If you see a "6M" or "12M" on a cosmetic product, then you'll know how many months you can use it for after opening.
But crumbling texture, strange odour and itchy skin are often the first signs that cosmetic products have expired.
Makeup, just like food products, has an expiration date.
And yet, many of us tend to only throw out lipstick, mascara or foundation when they are empty or something is clearly wrong with them.
There are clear signs you should be able to recognise to see that a product should no longer be used, since there are health risks in play.
There are also ways you can extend the shelf life of your cosmetics.
How to recognise expired makeup
The shelf life of cosmetic products depends heavily on their formulation and consistency.
"With liquid products like foundations, you often see the texture separating or the product becoming lumpy," says makeup artist Lukas Wythe.
A rancid, pungent or "chemically altered" smell is also a clear warning sign.
If the colour has changed, for example in a powder or blusher, you'll also want to throw it away. Of course, if your skin gets itching, burns or looks red after applying, the product should be binned right away.
Read more: Ask The Expert: Tips and tricks to make your makeup work for you
Health risks from old cosmetics
Expired makeup products pose health risks to your skin, but more than that, they have precisely the opposite effect of their intended cosmetic purpose.
"In addition to skin irritation and allergic reactions, they can promote blemishes and spots because bacteria multiply in the product," says Wythe.
Using dirty brushes further spreads germs across your face and reintroduces them into the product.
According to the expert, the eye area is particularly sensitive, and expired mascara, for instance, can quickly lead to irritation or infections.
What to do with old makeup products?
Products that are visibly spoiled or have been used well beyond the recommended time frame should be disposed of with your general waste.
This is because materials like plastic and metal are frequently glued together.
How to extend a product's shelf life
To extend the lifespan of your products, hygiene is key.
This includes regularly cleaning brushes, using products only with clean hands, and closing jars immediately after use.
Another tip is to avoid storing makeup in the bathroom. Heat and humidity affect the ingredients and accelerate their breakdown.
A cool, dry place, such as the bedroom, is much more suitable, according to the expert.
Read more: Ethereal vibes, blurred lines, ‘cloud’ skin: Try out these top makeup trends
What does the jar symbol on products mean?
In Europe, most products feature a small symbol of an open jar with a time indication, such as "6M" or "12M".
This refers to the recommended period of use after opening.
"Even after the indicated time has passed, a product is not automatically bad – as long as it shows no abnormalities," says Wythe.
The period-after-opening symbol is required in the European Union, but the US does not require cosmetics manufacturers to display a product's shelf life.
If in doubt, checking the smell, colour and consistency can help determine whether a product is still usable. – dpa
