Yes, they may be well-preserved for a long shelf life, but only for the first 2-3 years BEFORE they are opened. And the older the product, the less effective its actives and preservatives will be. Once opened, preservatives may only work for another year. Furthermore, every time you open the lid to use it, you introduce new bacteria, which requires working, active preservatives to dispel these growing nasties.
Adverse skin reactions such as pimple breakouts, rashes and skin/eye irritations and infections are very common occurrences from using outdated cosmetics.
Put simply - every time you use these products on your eyes, lips and skin, you also get an upload of toxic bacteria or fungi... EEK!
Cream based formulas, such as moisturisers, creamy foundations, blushes and eyeshadows are the most prone to bacterial invasion, due to their oil and water emulsion.
Besides the bacterial risk in using old products, there are additional potential irritants from actives that begin to separate as the emulsion breaks down! (which you may or may not be able to see). This poses a risk of any active ingredients no longer being evenly distributed. If you apply this to your skin, you're more than likely applying high concentrations of ingredients that can cause a reaction - eg. glycolic acid, retinol (Vitamin A), even SPF chemicals.
Very recently I met up with a friend who had done just that. Having run out of their usual BB cream, they had grabbed an old half used tube of suncream and woke up the next day with a massive unsightly breakout, which lasted days and could not easily be covered up with makeup, much to their dismay and embarrassment, especially being in the public eye day to day. In a nutshell, this product would have been prolific with bad bacteria and possible separation of SPF chemicals contributing to the redness and breakout.
Of course, natural products are even more prone to perishing, separation and contamination. So ideally, we encourage you to use them up within 3-6 months (up to 12 months for some), store them out of sunlight, heat & humidity and always wash hands before applying. Ultimately, most people now prefer to use natural ingredients on their skin where possible.
iSHiKi-SKiN products are always freshly batched, offering you one of the freshest cosmetic choices on the market, using an effective broad spectrum natural preservative system. Most of our products are dispensed via pumps and sprays, to keep them as fresh as possible and reduce unnecessary contamination from air/finger contact. Our mineral makeup powders can last indefinitely as their inert mineral content cannot harbour bacteria - only on the brushes you use, so be sure to wash those regularly!0