Since the start of FastPaleo.com, we have welcomed both Dairy and Non-Dairy recipes. More important than the question of whether dairy is technically a “paleolithic” food or not is the question of “Is dairy healthy to eat?”
The first part of the answer is related to what kind of dairy you get: non-pasteurized dairy from grass-fed cows is a completely different food product than pasteurized dairy.
The second part of the answer depends on individual tolerance. This is not a matter similar to how well you tolerate a traditional “non-paleo” food, like say wheat or processed sugar. The difference is there is almost nothing nutritionally redeeming about either of these, whereas dairy can be very good for you, if you tolerate it well.
FastPaleo.com has always aimed to be as inclusive as possible. We cannot forget that the health problem in the US is enormous, and the more ways we can get people eating more paleo/primal, the better. This is the same reason we welcome so many great “paleoized” treats on the site—people need better alternatives.
Getting back to dairy, we do also understand that definitions and rules are important, particularly for people starting out who need clarity. So we offer the same advice many do: try eliminating dairy from your diet. Then, reintroduce it. If you notice indigestion, bad skin, increased mucous or other unpleasant health effects, then dairy is likely not part of your “paleo.” If you reintroduce it and feel great with no adverse health effects, then it is likely “paleo” for you.
Dairy is one issue where we strongly encourage an individual definition of “paleo/primal”