What Exactly Is the Paleo Diet?

Pure paleo

Let’s be realistic: There’s no way to eat a Stone Age diet these days unless you live off the land, hunting, fishing, and gathering from what’s naturally available in the wild.  Few can do that, although it’s not impossible.  I’m going to specify my version of the paleo diet because I’m starting a paleo diet trial soon—a first for me.

How long has man had fire?  Biological anthropologist Richard Wrangham estimates hominins tamed fire and started cooking with it 1.8 million years ago.  So I’m cooking my paleo foods if I wish.

As with my beloved Mediterranean diet, definitions of the paleo diet vary.  The following guidelines are influenced by my review of blogs or websites by Loren Cordain, Julianne Taylor, Robb Wolf, and Kurt Harris.  The first three are closely affiliated with each other, so expect lots of overlap.  It’s simplest to define paleo by what’s not allowed.

What’s NOT Paleo?

Industrial vegetable oils (e.g., soybean, corn,safflower), legumes, dairy, refined sugars, grains, alcohol, and high salt consumption.

What Is Paleo? 

The focus is on minimally processed, in-season, locally available foods.  Many favor pastured, grass-fed beef, free-range chickens, “organic,” and the like.  I guess that’s fine if you can afford it; I choose to spend my money elsewhere.


Meat, fish/seafood, eggs, poultry, and wild game.  Most paleo proponents favor lean meats over fatty ones; it’s debatable. Undoubtedly, our domesticated feedlot animals are fattier than wild game, generally.  Processed meats such as bacon would not be pure paleo, but many paleo advocates allow it.

Nuts and Seeds

Favor those with the best omega-6/omega-3 ratio (2 or 3:1), such as walnuts, almonds, macadamia, and cashews.  Modern humans eat way more omega-6 fatty acids compared to ancient hunter-gatherers.

Fruits and Vegetables

It’s probably best to favor those with lower glycemic index.  Examples are berries, melons, cauliflower, tomatoes, onions, and broccoli.  Most modern fruits and veggies  have been bred for large size and good looks.  Ancient fruits and veggies were smaller and had much more fiber per serving.

Tubers, Roots, Bulbs

These are OK per Cordain, and I agree.  Examples include potatoes, cassava, taro root, onions.  Some paleo proponents exclude potatoes.


Cordain favors oils such as canola, flax, olive. Others mention avocado oil.  Aim for a good omega-6/omega-3 ratio.  Lard is probably OK although obviously processed.

Herbs and Spices

Many of our favorites should be OK.  Wolf says balsamic vinegar is allowed, although processed, like all vinegars.  Vinegar is “natural,” as you might have noticed if you ever walked through an apple orchard with rotting fruit on the ground; you can smell the vinegar.


Undecided.  Note that you can make mayonnaise from olive oil and egg yolk.


Olives?  They’re processed, but I’m inclined to keep them in the mix.  Coffee?  Not paleo, but I ain’t givin’ it up.  Consider limiting nuts to one ounce daily since most of them are high in omega-6 fatty acids.  Fresh foods are more purely paleo than canned or frozen, but I’ll not exclude canned and frozen.  Limit fruit?  Probably: in most environments, they’re available only seasonally.  Diet sodas?  Clearly not paleo, but I enjoy one now and then and don’t see any drawbacks to low consumption.

Steve Parker, M.D.

Update October 8, 2012

I learned today that my version of paleo, by coincidence, is similar to the Hartwigs’s Whole30 plan.  But they allow clarified butter or ghee, green beans, and snow peas.  I include potatoes, but Whole30 doesn’t.

9 responses to “What Exactly Is the Paleo Diet?

  1. Hey Doc there is no reason to continue with canned goods and diet sodas here, it seems that you find the odd indulgence trivial but if you approach the paleo diet this way you will lose one of the key benefits and that is the retune of your sense of test and food reward system back to baseline natural normal.

    After 6 months of no processed foods AT ALL, you would find that a diet soda tastes completely different to you than it does now. This can only be experienced not described, but what tastes sweet and indulgent now will taste like a bubbly chemical soup after 6 months of eating only real, unprocessed foods.

    Its fine if you want to follow the 80/20 rule but you will not truly experience all of the benefits. Just thought I would state that going in.

    I heard it described once as this, if you are allergic to cats and own 30 cats, would you give up 28 cats and keep 2?

  2. Cordain stopped advocating canola and line seed oil years ago. Cordain is very anti-potatoes (saponins, lectins, protease inhibitors, high glycemic load)

  3. Danny, you may well be right. Good points. Even now, a diet soda doesn’t taste very sweet to me, more tart or aciddy or just different from plain ol’ boring water. Maybe I’ll just add lemon or lime to my water. Canned items will often so much salt added that the salt alone disqualifies them as paleo. You reminded me of folks who said I’d lose my sweet tooth if I stayed off all sweets long enough; four months wasn’t long enough and I gave up. I agree with Pierre Dukan that some of us never lose our craving for sweets.

    One of my goals is to compose a paleo-style diet for diabetics that could be used in clinical studies lasting 2-6 months. I suspect that would require several compromises away from pure paleo, to make it acceptable and do-able to study participants.

    Hans, I’d swear I read at Cordain’s website that hunter-gatherers got as much as 20% of calories from tubers and roots. I guess that not the same as an endorsement of that practice, especially given the “anti-nutrients” you mention. My wife has his 2012 “Paleo Answer” on one of her i-devices. I need to read it. I’m in the middle of his 2002 tome now.


  4. Good write up on the paleo diet. I did notice one mistake, you say “Many favor pastured, grain-fed beef”. I think you mean grass fed beef.

  5. Hans, I found a 2011 post at Cordain’s website indicating he has no problem with canola oil: http://tinyurl.com/9qgzwmq