Ishmael.org
Reason articulated!
I am not known for patience and can't argue with vegans. Occasionally, I just state that carnivores have bigger brains and are smarter and walk away. BTW, I am not primal - I eat grains (not too much).
What do you mean by showing off some research as if it's their own? The source is quoted so you can read the research yourself and draw your own conclusions.
What you can do to debate what they are saying on that site is find another peer reviewed research disproving it. And then you can throw that at them and see what they got to say.
Primal Blueprint is not just a diet, it's a lifestyle: sport, sleep, sun... and also stress reduction. Honestly, why do you want to boost your stress levels, speaking with people who are not listening?