Importance of checking and following expiration dates of cosmetics

Many people tend to keep cosmetics for several years until they are used up, but this may not be a good practice. Using cosmetics that have expired or exceeded their shelf life can result in skin problems and contact dermatitis. Therefore, it is important to check the expiration date of cosmetics, starting with the product label.

Cosmetic companies set the expiration date for each product after undergoing an experiment in consideration of the container or product characteristics. The expiry date is usually specified on the back of the product or on the case, and in the case of a tube container, it is also engraved in relief. It is usually printed with 'Expiration date XX year X month'. If it says 'Expiration date: Separately printed', you should look for the separately printed part. Some products are shown in pictures. If '6M' is written on the picture of the cosmetic lid open, it means to use it within 6 months after opening.

For cosmetics that are over three years old and where the expiration date cannot be found, it is highly recommended to dispose of them. Cosmetics containing a large amount of ingredients sensitive to oxidation, such as vitamins and enzymes, usually have a shelf life of 24 months or less, and products that do not have a shelf life of 36 months or less. It is especially important to consume lipstick, lip gloss, lip balm, mascara, and eyeliner within 6 months. Cosmetics are composed of water and fat, which is a good environment for bacteria to grow, and lip products and eye products are frequently exposed to the air, making them susceptible to bacteria.

It is also important to keep cosmetics clean, especially eyeliner and mascara, as they come in direct contact with the mucous membrane of the eye. The shelf life of lotions and skins is generally 2 years before opening and 1 year after opening. To ensure the longevity of the product, it is best to store it in a cool and out of sunlight. Essence is a product made with highly concentrated nutrients, so it is recommended to use it within 6 months. Creams, on the other hand, have a shelf life of two years from the date of manufacture, and it is hygienic to use a spatula (cosmetic spatula) rather than hands.

The shelf life of sunscreen is generally 2-3 years before opening and 1 year after opening, and it is important to store it in a cool place with the lid tightly closed. The shelf life of makeup base or foundation is 2 to 3 years before opening and 1 year and 6 months after opening. If lumps or color changes occur due to prolonged use, it is highly probable that the product has deteriorated and should be discontinued.

Lastly, if there is something wrong with your cosmetics, it is better to throw it away even if the expiration date has not yet passed. Signs of damage include foul or sour smells, separated layers, fragrance and color changes, and hardened contents. It is important to keep in mind that using damaged cosmetics may result in skin troubles and contact dermatitis. To keep track of the date of purchase and opening, you can put a sticker with the date and write it down.