Probably the best academic treatment of why modern foods play a role in diseases of civilization.
For me paleo/evolutionary nutrition is a dietary philosophy rather than a diet. What's the difference? A diet implies following certain rules. And rules really just aren't my thing...
Instead, I prefer to use evolutionary science to think about food, which really does not generate rules, but ideas for us to test out on ourselves while in the pursuit of better health.
It's a little more unsettling: wouldn't it be nice just to have the ability to have a little piece of paper with ten paleo rules to follow? People keep trying to do that, but it doesn't work and it does a great disservice. People follow a rule-based paleo diet and don't do well...and they assume that the paleo diet is a bad one.
Sometimes people see me sprinkling salt on my food and ask "Is that OK on paleo? I thought rule #494494 said no salt?" I would agree that our paleolithic ancestors probably didn't eat added salt and some people have seen huge benefits eliminating it. But rapid genetic change is real, and I seem to carry a gene that predisposes me to hypotension and was a possible cause of the episode that hospitalized me last month (the article mentions how such patients often crave unusual salty foods like pickle juice. My own craving lately is Tibetan butter tea). I feel 100% better on a higher-salt diet.
Another perhaps more common genetic variant causes hemochromatosis, which leads to iron overload. A diet high in red meat would probably be problematic for someone with hemochromatosis, but does that mean they should throw out the idea of following paleo?
If paleo is about certain foods or certain ratios, yes, but it isn't. An evolutionary paradigm combined with individualized experimentation can lead to many varied diets that fall under the umbrella of paleo. It's perhaps possible in the future that better genetic analysis will help people decide what types of food are best for them, but for now we have to experiment.
Sometimes people will furtively mention potatoes to me, as if it's a possible crime and they have to insert it into the conversation with surgical precision. Probably some Paleo Fascist told them via Twitter that potatoes are the spawn of the neolithic devils and will cause them to explode, especially when topped with a delicious mix of chives, salty bacon, and luscious sour cream.
So when you see someone on teh interwebs telling you that you must do X or you can only eat one type of Y or if you combine X and Y you will turn into a tribble...ignore it. Some people are doing all meat, others high-carb. Some eating no dairy, others eating mostly heavy cream. You can find people thriving on all these variations. It's confusing to see people do really well on a type of diet that would make you overweight and sick, but that's human variation for you.