All summer we spend on sunscreen, hats and shade, and then we walk into an office with the air conditioning at twenty-one degrees and there, over those eight hours, the skin loses the battle. Dermocosmetic experts say the damage from air conditioning is no smaller than the damage from the sun - it is just quieter, so nobody pays it any attention.

The mechanism is simple. Air conditioning dries the moisture out of the room's air. The skin gives up its own water into that dry air and tries to compensate. The result is dehydrated skin, lost glow, higher sensitivity and a damaged barrier. Raquel Gonzalez, a cosmetologist by profession and creator of the Byoode brand, lists the factors: reduced humidity in the space, temperature contrasts with the outdoors, and less oxygenation of the air indoors.

A fan is not a solution, it is the same trap under a different name. Pharmacist Carla Pires puts it directly: fans, fixed or portable, encourage water to evaporate from the skin's surface. So the thing giving you relief in the moment is prolonging the same loss.

What is practically recommended is neither expensive nor complicated. First - the air conditioning must not blow directly at your face, especially towards the lips and eyes. Second - formulas with hyaluronic acid, glycerin, panthenol or aloe, which hold water in. Mireia Fernandez of Perricone MD explains that hyaluronic acid of varying molecular weight acts like a sponge attracting water.

Third - the texture should be a summer one. Estefania Nieto of Medik8 recommends gel-creams with squalane or a low concentration of shea butter. A heavy winter cream in August is not care, it is discomfort. And fourth, for those who want to go further: niacinamide, vitamin C and retinoids give additional protection from thermal stress, as Gonzalez says.

Now the part the industry says loudest. Marta Agusti, nutrition director at Advanced Nutrition Programme, recommends dermocosmetic supplements rich in hyaluronic acid, ceramides and omega 3 - hydration from the inside. That is not nonsense, but notice where every piece of advice leads. The Medik8 cream from the article costs 189 euros. Perricone MD - 78 euros. Byoode - 69.

In other words: the advice is correct, and the bill is steep. The basics - do not aim the air conditioning at your face, drink water, apply something that holds moisture - cost almost nothing. Everything above that is a choice, not a requirement. Do you need a 189-euro cream for skin that sits in an office, or do you need the air conditioning not to be pointed at you for eight hours?