The main CrossFit website provides simple recommendations for diet: eat 30% protein, 40% carbs, and 30% fat, while avoiding as much as possible all processed foods, simple sugars, and starches, and emphasizing fresh fruits and vegetables. CrossFitters also make repeated references to the “Paleo-diet” approach.
Dr. Barry Sears
I recognized all of these dietary prescriptions right away, because they are actually rooted in the work of Dr. Barry Sears, whose “Zone” diet exploded onto the health and nutrition scene in the mid 1990’s. Back then, I actually read two of Sears’ books, and while more or less following a “Zone” diet in 1996 to 1997, I lost about 40 pounds (I went from 215 to 175 lbs)!
In 1998, I was in the best shape of my life. But then I met my wife, who is a slight and athletic former dancer who has never had a weight problem. Over the years, I have let every bad eating habit back into my life, starting with gobs of pasta, and progressing to frequent desserts. I also abandoned every favorable eating habit I had developed when I was following the Zone diet (like eating 5 meals a day). All this was done for the sake of convenience, and for work, and family, etc., and also for the pure love of food. Anyone can tell you I am crazy for all foods.
Shortly after Sears became mildly famous for his “Zone diet,” there was a major commercial and popular revival of the Adkins “diet revolution” (first published, I believe, in 1972). Adkins’ revolution shared in common with Sears’ diet an emphasis on eating protein and a criticism of carbs. But the Adkins diet really severely limits carbs, and lets dieters eat as much red meat and cholesterol and saturated fat laden foods as they like. This approach doesn’t make a lot of sense given what we know about bad fats and the benefits of good carbs, so Adkins’ diet gave “high protein diets” like Sears’ a bad name. The result was, people tended to forget about Sears’ moderate plan. Instead, they ridiculed Adkins. Ultimately, it seems like everybody went back to their plates of pasta and expandable pants. And I went along with them. For the last few years there have been no rules to govern my diet, and my health and waistline have suffered as a result. So I had a great motivation to re-read Sears.
Wanting to renew my knowledge of the “science” behind the idea of eating a “Zone favorable” diet, I decided to re-read my copy of Sears’ best-selling 1995 book, Enter the Zone, which first introduced his ideas to the public. It’s been collecting dust on my shelves for 10 years.
It must be admitted that the book is not a great read. It has the same problem which is shared by so many popular self-help treatises: it incessantly repeats its main ideas over and over. Sears’ main idea is not just the spine of this book: it is the skin and muscles too. We encounter his main ideas at the beginning, middle, and end of each of its sixteen chapters. The main idea is repeated both to the exclusion of scientific detail and to the exclusion of more practical advice. This is a major weakness.
Also like other popular works that purport to represent the results of scientific research, the book is deeply flawed because of its tendency to gloss over details and over simplify complex issues until their truth is drawn into question. The book lacks footnotes or endnotes, and has no bibliography. Citations to research studies are not given in a form which would allow the educated or dedicated reader to learn more. And while Sears should be commended for occasionally writing like a scientist — he almost always clearly distinguishes between which of his claims are based on verifiable scientific research, which are based on anecdote, and which are based on inference and conjecture — it’s still just not scientific enough. He could have provided a more clearly organized and readable text, with properly scientific endnotes and bibliography, that could then serve as a reference and starting point for further research and study.
Never mind these criticisms, I have more important things to say about “the Zone.”
First, you need to understand Sears’s most basic ideas, which are as follows:
- your body composition (i.e. percent of lean and fat mass) is primarily the result of the balance of hormones in your body (especially insulin and glucagon, but also the important hormonal precursors called “eicosanoids”).
- your overall health, susceptibility to a wide range of illnesses and diseases, and your ability to heal is also largely the result of your hormonal balance.
- the most important factor controlling your hormonal balance is your diet. The macronutrients and micronutrients found in your diet affect your hormones directly, and you can control the hormonal balance of your body through controlling your diet. In fact, food should be understood as a drug.
- the right balance of the hormones insulin and glucagon can be maintained if you maintain the right ratio of the macronutrients protein and carbohydrate in your food.
- This right balance of hormones and eicosanoids is called “the Zone.” (Hey, this fact is important: the diet is not called the “the Zone,” the hormonal balance it helps you reach is called “the Zone.” The diet is called “the Zone favorable” diet because it lets you get into the Zone.
- every time you eat, at every single meal, you should strive to maintain a ratio of 3 protein units to 4 carb units. But any raito of protein to carbs that falls somewhere between 6 to 10 (0.6) and 1 to 1 (1.0) may work for you.
- your total caloric needs should be based on your body’s total protein needs (between .5 and 1 gram per pound of lean body mass, per day).
- your should probably derive 30% of your calories from protein, 40% from carbs, and 30% from fat. However, athletes can eat more fat.
Believe it or not, that is it. The rest is all rhetoric and review of some of the scientific evidence which supports his often wild claims for how much more healthy humans could be if they would adopt this approach to their diets.
Here’s what Sears says living in the Zone can do: it can improve athletic performance, help you lose weight, control pain and inflammation, improve cardiovascular health, prevent heart attacks and strokes, prevent or possibly even cure cancer, prevent and/or reduce symptoms or even cure a large number of autoimmune diseases (from AIDS to arthritis), treat skin disorders and psychological problems, and possibly help you you extend your life to nearer your biologically maximum age of around 115 years.
What many people don’t understand about this “Zone-favorable” diet system that Sears advocates (the 30/40/30 diet), is that it is a calorie restricted diet. It’s a low calorie diet.
The amount of protein that you eat is rooted in what should be a pretty stable number for most people: daily protein requirement. Our bodies need only limited quantities of protein. Although many people don’t get enough quality protein in their diet, we actually don’t need all that much.
To make this diet work, you first determine your daily protein requirements and then base your diet off of that. My needs, for example, are calculated like this: because I weigh 205 lbs, but my lean mass is only around 161 lbs, I only need between 82.5 and 165 grams of protein per day, depending on my activity level. I am very active, participating in heavy weight lifting and fast metabolic conditioning exercise at least 4 times a week, so I would estimate I need between 120 and 160 grams per day. If I make 160 grams of protein just 30% of my total calorie intake, then my total calories per day will be a mere 2,133 calories per day. For a large active man, that is a low calorie diet. A less active person at my weight and lean mass might eat as few as 1100 calories per day! (If I need more calories because I do a 5 mile run or something, then I add fat to my diet).
Because the plan involves eating so few calories, if a regular person (who was formerly eating like crap) begins to follow this low-cal diet plan, he or she will lose weight. That can be guaranteed, because most people eat a lot more than 1100 to 2100 calories per day. They typically eat double that amount.
When we eat fewer calories than we burn, we lose weight. So, the fact that people usually lose weight when following Sears’ diet is not surprising. In fact, if you want to lose 10 pounds in a month, I am certain you can do it on Sears’ diet quite easily (assuming you can figure out how to actually measure and weigh and count the macronutrient contents of your food correctly).
But that’s not really the issue, is it? Sears claims that his special system of balancing hormones by maintaining a 3/4 protein to carbs ratio will cause your body to change dramatically and hormonally. He claims you’ll feel “in the Zone” … filled with energy, health, vitality, and other benefits. He claims your weight loss will be fat loss, and that your metabolism will adjust itself so that your body starts to run off of all of those stored fat calories. And truly optimum health will follow.
The only way to determine whether these claims are worth anything would be to test the theory by doing it one’s self. Or to wait for science to verify the claims. Now it’s been 14 years since his book was published, but I haven’t heard of any large scale scientific studies which have investigated his hormonal claims thoroughly and with a large number of participants. That’s probably because diet and exercise studies are hard to run, harder to control, and even harder to fund. (No drug company money!)
Maybe that’s why Sears’ magic tree-of-life / fountain-of-youth diet plan remains largely unappreciated or unknown, or subject to so much skepticism.
As for me, I was hoping the book would provide me with some really practical strategies for actually putting the diet into practice. Cause I am going to try it for a month. But I was disappointed. What I found was that Sears is not a very good dietician OR chef. He claims that one must practice this very precise balancing act with foods, and then provides only the most imprecise system for putting the act into practice, fudging and estimating macronutrient quantities in foods all over the place.
His recipes are awful. His recommendations for the use of certain foods don’t really take into account their true ingredients. As an example of this carelessness, he recommends on one page that we shouldn’t don’t eat egg yolks because, like fatty red meats, they contain lots of the deadly fatty acid arachidonic acid. But then a few pages later he recommends that you use mayonaisse to add fat to your diet—apparently unaware or unconcerned that one of the two principle ingredients of mayo is egg yolks.
Also, advocates of the “paleo-” style diet won’t love Sears’ book. Although he has an entire chapter (“Chapter Nine: Evolution and the Zone”) in which he shows himself to have been an early pioneer and advocate of the so-called “Caveman” or “Neanderthal” diet, his actual diet recommendations rely too much on products of the agricultural revolution: corn flour, wheat flour, oatmeal, cheese, milk, and other foods that a caveman would never have eaten. Modern “Paleo-Zone” devotees avoid these like the plague. Furthermore, in 1995, Sears was not a fan of nuts (I think because they have too much omega-6 fat, aka linoleic acid). Today, the Paelo-diet gurus practically consider nuts a food group of their own. (For the record, a look at Sears’ website shows he now recommends Peanuts as a source of fat).
All in all, Enter the Zone is a deeply flawed book. But like an ancient map to a buried treasure, in which not all the details are true to life, and in which the occasional mythical monster frolics in the waves near the compass points, Sears’ book might, just might, point the way to something of inestimable value. Let the explorer beware!
For Dr. Sears’ website: http://www.zonediet.com/