We know it’s hard to throw products out, but keep in mind that beauty products go bad too. Face creams, serums, lipsticks, and foundations, they are all susceptible to bacteria and germs. Therefore, for how long can we keep them?
Face creams Usually, most face creams, especially those containing drugs, carry expiration date. However, cosmeceutical face creams shouldn’t be kept, in general, for more than 6 months. The acidity of the skin on your fingers can deteriorate the active ingredients of the product that can be contaminated by bacteria. Moreover, other ingredients can degrade when exposed to air or in direct sunlight. As for the care products containing essential oils, they should be kept for maximum 4 months, while the “bio” creams should be use more rapidly as they are more likely to develop microbial growth.
How to store face creams? Keep them in your bathroom cabinet. Also, try to use a spatula when applying cream in order to avoid that the acidity of the skin to degrade the cream. It is a good idea to keep the backing paper on, after opening the cream. 
Foundation It is advisable that a liquid foundation to be hold for 6 months, even though on the packaging is written “12 months”, as the covering properties are easily and quickly altered. As for the compact foundation, this should be kept for 8 months because its oily and dry ingredients offer much more resistance to different external factors. Store your foundation into a dry place, away from light, especially if it has a transparent packaging.
Powder, blush As bacteria cannot develop where there is no water, the recommended shelf life for powder and blush is of about 2 years. A creamy blush might degrade quicker as you might transfer germs into the pot when applying it with your fingers. Therefore, it is more appropriate to use a brush or a sponge when applying them.
Mascara, eyeliner, eyeshadow Usually a mascara can be kept for about 3 to 6 months, after this period it loses efficacy. When used daily, a small mascara lasts for about 2 months. Try to invest in smaller tubes and change them frequently. You should always keep in mind that eye products should me replaced more often as they can cause unwanted eye infections, such as conjunctivitis.
Liquid eyeliners can last for three months, while pencil eyeliners, two years. As for the eyeshadows, those with a creamy texture have a shelf life of 6 months, while the powder eyeshadows, 2 years.
Lipstick, lip gloss, lip balm, lip liner Women usually hold their favorite lipstick until the last small nub. Lipsticks and lip glosses are makeup products very sensitive to light as rays degrade their pigments. Furthermore, lipsticks contain water and this makes them a real source of bacteria. Therefore, keeping in mind that everything you apply on your lips enters directly into your mouth, try to hold lipsticks for about 9 months, maximum 12. Store them into your makeup kit or in the bathroom cabinet. Avoid putting them into the fridge as cold modifies the molecules that allow the active ingredients to penetrate the skin.
Serums Serums should be kept for about 6 months as they are more fragile products that rapidly lose their effectiveness especially those containing essential oils. Some of these serums can be stored into the fridge, but also in the bathroom.
Cleansing lotions Cleansing lotions can be kept for about 9 to 12 months. However, complex cleansing lotions are more fragile and have a shorter shelf life of 6 to 9 months.