November 20, 2008

Sears' Toxic Fat: The Man, the Diet, the Controversy

Who is Dr. Sears?

Okay, pop quiz time.

Two out of the following three statements apply to Barry Sears:

1 - He's got a Ph.D in biochemistry.
2 - He's the author of The Zone Diet.
3 - He's the star of a movie that just came out about teenage vampires who sparkle and have a lot of biochemistry.

Warning: if you flunked that quiz, you might be reading the wrong blog.

Barry Sears exemplifies the important role the preposition plays in the English language. People who've read his books either swear by him, or swear at him.

Unless you've been living in a chemically sterilized biosphere for the last 13 years and had earplugs on the whole time you were there, you've probably heard of Dr. Sears' book "The Zone Diet." He has a new book out, called Toxic Fat.

Seeing the word 'toxic' in a title makes me suspicious, simply because a lot of marketing folks have jumped on the bandwagon with this particular word. I know marketing sells books; I still object to it if the words they use have the effect of making the book's actual message unclear or inaccurate. I got so fed up with marketing claims that I wrote an overview of the biology behind the term 'Toxic Fat'.

In this case, I'm not sure if I agree with Dr. Sears' claim about fat itself being toxic. Which is a shame, because there are good points in this book.

Toxic Fat briefly mentions fat cells storing toxins, but that is not the main focus of the book. Not toxins from pollution, at any rate. What this book focuses on is the toxic effect of the 'bad' fatty acid Arachidonic acid (which I abbreviate ArA 'cause there's no way I'm typing that out over and over again).

You may not have heard of ArA, but you've heard of its rivals, the fatty acids that lead to Omega-3 fatty acids being produced in the body.

I've found this book difficult to review for two reasons. One, there's a lot of information in it, and it's hard to condense. I wrote a lengthy, detailed, highly erudite analysis -- you can thank me later for not posting it.

The other thing that made this book difficult to read, for me, was the fact that Dr. Sears' books are considered controversial, so I felt constrained to stop and analyze every sentence.

What is Sears' approach to Toxic Fat?

This is where it gets complicated. I also wrote a long, detailed description of the biochemical processes involved in the production of Omega-3 (good) and Prostaglandins (bad). You can thank me for not including it here.

Instead, here's the short version:

Alpha-linolenic acid is one of the omega-3 fatty acids. (Couldn't fit them all into the diagram.) Prostaglandins are bad. Prostaglandins are responsible for painful menstrual cramps. I do not like them.

I'm simplifying horribly but the main contentions are:

1 - Uncontrolled inflammation screws up the body.
2 - Diabetes, heart disease, obesity are all caused by inflammation.
3 - Arachidonic acid (ArA) plays a large part in the inflammation epidemic.
4 - According to Sears, the Zone Diet is the answer to this problem.

Dr. Sears vs. Cranky Fitness

Uncontrolled inflammation is on the rise
Sears Yes
Cranky Fitness Yes

High levels of ArA lead to high levels of inflammation
Sears Yes
Cranky Fitness Yes

Uncontrolled inflammation leads to heart disease, diabetes, obesity
Sears Yes
Cranky Fitness Yes*

The Zone Diet is the way to alleviate inflammation
Sears Yes
Cranky Fitness Read More

*I hesitated over his claim that inflammation is linked to obesity; a person can be 'fit but fat.' If he means (and he probably does) someone with a lot of abdominal fat has problems with inflammation, then yes.

It is really dangerous when you get so much fat in the abdominal area that the body starts storing fat in the liver. A fatty liver can kill you just as nastily as a liver soaked in vodka.

What's so controversial about Dr. Sears?

Sears' books are controversial because at the heart of all his books is the Zone Diet, and many nutritionists and doctors, such as Joel Fuhrman (Toxic Hunger), disagree stridently with Sears' conclusions.

When is a diet like a restroom?

There are lots of sites that explain the Zone Diet in detail. (The 20-second condensed version: you should eat fats, proteins, and carbohydrates in a precise ratio suited to your size.) In the Toxic Fat book, meal plans are separated by gender -- different ones for men and for women. (Essentially, men have larger portions.) Except that not all woman are small, and not all men are large, so I'm not sure if that works. Maybe he's basing this on the fact that men have more muscle mass?

I can't whole-heartedly endorse this diet, but I can't condemn it either, not 100%. I mean, anything that gets people to pay attention to what they eat, and that helps them lose weight, isn't all bad. (I just know someone will write in to say that this diet has helped them, and who am I to say that's a bad thing?) I will say that I don't think it's a long-term diet and I don't think long term it's healthy and sustainable.

My problems with the Zone diet are based on anthropology and psychology as much as biology. I don't see that the human body was designed/has evolved to a diet that is so precisely balanced.

The other problem is that there is no way that I could follow this diet. I know myself well enough to say that without someone else doing all the weighing and calculating, I'd give up the Zone diet in a day. All that math would drive me crazy. (I know people say "oh, it gets easier... you get used to it..." but in my case I doubt it. I had enough trouble trying to eat 4 or 5 servings of vegetables per day. Much much simpler to go all vegetarian with the occasional night out.)

Toxic Fat: The book

Good: There's a long bibliography listing his sources for the claims made in each chapter.
Bad: Many of the sources cited are from his previous books, which seems a kind of circular logic.
Ugly: The polysyllabic names of the many different fatty acids under discussion. It's like one of those Russian novels where all the characters have names that are twenty syllables long.

One thing about his diet argument that I can't agree with is the seeming contradiction between his claim that ArA is bad (which I agree with, or at least I agree that it's bad in high levels), and his insistence on eating lots of meat-based protein. Sears claims that the high-level of ArA in the typical diet is due to the cheap vegetable oil that is so readily available these days. I don't see that he proves this point. Other sources (here's one of them) claim that the major sources of ArA are meat, poultry, and eggs.

Instead of making sure your diet is a certain percentage of meat, I think it is more helpful to make sure your diet is 100% organic, and as Dr. Weil would say avoid food that has a long list of ingredients you can't pronounce. Avoid food with added hormones, antibiotics, or a long list of unpronounceable chemical preservatives.

To sum up, this book makes some good points as well as some not so good points (points that I don't agree with, I lump into the 'not so good' category automatically). I don't agree that the diet he suggests will help, but I completely agree with Sears' claim that we need to pay attention to inflammation and the dangers it presents.

Other reviews you might like

Diet Blog
Pasta Queen (Half of Me)

Has any one else read this book? Or tried the Zone Diet? If so, what did you think about it? I'd love to hear other people's viewpoint on this issue.


  1. I grew tired a long time ago of people who claim that their way is the best way no matter what no arguments allowed. A person should always be open to the possibility that he/she is wrong.

    Since all people are different, obviously the diet that works for one might flop with another.

    You are correct in that paying attention to what you eat is the key, not rigidly pushing everyone to do it your way or hit the highway.


    1. If you have a problem with people like that then you should be on the side of Dr. Sears. He's continuously modified the details of his dietary theories as new information has come to light. The basic principles haven't changed but those basic principles are just a matter of moderation and consistency.

    2. If you're tired of people like that then you should be on the side of Dr. Sears here. He's continuously modified his dietary theories as new information has come to light and that's the mark of a true scientist. His basic principles haven't changed much but that's because they are based on moderation, consistency and actual biochemistry, which regardless of how "people are different" ... don't change.

  2. I think there is something to be said about the zone diet and toxic fat. I want to get the book. Dr. Oz talks a lot about inflammation in his book and I love his down to earth view of things.

    My sis did the diet years ago and lost a lot! Yes, she gained it back but she did lose and stick with it for about a year.

  3. First of all, Ugh. I think I'm the only person on the planet who hated that book.

    Anyway, I agree with you regarding how it is probably just easier to eat organic food and stay away from the processed stuff. That alone should make a huge difference in your health without having to follow a complicated diet plan that would be difficult to sustain long term.

    I actually posted something today that mentioned that blueberries are an anti-inflammatory. I didn't know that and thought it was interesting.

  4. I haven't heard of it. Or him. I read part of the Zone Diet, but it seemed like a bunch of other diets.

    I'm not sure I'll be buying or reading this, but thank you for reviewing it: It seems like something that would pique my interest.

    1. If the Zone diet seemed to you like "a bunch of other diets", you didn't read it very carefully.

  5. I want to read this book! Does he preach the evils of trans-fat or just ArA.

    Cranky I agree with you that ArA is coming more from animal fats than cheap vegetable oils.

    Always interesting to hear different authors in the nutrition industry battle about good fats vs. bad fats -

    1. Trans-fats are the easiest way to shut down healthy fat metabolism and Sears has preached the evils of them since day one. ArA is much like cholesterol, influenced less by consumption and more by how that content is processed. This is what Sears' dietary strategies are about, controlling hormonal expression with diet so that consumed fats are metabolized in as healthy manner as possible.

  6. Actually, I've never read the vampire book. Sounds like I shouldn't bother?

  7. Diet books make me crazy. It's an established fact. So, despite teh fact that I have a deep yearning now to read this book I will restrain myself and not. That said, your review was hilarious and interesting. Loved it!

  8. I saw dr sears speak in person back in the DAY (1994?) when he wasnt trying to sell books (IMO) and was just a dr trying to help people.

    the zone was newly released and mainly targeting other physicians.

    he is mindblowingly smart and articulate.

    for that reason alone Im gonna check this out!

    1. Anyone who truly believes in what they do, eventually has to make a profit doing it. Otherwise, you severely limit the amount of time and energy you can afford to expend on the thing you believe in so strongly. This is fairly undeniable.

  9. I'm not sure how to condense this, so excuse me while I purge my feeling about this all over your comments.

    I've really been interested in management/avoidance of Diabetes for years due to its overwhelming presence in my family. I have to say that while I don't follow the Zone diet per se any longer (I felt that proportions were too rigid for me to follow all the time)- Much of what Dr. Sears says makes sense to me.

    I like the idea of making sure I get the components of a healthy diet: quality protein, healthy fats, complex carbohydrates, and produce. I find that I have a tendency, no matter how healthy I'm eating, towards inflammation and I do find that when I'm more conscious to avoid foods that trigger an inflammatory response in my own body I feel better and look better. Does it mean that I can avoid or delay the onset of Diabetes by eating this way? I don't know. But trying something is better than doing nothing.

    When I was pregnant with my third child I developed Gestational Diabetes. My nutritionist laid out a plan of what/how to eat that I followed (it followed the idea that a carb is a carb; and any carb will act the same way in your body). I felt differently and really ate in a way that was more "Zone" in practice. I measured my blood sugar an hour after every meal and upon waking. The two times I had a blood sugar reading over the acceptable number was when I had a very small amount of refined carbohydrates. It may be true that in most people, a carb is a carb - but for some who are more insulin resistant, I think that we really have to be careful of what food we eat, not just how many calories we consume.

    If I had followed my nutritionist's advice, I definitely would have been put on insulin therapy. I have Dr. Sears to thank for the fact that his ideas helped me to avoid that.

    1. Starch carbs are definitely different than those with nutrients and fiber, vegetables and fruits. This should be obvious. Whole grains ground into flour will turn them into more of a starch carb, which causes inflammation and weight gain. I've tried it over and over. this seems to be true of the bad carbs vs good carbs.

  10. I agree that you can't dismiss any diets that others swear by.

    For some it may just be a matter of common sense. Eat things that are good for you in moderation, cut out processed foods. Others require drastic alteration of their consumption habits in order to live a healthier life.

    Great review. I'll have to check this book out!

  11. Wow!

    Just poking my head back into blogland after a long stretch of no web, and what a helpful review! I love the awesome graphic summary--you just saved me hours and hours of time and the cost of the book.

    Had I made my way through the book (and not been away loafing on a road trip), I think I would have come to the exact same conclusions--"yes" on the statement of the problems, but "no" on the particular dietary solution proposed.

    Thank you for your excellent review! And for sparing me all those polysyllabic fats.

    (And I'll just throw in a massive apology to all whom I owe emails to--will be back early next week and rarin' to go!)

  12. I've followed The Zone very loosely for a while now. I just switched over to following the Paleo Diet, but thats another story.

    I actually do agree with Sears' theory of meat based proteins. But there is a huge carve out in that he doesn't really talk about the effects of industrial agriculture on the ArA in meat now. Grass-fed beef is totally different nutritionally than corn-fed beef. Tho I haven't read Toxic Fat yet, he may not be making that claim very well. Michael Pollan's "Omnivore's Dilemma" does a far better job of establishing that.

    Great post, Merry.

    1. Sears also wrote an entire book on soy based protein.

  13. What a torrid title for a diet book. And the subtitle is even worse (better?): "When good fat turns bad."

    I'd almost half-expect this to be some kind of pulp fiction involving a naive librarian being lured to "the dark side."

  14. Interesting review of it! Diets just make me wary all around.

    I pretty much agree with your thoughts on these things... there's no one size fits all and also that kind of math would drive me nuts. Math is the devil.

  15. Wow - another diet book, another buzz word used to promote another... "diet" book! But I want to thank you for the frank reading and for your well-researched (and explained)review. I have gone on the Zone diet a couple of times with little success and no lasting success at all. But I'm very open these days to listening to discussions about controlling "inflammation" overall - whether applicable to fat, heart disease (arteries or other organs) or the thumb I knifed chopping veggies a week ago. Thank you tons for bringing this book to my attention!

  16. Lately I've been feeling that the more I pay attention to all the dieting and foods and stuff that when I eat it causes me to have the reaction of feeling guilty because I ate it, is making me fatter than if I just ate like a normal person.

    Is there a diet book for normal people?

    Inflammation supposedly causes cancer too but that might be why they say that obesity is a huge (no pun intended) risk factor for cancers.

    1. If you're looking for a diet book for "normal" people, "The Zone" is it.

  17. Hey! If you combine the book 'Twilight' with the book 'The Zone Diet', you get 'The Twilight Zone Diet'!

    hee hee hee

    Yes... I am easily amused...

  18. POD
    I threw out a large section of the review dealing with obesity, inflammation, and cancer, but I agree there might be a connection.

  19. My father was on a loose zone diet for a while. Actually, he did Atkins, but I remember he ate Zone bars. He has gained some of the weight back, but I'm not really sure how strict he is on the diet.

    Great review, Crabby, thanks!

  20. I find that I have a tough time following a diet with lots of rules. Also, I get a little confused when one diet book comes out and contradicts another I just! I agree with POD, just want a diet book for normal people!!

  21. WOW. What a good post. We do book reviews, but I'm not touching that one with a 10-foot pole. Please, I think you summarized it quite perfectly. :)

  22. Ooh, you made charts! Trying to show me up, eh? :)

  23. First, I have to say that I actually DID lose weight on the Zone diet, and I felt pretty damn good, too. Because you eat so. many. freakin'. vegetables. at every meal, I was never hungry, either, even on 1200 calories a day, which was a first for me.

    Second, I agree with JC about the difference between "conventionally" produced meat and grass-fed, free-range, hormone- and antibiotic-free meat. The former is bad for me. The second? Not at all. (IMO, and YMMV.)

    The BIG downside to the Zone? The numbers. The counting, oh GOD, the counting. There is actually an easier way to do it, based on portion sizes on your plate: 1/3 for meat, 2/3 for veggies - something like that. I counted, because I was WAY to obssessive to just guess based on portion sizes, but if I'd done the sizes, I might have stuck with it a lot longer. (I'm actually thinking about going back to it using the portion sizes instead of the counting.)

    For whatever all that's worth. :)

  24. Merry,

    The Twilight Zone Diet sounds perfect. I think that's the diet I've been on for the past 50 years - since birth or soon there after.

    When will you post the review part of cancer and inflammation and obesity? I won't take it personally.

  25. For me, even the Zone diet is too carb heavy for me. My intake of carbs have to be as low as possible. I do eat as much carbs from veggies and some fruits in though. I do know others that this diet has worked for.

  26. With all the woes attached to meat consumption... one would think eating veggies and fruits would be the panacea. Personally, aside from my love affair with chocolate and some candy bars (I know I know...) I think the best is to stick to foods that are as close to their natural state as possible. Go for organic meat whenever possible.

  27. Ages ago, I tried the Zone diet for part of a week. It really was too much calculating-intensive for me to keep it up.

  28. Great book review, thank you. I personally can't get past the first few chapters of any weight loss book!

  29. I haven't read anything by Barry Sears nor do I plan to. I have read quite a bit about Omega 3 fatty acids though and the new Sears book is based on some old news. Because many of us eat produced food or grain fed animals we tend to have diets that have far too much Omega 6 fatty acid (also essential) in our systems. It is the ratio of omega 6's to omega 3's that matters. This ratio imbalance throws our cell walls out of whack (yes, the highly scientific explanation) and ties into some of the chronic inflammation problems people have (heart disease is one example). Anyway the shortened diagram has some truth tied to it. And there is real research to back it. Just look around and read something other than a trendy diet book that makes all kinds of promises.

    I liked Michael Pollan's last book _In Defense of Food_. He doesn't outline peer reviewed research but discusses the implications of industrial food. It's a good general resource to get you thinking about some of the things that are set in motion by our food system. Don't waste your time on a diet book...instead find out where your food is coming from and what it is doing to your body. It will blow you away.

  30. Anon, I wish you'd included your name so I could thank you personally for the great comment.
    If I had to choose between reading a book by Sears or /anything/ written by Michael Pollan, I'd choose Pollan. No competition.

  31. Whether it's Atkins, Protein Power, South Beach, or the Zone, the fundamental key result is maintaining the lowest optimum level of insulin and glucose. Both are inflammatory and are key players in the metabolic syndrome. If you wish to gain some insight into the effect of diet on disease read the "Lap-Band diet" It is the diet to be followed after the bands are placed around the stomach. In about 75% percent of the Lap-Band patients need for diabetic or cholesterol meds is suppposedly eliminated. You can be sure it's not the bands, its the diet they are now are forced to follow. Compare the Lap-Band diet to those mentioned above. Any one of them is a "piece of cake" (sorry about that) compared to the Lap-Band or any other post bariatric surgery diet.

    Do some research and see how the Joslin Diabetes Clinic (Harvard) modified it's diet for obese diabetics in 2005. One might suspect that someone at Joslin had a copy of the Zone (or Proten Power, South Beach, or Atkins), read it and used what they liked.

    Enough of the pickey stuff. Follow the diet that will reduce your insulin and glucose (of course you know what that will be), take enough fish oil to get at least 1500 mg/day of combined EPA and DHA, and take enough vitamin D-3 to get your blood level of 25(OH)D up to at least 100 nmol/L (periodic blood tests necessary-if you live up north you may be taking 2000-4000 IU per day).

    Warning: following this advice will harm your doctor's income.


  32. oh i love your blog. you know i think Sears has bit of a point. i was/am a veggi but not a good one. i loved junk food eating out a lot (where most of the oil restaurants use is soy bean oil or cheap veggi oil... and soy beans have been linked to suppressing thyroid function). got fat. put on a lot of belly fat, and never cooked a meal nor made too many salads. courted inflammation in ignorance. after a long journey through auto-immune, i am coming back to a sane life as a raw veggie (80/20). and i stick to only olive oil, coconut oil, palm oil (and refrigerated flax oil in raw dishes)... a world of difference. hope he says something about liver cleansing. it is the other key in preventing degenerative diseases. (you know how many people like me who mostly eat out and eat junk and are not veggies have had their gallbladder removed? nearly half of the people i work with. wow!) he might not have the story, exactly right, but their is a definite oil and degenerative disease link. thanks for the post and a most informative blog!

  33. This comment has been removed by the author.

  34. The Zone plan might not be for everyone, but there is one diet essential that Barry Sears underscores as being beneficial to everyone: fish oil. He gives lots of info to back up the fact that it's effective at preventing and reducing inflammation. That alone seems worthy of our attention!

  35. I am following the ideas of the Zone and KISS (keeping it simple stupid), using the plate method of a palm sized piece of protein (tofu, beans etc. are encouraged along with lean meats so not all meat), then double veggies and fruit and a small amount of fat, usually in the way of olives or nuts) I don't weigh a thing. I refuse to be anal about it as that is what got me fat in the first place.

    The diet can be as easy or complicated as you want. It all depends on how you approach it.

    I have found it really helps in the ways of my knees and asthma which I suspect is linked to wheat and inflammation. I can even eat his bars which are very yummy and not have an asthma flare up like I would with anything other sort of bar, treat or bread product.

    So far so good. I have been doing it for almost a month and find it not difficult.


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