I want to stock up on some supplements, and this one website has a buy one get 2 free sale. I am thinking about stocking up, but I just realized that I don't know what the shelf life of most of these things are?

Talon, most supplements have a few years of shelf life - assuming you're not buying something that has been sitting on a shelf for a few years already

Other than that, things like flaxseed, fishoil, your EFA's do have a limited shelf life. They usually have a processing date and a best before date. Also they should be stored in the fridge and they should come in opaque bottles that protect them from light oxidation. These I would suggest buying from a local store/pharmacy where you can check them out.

Nat

All supplements will have an expiry date .. Note that this is for the sealed, unopened product. Once opened, it's best to consume within a year for general vitamins & minerals, less for herbs, and even less as Nat noted (4 - 6 weeks) for EFA's and nutritional oils. You can also store fresh oils (flax, hemp, pumpkin seed, nutritional blends such as Udo's, Omega 3-6-9 etc) in the freezer to extend their life after opening. No they don't freeze solid ... they just get thicker

Minerals (calcium, magnesium, zinc, chromium etc etc ...) will deteriorate over time and exposure to heat, moisture and light. Same for many herbal capsules and amino acid supplements. These will often state on the label to store in a cool dry place. So, if your kitchen or medicine cabinet or wherever tends to get very warm and/or damp ... you'd be wise to choose another place for storing ... such as a cool pantry or even the fridge, especially in summer.

Doreen