Seasons
Switching Your Routine For The Season
What genuinely needs to change between January and July, and what is marketing.
Published 2026-09-01 · 8 minute read · The Gelagen Journal
The advice to "switch your routine for the season" is sold every spring and every autumn, and about half of it is real. Here is which half.
What Genuinely Changes
Humidity, and therefore water loss
Cold outdoor air holds very little water, and indoor heating dries the air further. Your skin loses water faster in January than in July, and that is a physical fact rather than a marketing claim. It is the strongest argument for a richer moisturiser in winter.
Sebum production
Sebum output rises with temperature. Skin that is comfortably balanced in April can be shiny by July and tight by December, without anything about you having changed.
Ultraviolet intensity
UVB, the burning wavelength, varies enormously with season and latitude — which is exactly why vitamin D synthesis stops for months at northern latitudes. UVA, the ageing wavelength, is far more constant and passes through cloud and window glass. This is why sunscreen is not a summer product.
Behaviour
Hotter showers, more indoor heating, less fresh produce, less daylight, more alcohol in December. Several of the things people attribute to "winter skin" are actually the winter version of their own habits.
What Does Not Change
Your skin type. Dry skin does not become oily in July; it becomes dry skin in warmer weather. Buying a full second routine on the assumption that you have transformed is how people end up with a cupboard.
The need for sunscreen. Daily, all year.
The fundamentals. Cleanse, moisturise, protect. The season adjusts the textures, not the structure.
What To Actually Change
| Winter | Summer |
|---|---|
| A richer, more occlusive moisturiser | A lighter one, gel or fluid |
| Shorter, cooler showers | Same, and rinse chlorine off promptly |
| Cleanse gently, possibly water only in the morning | A slightly more thorough cleanse if you are sweating |
| Consider a humidifier in a heated bedroom | No equivalent need |
| Sunscreen daily, especially in snow | Sunscreen daily, and reapply outdoors |
| Watch vitamin D, which your skin cannot make | Sun exposure covers it, without burning for it |
How To Make The Switch
Not all at once. Change the moisturiser first, live with it for two weeks, and see whether anything else genuinely needs adjusting. Most people find it does not, which saves them money and saves their barrier a shock.
The seasons to be careful in are the transitional ones. Early spring and early autumn are when the air changes faster than habits do, and when the most reactions turn up in dermatologists' waiting rooms.
The Nutritional Season
One nutrient on our panel has a genuinely seasonal story and the rest do not. Vitamin D synthesis stops between roughly November and March above 37 degrees of latitude, regardless of how much time you spend outdoors, because the wavelength does not reach the ground. Everything else on the panel is a matter of what is on your plate rather than what is in the sky.
What does change seasonally is diet. Winter eating narrows: less fresh produce, more convenience food, more of everything except vegetables. That is the honest seasonal case for a nutritional floor, and it is a modest one rather than a dramatic one.
Questions
Quick Answers
Do I need two complete routines?
No. Most people need one routine and two moisturisers. Buying a second set of everything is the expensive way to solve a texture problem.
Is sunscreen really needed in winter?
Yes. UVA is comparatively constant year-round and passes through cloud and glass; it is the wavelength most associated with visible ageing.
Why does my skin get worse in autumn?
The air dries out faster than habits adjust, and transitional seasons are when barrier problems most often surface. Move to a richer moisturiser before you need it.
Journal