchy as a result of thinning and tightening of the skin and surrounding regions.
Building The Occlusive Layer Your Skin Is Missing
An occlusive is a substance that physically blocks the skin surface and prevents water loss. Petroleum jelly is a typical occlusive. Oils act as occlusives in a different way, depending on their fatty acid profile – and whether they stay on the skin and protect, or absorb and nourish.
The “slugging” practice – where you apply a rich oil or balm as your final step at night – makes sense as the oil works as a repair occlusive overnight when the skin is at its peak of natural regeneration. Also, when you’re in the swings-state weather of “warmish day/freezing night” this little extra can help stabilise a barrier that feels under siege from endlessly re-equilibrating.
An oil’s fatty acid profile is determined by the type of plant it comes from and the method used to extract it. A cold-pressed, chemical-free extraction will be the one least compromised in terms of fatty acid content. Products like organic hexane free castor oil is high in ricinoleic acid and has powerful anti-inflammatory, and also, in this case, occlusive properties – but make sure you stick to the solvent rules about what’s counter-productive.
Non-comedogenic is the phrase you’re looking for on any oil you’re considering using on your face – occlusion is no good if it’s also clogging up the works.
Protecting The Scalp Through Seasonal Stress
The scalp microbiome is often forgotten here. As humidity levels fall and we crank up the radiator, the scalp goes into what appears to be either overproduction or underproduction of sebum. In reality, it’s the delicate microbial balance being disrupted, and you may see flaking, itching, or unexpected oiliness.
Hair really doesn’t hydrate as skin does – it’s physically impossible. But the keratin matrix of each strand does swell and shrink in response to water, and when it swings far to the dry side, the cuticle gets rough and eventually sheds. Autumn is the time to add a scalp oiling treatment to your regimen, using the oil as a buffer to the hair shaft during washing, when most damage occurs.
Water temperature matters, in small but measurable degrees. Hot water strips oil from scalp and skin, particularly those long-chain ceramide lipids from the scalp. The hotter the water, the more oil your scalp and sebaceous glands will produce, which means your hair gets greasy in a few hours. Lukewarm water is gentler on the sebaceous glands and doesn’t send you in the cycle of too much, then too little.
Adjusting Your Cleanser Before You Add Anything New
Foaming cleansers can be harsh on the skin and exacerbate the problem. If your barrier is already in a fragile state, a foaming cleanser with surfactants can further damage it. Therefore, you may want to consider switching to a hydrating, cream-based, or non-foaming cleanser. It effectively washes away the day and pollutants without compromising the lipid barrier that needs to stay strong to keep moisture in.
This is another tweak that takes about two weeks for most people to begin seeing improvement. Your immediate reaction may very well be, “I feel like I’m not getting my face clean”, but you are likely used to your skin’s “I better protect myself and produce even more oil because she’s going to strip it all off again” reaction.
The frequency of exfoliation might need to be reduced as well. Chemical exfoliants, in particular, can be too much for a barrier that’s already struggling. If it’s all just going to seem too complicated for your skin, don’t worry! Most of the barrier fixes you’ll be making will keep your pores clearer and healthier for longer anyway.
The Through-Line Here
Changes in seasons can have a harsh impact on your skin and hair. It’s not like the barrier fails massively, but it degrades slowly and most people only see it when the signs start showing.
If you work towards maintaining a healthy barrier, use occlusives, adapt cleansers, and include scalp protection before the harsh winter sets in, you can break free of that pattern. If you moisturize on top of a sealed barrier, the moisture will actually remain locked in.
