"The Selfish Gene" by Richard Dawkins.

"Biology" by Campbell and Reece

"Primal Bluebeprint" by Mark Sisson

"Burn the Fat Feed the Muscle" by Tom Venuto

"The Human Diet" by Rene Endara

"Muscle Chow" by Gregg Avedon

"Catching Fire" by Richard Wrangham

indirectly anything by FA Hayek, but particularly "The Fatal Conceit"

various non-paleo fitness related web sites.

....And tons of self experimentation, trial and error.

I am an economics and mathematics undergrad, so I probably could read better stuff, but this is what I've used to help form my own eating and exercise habits.

I've been a nutrition consultant (and personal trainer/life coach) since 1999. Pretty eclectic background, nutrition-wise.

I was a whole-food/organic vegetarian for 14 years. I read everything I could get my hands on on vegetarian nutrition back in 1982 and even so, was getting sicker and sicker (mostly because of gluten-intolerance.) I started eating free-range/grass-fed meat again in 1997.

I started eating a WAP-inspired diet back in 2009 and went Primal in 2010, reading a lot of Paleo/Primal blogs, Gary Taubes, etc...

WAP and Mark Sisson have been my primary influences.

I am/was all in for all-natural (no added sugar / chemicals) food, with consciously limiting simple carbs. That requires some ongoing research and on its way - found info about paleo.

Till now, the two major diff I found are -

1. no grains and dairy
2. high amount of animal fats, like bacon, tallow.

Level of nutritional knowledge: I'm finishing up an internship in clinical nutrition.

How did I get to paleo? Well, I already disliked the USDA-type diet from casual research I had done before going back to school for nutrition - I was into lifting and fitness generally, and there tends to be a strong bias against the low-protein, high-carb approach. I was frustrated with the idea of low-carb, because even though it made sense to me, I didn't like the idea of pounding CAFO meat and cheese indiscriminately, and I couldn't get over the aversion to fruit and many tubers, or the abuse of carb-free and low-carb frankenfoods. I was starting around that time to warm up to eating locally and sustainably, having rising sentiments regarding the cornucopia of problems with industrial farm-produced food (my husband was getting more into homebrewing, too, which tends to have a local, independent vibe). When I came across paleo, it appealed to me logically, scientifically, and emotionally. I remember it triggering some thought back to an honors anthropology course I had taken that touched on the diet of early man. It just...made sense, on multiple levels.

That's such a reductive version of how it happened, but I suppose those are the highlights, as best as I can discern.

As a side note, out of all of my peers (who are almost all USDA acolytes), the one who accepts my position on diet and nutrition the most fully is our group's localvore vegan (the sort who favors real food over sugar-laden-but-vegan-so-they're-healthy concoctions). The others insist my avoidance of grains is unhealthy. I try to pay him the same respect. Strange bedfellows.

Nutritional barely entered in, though I got diabetes under control with carb exchange counting and I like the Paleo emphasis on eating meat. This was reinforced by a visit to Lascaux where no vegetable products are depicted.

My primary interest in paleo is behavioral. Emulating hunt-and-gather is what it's all about. I'm not a re-enactor with a spear, and I don't like to lift heavy things or run short sprints any more than I have to. I aim to walk 10 miles a day and avoid mechanized transportation as much as I can. That's maybe only 20% of what a true nomadic psleo would do, but I believe it is of more benefit than in eating 100% paleo. Sedentism is the most Neolithic disease.

I had experience with weight watchers and have been constantly trying to keep weight under control for my whole life. Once my parents decided to lose weight (basically weight watchers, calorie restricting) I got to watch a lot of how it worked. Most things I knew about nutrition before reading Cordain's the Paleo Diet and listening to many of Robb Wolfs podcasts (I love those!) and going on MDA (isn't my fav but still good resource) and reading lean gains and listening to Good calories bad calories by Taubes, I learned by watching what happened to myself and family when i ate certain foods. I learnt that when I eat (starchy)carbs, it becomes SO much harder to lose fat and slim down. This is why the food pyramid never made sense to me, even though I understood the reasoning behind it. As soon as I started cross fit I heard Paleo, and immediately downloaded the Paleo Diet book. I have never looked back. Anyway, I'm not an expert, but I'm smart enough to know the govt recommendations for nutrition are a load of crap.

I wonder if OP meant to ask "what was your level?" This is what my frameworks/beliefs were just before I started paleo:

• High GI carbs bad
• Saturated fat bad
• Lots of fiber, whole grains good for digestion
• Plenty of protein good for weight loss (satiating) and for building/preserving muscle
• Lifting weights good (build muscle, burn calories after working out)
• Cardio good (cardio benefits, creates caloric deficit)
• Soy bad (estrogenic effects)

All it took was to shatter a few myths:

• Saturated fat good, not dangerous
• Fiber hinders digestion
• Manually controlling calories in or out not easiest way to get lean

and learn a little about potential dangers of legumes/grains, and I was left with pretty much exactly paleo/primal.

I've always been interested in diet and nutrition, but I always felt eating low fat high carb led to more problems. I was constantly tired and didn't like eating every 4 hours. Being a bio and chem major, I knew there had to be a reason for why I was always tired, and it must be related to the foods we eat. I was kept researching why this could be. I stumbled upon MDA a few years ago, and finally implemented the diet after struggling to find a solution to my dietary problems. Glad I did and ever since Paleohacks, Robb Wolf and MDA have been greatest knowledge sources.