The dates on a cosmetic assume reasonable storage. An Indian summer on a bathroom shelf is not that.
What actually destroys them
Heat, which separates emulsions, softens balms and degrades active ingredients faster than time alone.
Light, which breaks down many formulations — which is why so many come in dark or opaque packaging in the first place.
Humidity, which is why a bathroom is the worst room in the house for them despite being where everyone keeps them.
Air, once opened, which is what the open-jar symbol is about.
What to do instead
- Cool and dark — a bedroom cupboard beats a bathroom shelf every time
- Upright, so a cap or pump does not leak
- In the original carton where there is one, because it blocks light and carries the batch code and dates
- Not in a car, ever, which is where products cook
- Sealed items left sealed until used
Dates
Note when you open something. The open-jar symbol gives a period after opening, and it starts when you open it — not when you bought it. Writing the date on the carton takes five seconds and is exactly what makes an honest listing possible later. Describing beauty products.
What it costs
Nothing, except moving things out of the bathroom.
Questions people ask
Does refrigerating help?
For a few products it is recommended on the pack. Otherwise a cool cupboard is enough.
Is a product past its date unusable?
Not necessarily, and it must be declared. Decide with the date in front of you.
What about decanting into smaller pots for travel?
For your own use, your choice. Never for resale — it destroys the batch code and the dates. Common mistakes.