by Barbara Berkeley, MD
For most people, the prospect of meeting a favorite movie star or sports hero would set the heart aflutter. Call me a nutrition geek, but I get palpitations from meeting the researchers and authors whose work on obesity I revere.
Several years ago, a friend from residency,who is now chief of endocrinology at a major academic center,invited me to meet Gary Taubes, the author of "Good Calories, Bad Calories". Taubes is a science writer with a long track record of producing sophisticated and meticulously researched articles for Science, the NY Times, and other highly respected publications. In recent years, he had become especially interested in the science of obesity writing a number of controversial articles that supported carbohydrate restriction and called into question the conventional wisdom of low-fat eating. "Good Calories, Bad Calories" was the a book that collected all the research that supported his contention (and mine) that the idea of controlling weight by eating less than you burn is insanely simplistic and that it is insulin-stimulating foods that cause weight gain and illness. A dense, lengthy book (the paperback version is 640 pages), GCBC defeated many readers. For me though, every page was a "eureka" moment packed full of research that supported everything I had learned clinically in more than 20 years of working with overweight patients. It became my bible, my favorite book, my go-to reference: the book that had my back. The pages of my copy were so underlined, annotated and studded with stars, arrows and exclamation points as to be barely readable.
The day that I was to travel to the east coast to meet Gary Taubes dawned to reveal an old-fashioned Cleveland blizzard. I was booked to fly on a small regional jet and believe me, I'm a nervous flyer. Normally, I would have taken one look out the window at the wind and snow and cancelled my flight. Instead, I tucked my trusty GCBC under my arm, packed an overnight bag and headed across icy, unplowed roads to the airport. I sat on the tarmac as our tiny plane (one of those that bounces and creaks across the runway) was doused with pink and green de-icing fluid. Moments later, the snow was reaccumulating on the windows and the wings were bouncing in the wind. Was I nuts? This was definitely a form of temporary insanity. But moments later, we ascended shakily into the sky, broke through the clouds and continued on to Philadelphia where a cold sun was shining.
At the university, I greeted my old friend and he ushered me into a large lecture hall where Taubes had just begun what was to be a long and detailed talk. The assembled crowd was composed of serious academic researchers in the field of diabetes and obesity. They listened politely and asked many questions, but seemed skeptical. Taubes answered each question with a wealth of data and a great deal of patience. It was clear that he was used to speaking to doctors and other scientists, most of whom had spent the past twenty to thirty years believing that dietary fat was the great villain. I understood his position well. My practical experience with obese patients was often ignored by peers who listened politely to what I had to say but went on to advise their patients that they eat "moderately",follow a "low fat diet" and eat lots of "healthy carbs".
After the lecture, I had the great opportunity of spending an hour or so in discussion with my friend and Gary Taubes. Naturally, I had him sign my copy of GCBC. The inscription reads: "This is the most annotated copy of my book I've ever seen." Later, we all had dinner with other members of the department. Gary and I avoided carbs while the others ate the rolls, ordered potatoes and (in some cases) fretted about their inability to lose weight.
In the years since the publication of Good Calories, Bad Calories, I have recommended it to many people but few have been able to wade through it and pretty much no one has enjoyed it with the blind excitement that I have. Apparently, this was a common scenario and now Taubes has produced a scaled down version of his master work called "Why We Get Fat and What to Do About It" (Knopf). While it (intentionally) lacks the intensive attention to research that characterizes GCBC, it does an excellent job of giving readers the basics. I recommend it. And if you are intrigued by what you read, I would suggest going on to GCBC to fill in the blanks.
The bottom line? It is the overproduction of the hormone insulin that makes us fat. This overproduction comes from two sources: eating too many foods that require insulin for processing (the starches and sugars), and the overproduction of insulin that results from body cells that become "resistant" through aging or eating too many S Foods. Dietary fat and protein do not stimulate insulin. Consumed alone they cannot make us fat. Most importantly, insulin prevents us from using the fat in our fat cells as fuel. We are thus always running on sugar. We crave more when we run out and we never get into fat burning mode. We are built to run on the fat in our fat cells as a major fuel. Most of us can't use it.
This knowledge is the currency of my world. It is obvious to those of us who "do" weight loss as a career. It has even---finally---become obvious to entrenched diet programs like Weight Watchers, who recently revamped its point system to reflect the fact that all calories are not alike. Some make you fat. Others don't.
For those with limited patience or someone who can only borrow "Why We Get Fat" for a day, I particularly recommend the second section of the book called "Adiposity 101". These facts are well presented and give you a good introduction to the problems created by insulin. (A similar discussion can also be found in the third chapter of Refuse to Regain on Metabolic Syndrome).
One of the points that Taubes makes repeatedly is that nutritionists and doctors remain entrenched regarding their thinking about weight loss. They insist that you can lose weight by eating less and exercising more when this formula has been an ineffective proposition for 95% of those who try. It simply doesn't hold up long term. He acknowledges that obesity doctors understand his thesis and support it and that docs who don't treat obesity are unwilling to listen to those who do. That's true. But it is also true that those who write about and research obesity, but don't treat it, are not privy to the daily observations of this knowledge in practice. So let me add some brief critiques of what is otherwise an excellent book.
1. Genetically Consistent vs. High Fat, Low Carb
Taubes touches briefly on the wisdom of eating foods that are like the foods eaten by our ancient ancestors. Theoretically, these are the foods to which we are best adapted. Following that, however, he pins the blame for obesity on carbohydrates and exonerates fat and protein. I agree unequivocally with his blame placing, however I remain very circumspect about the sources of our fat and protein. Taubes is fond of bacon and steak. I wouldn't have a problem with this if it were not for the fact that the meat we produce today is very nutritionally distinct from the meat we've always "known" how to eat. Bacon contains carcinogenic nitrites and other preservatives. Corn fed beef has a reversed profile of omega 6 to omega 3 fatty acids when compared to the meat of animals that graze. If we hypothesize that we get sick from eating a diet full of carbs because we are not genetically prepared to eat large amounts of carbs, how can we ignore the fact that eating meat that is very modern in composition may be equally damaging? The way I see it, logic leads me to believe that we get both fat and sick when we eat fuels that our body is not prepared to process genetically. Trying to get as close as possible to original food sources makes the most sense. There is no research on this by the way other than voluminous observation of hunter gatherer tribes that survived into modernity and were absent modern diseases.
2. How to Lose Weight
Many of the sources consulted by Taubes in this book suggest an Atkins-style diet for weight loss. There are also many obesity clinics that still use something called the "Protein-Sparing Modified Fast". This is essentially an extreme Atikins diet that has patients eat small amounts of mostly chicken, eggs and certain cheeses. While these diets do cause weight loss, they also can lead to complications of dehydration, dizziness and potassium and salt depletion. We have found them to be completely unneccessary and I can't understand why people persist in using them. Our diet has many more grams of carbohydrate than Atkins or the PSMF. Our patients eat one piece of fruit and alot of vegetables and salad each day. It works beautifully and we achieve large weight losses. We have rarely had a patient who is resistant. In other words, it is very possible to lower insulin levels enough to get brisk weight loss without going to total carb elimination. You just have to know which carbs to avoid and how much to include.
3. Calorie Lowering for Weight Loss
One of Taubes' interests is establishing a study that would document that fact that people on the Atkins diet could eat enormous numbers of calories yet still lose weight. This would prove that weight loss isn't about the amount of calories at all, but is about how the body uses the calories it gets. In other words, does it burn up the calories and get rid of them or does it store them? In the practical world of the weight loss clinic, however, we have found that to get weight loss, patients need to get calories low. Having tried the Atkins diet myself many times, I found that my calories were automatically limited by the boring nature of eating only meat and cheese. I don't know if Taubes is right about his belief, but it seems beside the point. Eating huge amounts of fat and protein doesn't feel good to many people, and weight loss can easily be gotten on a low insulin diet of about 1200-1400 calories that suppresses appetite as a side benefit.
Taubes makes the very interesting point that obese people are sedentary not because they are lazy, but because their energy stores are locked up (insulin traps fat energy and makes it inaccessible). They simply don't have enough energy to exercise and therefore don't want to. I agree with this. Our patients who lose weight become much more interested in moving. You only need to read a few weight loss blogs to see how frequently obese, sedentary people turn into avid exercisers, even marathoners. Taubes discounts exercise as an important factor in weight loss. So do I. However, I still stick to my guns when stating that exercise is crucial for weight maintenance. I don't know the technicalities of why it works, but we can suppose that it keeps the muscles efficient in their use of calories and allows for the whole bodily machine to run better. Exercise is like the oil or lubricant for our metabolic system. Keep it going.
I highly recommend that you take a look at "Why We Get Fat" and see if it doesn't get you thinking. I hope you will come out believing that restructuring your diet to permanently rid yourself of the bulk of your grains and carbs is the true solution for permanent weight control. It has worked for me and it has worked for all of those I've been able to convert.