## Which Products Suffer from Humidity **Perfumes.** Even if the bottle looks airtight, heat and humid air disrupt the structure of aromatic molecules, causing the scent to weaken or change. The best place for perfumes is a cool, dark cabinet or dresser. **Nail Polishes.** Regular exposure to the bathroom leads to changes in the consistency of the polish, making it thick, evaporating solvents faster, and deteriorating the quality of the coating. It is better to store such products in a dry place in a cabinet. **Active Serums (Vitamin C, Retinol).** These ingredients are extremely sensitive to light, heat, and humidity — under such conditions, they oxidize and lose their activity, making the care less effective. A cool dark place or a cosmetic refrigerator is the preferred storage option. **Sunscreens.** SPF filters are unstable with temperature changes; due to heat and humidity, the product may lose its ability to protect the skin from ultraviolet rays. This is confirmed by dermatologists who recommend storing them in conditions with moderate temperature outside the bathroom. **Tools (Brushes and Sponges).** Constant humidity creates an ideal environment for bacteria to multiply, increasing the risk of irritation or breakouts when using contaminated tools. Dried and clean brushes should be stored in a well-ventilated dry place. **Dry Decorative Cosmetics (Powders, Eyeshadows).** Increased humidity leads to clumping of particles and deterioration of texture, making the products less convenient to apply. **Masks (Sheet and Hydrogel).** Moisture exposure reduces the concentration of active components, so it is better to store them in a cool place or even in a cosmetic refrigerator. **Natural Cosmetics.** Products with minimal preservatives spoil faster in high humidity conditions, which can lead to the development of microbes. Their optimal place is a dry dresser or cabinet in a room. **Decorative Cosmetics with a Short Shelf Life.** Mascaras, liners, pencils, and lipsticks retain their properties longer in a cool place rather than in a humid bathroom, where their shelf life shortens faster. ## Where to Store Cosmetics Properly Cosmetic care specialists recommend placing products in cool, dry places with minimal temperature fluctuations, such as on a vanity in the bedroom, in a dresser drawer, or a separate cosmetic cabinet. This helps maintain the activity of ingredients, prevent the development of microbes, and extend the shelf life of products. Similar recommendations are also found in foreign sources: experts note that constant humidity and heat in the bathroom can accelerate the decomposition of active substances and promote the growth of bacteria, negatively affecting both the products and the skin when used. ...Although the bathroom seems like a natural place to store cosmetics, as this is where most people wash their faces, apply skincare, and do makeup, the typical conditions of this room — high humidity, temperature fluctuations, and heat — can negatively impact the state of products, shortening their lifespan and reducing the effectiveness of formulas. This issue is confirmed by the recommendations of cosmetic storage specialists, who advise keeping active products away from moisture.