I've become a skeptical learner of Paleo/Primal nutrition
I think a lot of stuff that is talked about as 'nutrition fact' in this community is way overblown. For instance, say I wanted to avoid phytates. Logic says to avoid beans and grains, right? I don't think eating grain really leads to nutritional deficiences. Well if I replaced my white rice with yam, I'll be getting way more phytic acid in my system. Lectins? They're in almost everything. I DO believe gluten, casein, and lactose are problematic. They give me stomach aches. Beans don't have any of that, so I would think they could be fine. However, their fiber content is tremendous, and fiber clogs up your drain like expanding rice in a pidgeon. I DO believe GMO's are deadly, that organic is better, that high fat (even saturated) is good, red meat is great, and organs should be eaten. I DO believe eating things that are already processed for you is bad if eaten as a staple (these things contain added sugar, polyunsaturated or trans fats, food coloring, etc).
I think it's eating grain INSTEAD of other foods that leads to deficiencies. Grain is only seen as a cause because you can't eat both (grain and mineral/vitamin rich foods) without being rich or full of time.
I guess what I am saying is that I don't agree with the explanations given to us on 'why' certain things are bad. There are other possible (even simpler) explanations for some things. I read that early farmers had mineral deficiencies because they got all their food from one field where naturally the soil will be deficient in something. Earlier peoples that hunted-gathered were getting food from a wide range of land, so they spread out their source of minerals.
All I can say for sure is that nature will provide. (If we get out of its way).