When the heatwave arrives, not only do we change our wardrobe, but our skin’s function also undergoes radical changes. You’ve probably noticed that the creams that worked well in cooler months suddenly feel “too much” in summer, your face gets shiny faster, unexpected pimples appear, or strange, dehydrated patches develop on your skin.
This is not a coincidence, nor is it the fault of your cosmetics! Serious biological and physical processes are happening behind the scenes. Let’s explore together how heat and sunlight transform your skin’s chemistry and what you can do to maintain the perfect balance!
1. The relationship between sebum production and temperature
Let’s start with the most noticeable summer phenomenon: increased skin oiliness and enlarged pores.
The sebaceous glands in our skin (glands that produce silky lipids) are extremely sensitive to temperature changes. It is a biological fact that with every one-degree Celsius increase, sebum production rises by about 10%.
In summer, sebum becomes more fluid due to the heat. This thinner oil mixes more easily with dead skin cells, airborne dust, and makeup residues, which leads directly to clogged pores and the formation of blackheads and pimples.
2. Sweating and skin pH
While the sebaceous glands are working overtime, the sweat glands also activate to cool our body. Sweating is essential for temperature regulation but can cause serious trouble on the skin’s surface.
- Weakening of the acid mantle: Human skin’s natural pH is slightly acidic (ranging between 4.7 and 5.75). Sweat contains sodium, potassium, and lactic acid, which changes the skin surface’s pH, shifting it toward a more alkaline state.
- Dehydration and TEWL: Although sweat makes our skin feel moist, it actually causes water loss. Warm air and air conditioning accelerate transepidermal water loss (TEWL), meaning water evaporates from the deeper layers of the skin. The result? Skin that is oily on the surface yet deeply dehydrated and tight.
Tip: If you want to learn how to balance this dehydrated state with the right active ingredients (like hyaluronic acid and centella), read our detailed guide titled “3 Active Ingredients Your Skin Needs in Summer”!
3. UV radiation and oxidative stress
The most dangerous enemy of summer skincare is undoubtedly sunlight, specifically UVA and UVB rays.
When UV light reaches your skin, it triggers the formation of free radicals. This oxidative stress directly damages skin cells and breaks down collagen and elastin fibers responsible for firmness (this is called photoaging).
Additionally, UV radiation causes the outermost skin layer to thicken (hyperkeratosis) as the body tries to protect itself from sunburn. However, this thickened layer traps sebum even more easily, often intensifying acne symptoms by the end of summer.
How to adjust your routine for summer skin function?
Now that you know the biological reasons, you can see that a completely different approach is needed in summer:
- Lighten up textures: Swap heavy, occlusive creams for light, water-based gel creams to avoid clogging pores.
- Double cleansing every evening: An oil-based cleanser is the only one that can effectively dissolve the thicker, altered summer sebum and waterproof sunscreens.
- Antioxidants and SPF: Use a vitamin C or green tea serum under your sunscreen in the morning to neutralize free radicals caused by UV rays.
FAQ – Frequently Asked Questions
1. If my skin feels oilier in summer, can I skip the moisturizer?
Never! If you skip moisturizer, your skin will produce even more sebum to compensate for the lack of water. Instead, switch to an ultra-light gel with hyaluronic acid or beta-glucan.
2. Why do I get pimples from sunscreens?
This is a common problem, but it’s not the sunscreen itself causing it—it’s improper cleansing. Physical and chemical sunscreen filters cannot be completely removed with regular water-based cleansers. Use an oil-based cleanser first!
3. How can I soothe my skin after a long day outdoors?
Avoid active ingredients (retinol, exfoliants) at such times. Choose soothing products containing panthenol, ceramides, or Centella Asiatica instead.
Help your skin easily survive the heatwave!
Preventing summer skin problems starts with creating the right, light, and protective routine. Don’t let heat, sweat, and UV rays take control of your face! Choose from our latest Korean skincare products designed specifically for summer.
