It depends on YOUR version of Primal/Paleo.
It depends on the source of the Greek Yogurt, if YOUR version of Primal/Paleo includes dairy.
Casein and lactose are fairly common sources of food intolerance, so if you haven't already done a 30 days strict paleo, then I would do that first. Then test out how you feel with adding dairy. If you can tolerate dairy fine, then dairy has a lot to offer nutritionally, and yogurt with its probiotics is particularly nice.
There's nothing special about the Greek style, though. It's just yogurt that has been strained so that it is much thicker and has a higher fat and protein content. However, it does taste a whole lot better, in my opinion.
If I could tolerate dairy, then I would absolutely eat it, every day! Too bad, so sad for me...:(
Listen to this Ben Greenfield podcast. He doesn't subscribe completely to the paleo diet because he incorporates diary though.
He basically says that it should be fine in the morning or anytime post-workout for recovery.
If you are doing the elimination version of paleo, you'll want to hold out on dairy until you make sure it works within your diet. Yogurt is probably one of the best dairy options besides grass-fed butter, so if it jives with your needs, go for it :)
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