Like most consumer products on the market today, your skin care essentials have a shelf life. And while a product’s lifespan can vary from six months to two years or more, its long-term efficacy ultimately depend on its ingredients, packaging and storage.
With the exception of many natural and organic options, skin care products are formulated with a combination of preservatives that help provide a broad, balanced spectrum of effect against bacteria, yeast and mold fungi. However, when a product is opened, air and bacteria may begin to gradually degrade the ingredients, thereby lessening its efficacy. Factors such as sunlight, heat and humidity may also cause degradation.
Certain ingredients are inherently vulnerable to the effects of heat or sunlight. For example, some forms of antioxidants vitamin C and E are highly unstable, as are ingredients such as glycolic acid, retinol and hydroquinone.
Currently, the FDA does not require expiration dates for cosmetics. Over-the-counter drug products including sunscreens and acne monograph products do require expiry dating. Most manufacturers perform stability tests on their cosmetic products, in which case a “use by” date may be provided.
The European Commission Cosmetics Directive does not mandate a “best by” date on products with a shelf life of 30 months or more; instead, companies utilize the “period-after-opening” symbol, which indicates the number of months that a product is safe for use after it is first opened. This time frame may be shortened by improper storage, such as when products are kept in a steamy bathroom.
Protect your products by keeping them firmly closed and away from direct heat or sunlight. Wash hands thoroughly before dipping into a product to prevent the spread of bacteria; many products also come with disposable or washable applicators that can help to reduce bacterial contamination.
Look for lotions or serums that come in an airtight pump to maintain ingredients’ purity. Products such as SkinMedica® TNS Essential Serum® feature dual-chamber dispensers to separate key ingredients prior to use and better preserve their potency.
Lastly, to determine if a skin care product’s days are numbered, use this common-sense rule of thumb: If you notice separation, discoloration or a strange odor, it’s time to toss.