The date on each Keto Chow package isn’t an “expiration” date, it’s a “best by” date.
Keto Chow contains various vitamins that are affected by time and oxygen (among other things, but those are the main detrimental factors), along with flavors and protein. The vitamins, in particular, start to lose their potency over time, and eventually, they end up being below the levels shown on the nutrition panel for Keto Chow. So nutrient “X” may be at, say, 130% level on the day it’s packaged, 100% level at 2 years, and 75% level at 4 years (again this is an example to illustrate). It’s not a linear progression and various nutrients have different degradation curves. If you want to ensure that you are getting the exact vitamin levels shown on the Keto Chow packaging, please consume it before the “best by” date. Once it is past that date, some of those vitamins may start to degrade. Because of that, we do not recommend using Keto Chow that is past the “best by” date as your sole source of nutrition for extended periods of time, but otherwise there should be no issue using it. (Around here, we use bags that are past their “best by” date and can therefore no longer be sold, and haven’t had any issues.)