Research Claims Paleolithic Man Ate Zone Diet

Kuipers et al, “Estimated macronutrient and fatty acid intakes from an East African Paleolithic diet” British Journal of Nutrition Online first printing Sep. 23rd, 2010.

The canonical “Zone” diet promoted by Barry Sears calls for 30% of calories from protein, 40% from carbohydrates, and 30% from fat. These Rx’d targets are subject to slight variation depending on individual needs, but according to Sears, the range of hormonally optimal ratios of protein/carbs run from 0.6 to 1.0, and higher levels of fat are acceptable for athletes and others whose energy expenditure is particularly high.

This paper, by researchers from the Netherlands, Britain, and America (the authors include Paleo-guru Loren Cordain) attempts to model a variety of hunter gatherer diets based on a database of available East African foodstuffs. The study argues that Paleolithic humans ate a diet that was composed of approximately 25-29% protein sources, 39-40% carbohydrates, and 30-39% fat.

Dudes, that’s the Zone.

If I were Barry Sears I would be jumping with joy today.

Beyond 30 days of “100% Paleo”

I’ve been eating an 80/20 (or even 90/10) “Primal” diet for a long time; well over a year, in fact. I began eating what I termed a “flexible-Paleo-Zone” diet in August, 2009. And I’ve read and studied “paleo” ideas of nutrition during all of that time, becoming something of a nutrition nerd. In the time since I started this process, I’ve given up alcohol for extended periods, and I’ve eaten more cleanly than just about anyone that I know, on average. But I’d never gone, you know, 100%. While others had “suffered” through giving up every prohibited paleo food, I had allowed myself flexibility and compromise.

Coming out of this summer, I felt that something was different. Something made me want to start fresh again this fall. I wanted to cleanse myself, and so I decided that maybe it was time for me to try a period of super-strict paleo dieting.

So, on August 22nd, I began my 30 day cleanse, a period of “100% paleo” nutrition. The plan was simple: kick start my semester, disrupt any bad patterns of eating I may have set for myself over the summer, and force myself to be a bit more creative with my cuisine. I hoped that the end result would be to reinforce all my best primal instincts with regard to nutrition. Mission accomplished. I got all of that, and more in the bargain.

The Details of My “100% Paleo” Diet

My diet, like the plan itself, was pretty simple.

Completely prohibited: sugar, alcohol, grains, legumes, dairy, and industrially “processed” or “packaged” foods, i.e. foods with lots of ingredients or industrially processed ingredients. No seed or bean oils or processed vegetable oils high in PUFAs, or foods fried in them.

Encouraged foods: anything whole, unpackaged, naturally produced, organic, local, minimally processed.

I did a lot of cooking; I carried my lunches; I didn’t eat out too many times. I chopped a lot of veggies. I would start my day with veggies, and ate veggies typically at every meal.

There was one not-really “paleo” structural restriction I imposed on my eating habits, which was that I restricted my feeding period to around 12 hours a day, between 8:00 am and 8:00 pm. This is basically a very moderate and mild form of “intermittent fasting.” Because I train in the morning, usually at 6:00 am, this meant that I was training in a fasted state.

My diet was a low-carb diet, meaning that fruit and starchy vegetables were somewhat restricted, or at least not preferred sources of calories. I would estimate that my daily carb intake ranged and varied from 50 to 150 grams a day; I really don’t think I did more carbohydrates than this at any time.

It was a very high protein and high fat diet, meaning that I allowed myself to eat protein sources (meat and eggs) virtually ad-libitum, and frequently indulged in high-fat foods like coconuts, avocado, and nuts during my eating window, if I felt hungry. I would estimate that I regularly ate over 200g of protein and 200g of fat per day. Altogether, probably I averaged between 2800 and 3200 calories per day.

It was a post-Zone diet, meaning that, at every meal I tended to always eat a combination (not to say a balance) of protein sources (i.e. meat and eggs), carb sources (green veggies, roots, fruits), and fats (nuts, naturally occurring and rendered animal fats, avocados, olive oil, and coconut oil). My post-Zone eating pattern is based on the tweaking of Zone eating first advocated by Robb Wolf, who pioneered the transition from Zone to Paleo-Zone cuisine when he was the official CrossFit nutrition guru. Robb essentially advocated a higher fat, lower carb version of the Zone, but he continued (and continues) to recommend a kind of balance of macronutrients be consumed at every meal.

The only supplement I used was fish oil (usually a tablespoon a day, yielding about 5.4g of Omega-3s). The main processed foods I allowed myself were unsweetened non-alkali cocoa powder, coconut butter, coconut oil, and olive oil.

For breakfasts I would eat 2-3 eggs, a bunch of bacon (always nitrate free) or occasionally some other meat, sometimes some smoked salmon. I usually ate greens with my breakfast, sometimes as my only carb, other times balanced with some squash or sweet potatoes, and small quantities of fruit. I would fry things in bacon grease.

I would drink coffee with breakfast and afterward, always black, but sometimes flavored with some unsweetened cocoa powder. My goal was to stop drinking coffee after noon. I didn’t always stick with that plan, but when I did, I was grateful for the better sleep that followed.

For Lunch, it was usually leftover dinner meats and dinner veggies. Maybe some nuts, usually some olive oil, occasionally some coconut oil. Sometimes a piece of fruit.

For dinner, lots of meat (wild, local, grass fed, free range and pastured pork, chicken, beef, bison, salmon, etc.) some more veggies, such as greens, cabbage, broccoli, squash, asparagus, etc., and plenty of olive oil or other source of fat.

After dinner, before 8:00 pm, additional protein or fats, like coconut butter, cacao nibs, almond butter, nuts. If I felt like having carbs, some small servings of fruit. Then, lots of water and tea.

The Aftermath

I maintained my weight over the course of the month, which was my goal. But I think, at least my scale suggests, that I lost 1.5 pounds of fat and gained 1.5 pounds of muscle. I’d like to think that I’m looking better. And except for my crappy performance in the Half Marathon, which I won’t blame on Paleo eating, I think I’ve had a good month in the gym. Bottom line is: I like how 30 days of “paleo” made me look and feel and perform. I look, and feel, and have performed at least marginally better than I was performing on my “flexible-Paleo-Zone” eating plan.

During past periods of privation, I’ve planned elaborate and gut busting cheating sessions. And as dedicated readers of this blog know, I love to describe these orgies of excess. But there was something weird about this go around. I never wanted to cheat. At all.

Yes, I miss my drinks on Friday and Saturday nights, and alcohol will be coming back into my diet, though in moderate moderation. But do I miss sugars, grains, or dairy? Not really. Not enough to want them back, even in small quantities or in “moderation.” So, I won’t be rushing back to add cream in my coffee, I won’t be adding daily indulgences of dark chocolate, I don’t want my morning oatmeal… and those were the three main indulgences that separated my primal eating habits from the 100% paleo crowd. I don’t feel the need for beans at all. Maybe I miss corn chips… but no, I think not really. I guess I could see having a big cheat on the right Mexican or Italian meal.

And the thirty days went so fast… one blow-out carnivalesque cheat day per month now seems excessive to me. I think it’s enough to allow myself to have a higher carb day a few times a month (i.e. extra potatoes and fruit), primarily as a cyclic “re-feed” for training purposes.

I’d like to explain all these things in more detail but it’s 9:30, 8 hours before I have to get up, so it’s time for bed.

Bottom line is: you’ll see me out this Friday, at Highland Brewing Company, drinking a few beers, but that’s the only food with gluten I’ll plan to consume for quite a while. So, yeah, I’ll drink some liquor now and then. And one of these days I’ll blow it out with a big mexican meal and a pint (or two) of ice cream or a piece of peanut butter pie or an entire cheesecake. For old times sake.

But as I move on into day 32 of 100% paleo (tomorrow), I’m not really looking forward or back to non-paleo eating. Strict paleo is the new normal. It’s the new foundation.

Don’t misunderstand me. I don’t actually plan to stay at 100% paleo. To paraphrase Robb Wolf, I’m not making paleo into a religion here. The alcohol tells you that. I do in fact plan to allow a few, selected neolithic and processed foods and supplements — and these are or may be dairy based (primarily, I’m talking about protein supplements). I’m going to try cross-breeding the “leangains” approach to diet and supplementation with a paleo foundation and see what happens. That’ll be a new 30 day period. Starting… in a couple of weeks.

Stay tuned. Cause I’m always trying new stuff out.

Sincerely, yours truly, the N=1 experimental subject.

On Zone Blocks, and my Zone Prescription

Close readers of this blog know that I use Barry Sears’ “Zone” diet system as the foundation of my eating plan. And that, like many CrossFitters who are into the Zone, I eat a high-fat version of the diet. In this post I break down my thinking about how much I am eating, when I eat it, and why.

Revisiting “the Zone”

Explores my CrossFit inspired rediscovery of “the Zone” diet, 14 years after the original publication of Barry Sears’ 1995 book, Enter the Zone. In my own experience, the Zone-favorable diet is the best way to control your weight and promote your overall health and well-being.