Per FDA guidelines, we stamp the date of manufacture on each bottle, which shows you the exact date the vitamins were produced.
The vitamins and supplements are at 100% potency for the next 2 years.
After the 2 year period, the potency goes down about 10% each year after that date.
All vitamins start to break down the day they are manufactured. Vitamins deteriorate at different rates, so manufacturers will beef up the strength of some vitamins that tend to deteriorate faster, in order to hit the listed strength at the time of expiration.
If you were to purchase vitamins on the day they’re manufactured, ( Born on date) in some cases you’re actually getting a higher strength than what’s listed on the label (to allow for deterioration over time).
Many expiration dates are also padded to factor in such things as shelf time and shipping time.
Stored properly, vitamins can last four or five years, although the conservative recommendation is that they can easily last two years. Fish Oil is not recommended after the 2 year expiration date.
Taking vitamins beyond the "expiration date" is generally considered safe. The only difference is that you may lose potency over time, so taking extremely old vitamins may not give you the desired results that you’re trying to achieve.