The 3 biggest warning signs are that the scent changes, the color changes, and/or the formula separates.
If your product suddenly has a bad smell or doesn't smell the way it initially did (bc some products just have bad smells, imo) then it's time to throw that bad boy out. Keeping your products away from sunlight, heat sources, and moisture will make them last the longest.
Getting some yellow or browning on your product?...It doesn't mean that your product is completely ruined but it could have made it more potent or weakened the formula. If it was me, I would be grossed out and want to toss that out for sure. The best way to prevent this from happening is making sure all your products are closed tightly.
Lastly, if your formula seems to be separating your product is losing its effectiveness. The exception to this rule is nail polish. Nail polish will naturally separate the longer it sits. Roll the bottle in your hands to remix. Don't shake your bottle to mix it unless you don't plan to apply it right away, this causes air bubbles. If your nail polish doesn't remix or is stringy and thick it's time to toss it too.
Remember using these products could cause irritation and/or breakouts. You don't want that so just let it go. :)
The good news... as long as you take care of your brushes, properly clean and store them, they can last for many many years. I actually own a blush brush that is well over 10 years old and still in perfect shape.
After talking about products expiring and now this I'm really ready to go through all my stuff and throw away anything that isn't up to par. Anyone with me on this?
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