Generally, we schedule production runs so that our products are at most only 2-3 months old when shipped. Not that this matters much.
Traditionally, hair care products often don't carry expiration dates. The assumption is that they will be used within a year or two anyway. However, if kept at room temperature, our products are good for at least two-four years, probably much longer. I have some earlier NANO shampoo that is about 10 years old and it still seems OK, though it has lost volume through evaporation.
BTW, if someone has some half-empty several-year-old version of our products lying around, send it back to us with a note on about when you bought it. We will send you a brand new bottle. We are always interested in the real world stability of our products.
Peter H Proctor, PhD,MD
