It became known what will happen if you leave a makeup bag in the car during the summer.

      Many drivers and passengers keep tubes of cream, bottles of foundation, or lipsticks in the glove compartment or cup holder—to refresh their makeup right before getting out of the car. However, as technologists explain, this habit can compromise the effectiveness of cosmetic products, and the damage often goes unnoticed.

      The main problem is the high temperature, which in a closed car during summer significantly exceeds outdoor temperatures. Even a few hours in such conditions is enough for the sensitive components of skincare cosmetics to start breaking down. This primarily concerns vitamin C, retinol, certain peptides, and antioxidants—they lose their activity when overheated for extended periods. Externally, the product may look perfectly fine, but the expected effect from its use will no longer be there.

      The situation is no less serious with sunscreens. Many leave SPF cream in the car to use it before a walk or a short trip. However, constant exposure to high temperatures affects the stability of the filters, which means the level of skin protection is compromised. The solution is simple: such products should be stored at home and taken with you just before use.

      High temperatures affect not only the active ingredients but also the physical structure of cosmetics. Creams can separate, oils can change consistency, and decorative products, including lipsticks, cream blushes, sticks, concealers, and foundations, can melt. Even if the product returns to its usual appearance after cooling, its formula may not have fully recovered. Changes at the level of emulsions or active components are often not visually apparent.

      Technologists advise paying attention to three signs: whether the smell, color, or texture has changed. If the cream has become uneven, the serum has clouded, or there are oily droplets on the lipstick—such a product should no longer be used.

      By the way, danger does not only come from summer heat. In winter, cosmetics often remain in the car in freezing temperatures and then suddenly enter a warm environment. Constant temperature fluctuations, according to specialists, also disrupt the structure of emulsions and shorten the shelf life of many products.

      Particularly cautious should be those with natural cosmetics and products with minimal preservatives—they are less stable under extreme storage conditions and require more careful handling. As noted by Maria Verichenko, head of the Sokolov Beauty division, the most common mistake is thinking that cosmetics only spoil if they literally melt. In reality, changes begin much earlier and are not always immediately noticeable.

      Experts agree on one thing: a car should not become a permanent storage place for skincare and decorative products. If cosmetics are needed throughout the day, it is better to take them with you in a bag rather than leaving them in the cabin, and this should be done regardless of the season.