TAMPA, FL (WFLA) —  Like the products in your refrigerator, the ones in your shower have a shelf life. Wesley Chapel salon owner Johanna Amarante says products like shampoo and conditioner are considered expired after two years.

“Whatever ingredients that product has in it will no longer do the job like its supposed to,” Amarante says.

She says if you find a salon-quality product for sale at a discount retailer, it’s probably expired. She explains that buyers get a hold of outdated stock, sell to retailers, who add their own sticker with a bar code.

Another sign of an outdated product is the packaging. Manufacturers update packaging when they reformulate the line.

“Every time they transition to a new style – a different look – the ingredients have changed,” says Amarante.

More concerning to many people looking for a bargain, is that occasionally salon owners who go out of business sell their high-quality stock to a buyer, who will dilute it. The product may be diluted with alcohol, which can strip hair color and cause damage to the hair, or water, which can dilute the pure ingredients from the product, making it less effective.

When your color fades or your hair frays – it’s stylists’ reputations that have a bad hair day.

“Your doctor knows what’s wrong with you – they diagnose you, and give you a prescription. It works the same way in the beauty industry. We work with your hair. We know what to recommend for your hair,” says Amarante.

Some manufacturers have been fighting what’s known as the “gray market” – the reselling of outdated products, the dilution of products, or counterfeited products, for years. Redken and Pureology, for example, have processes for identifying products sold through unauthorized retailers.