Book Review - "Why We Get Fat" - Gary Taubes

*One of the things I have committed to do this year is to read at least 20 books. I used to love to read, but after what was essentially seven straight years of college (finishing my Bachelors and then obtaining my Masters Degree), I was burned out on reading. Not a day went by during those seven years that I didn't have an assigned article or a textbook with me to read. Since completing my Thesis last March, I haven't done much reading other than what I have read on the Internet. So, I have some catching up to do, starting with the stack of books on my bookcase. I just finished my first book last week. It was so good, I wanted to share with you my thoughts about it.   

I'm not a Dietitian, I just play one on TV. 

I may not be a Doctor nor a Dietitian, but what I am is a person that has struggled with my weight for most of my adult life. In 2006 my weight had ballooned to 284 lbs. I was starting to experience the health issues associated with being over weight and it scared me. I wrote about my situation more extensively here, so I don't want to rehash the gory details in this post. As a reminder, over the course of 18 months, (from November 2006 to May of 2008) I lost 115 lbs. My weight went from 284 lbs to 169 lbs (before and after photos can be seen at the link above). It was such a personal blessing for me to lose that weight, and of course, I fully believe a life saving one as well. I have not been able to keep my weight at the lowest level I reached, but I am happy to report that I have not gained too much of the weight back. It seems strange to say this, but it has been much more difficult keeping the weight off, than it was to lose it in the first place.

Prior to my efforts in 2006 I had attempted several different ways to lose the weight. None of them worked very well. One "diet" I had tried previously, did give me good initial results, however, I did not stick with it. It was the Atkins low-carb plan. When it became clear to me in 2006 that I needed to do something, I decided to give Atkins another try, this time, i modifed it slightly to what worked for me AND I made a serious commitment to follow through.  This was really an attempt of last resorts, as my family was pushing me to get gastric bypass surgery and my doctor wanted me to try a pharmacological approach. I want to try neither. For me, it was an issue of self-respect. I needed to do it the "right way," as hard as it might be. The rest, as they say, is history.

Given my experience, I am fully convinced that a low-carb approach is the best weigh (pun intended) to lose weight.

While I had done a great deal of reading on the science behind the low-carb diet, it always tended to be very technical and slow going. Now, thanks to Gary Taubes, you can understand why low-carb diets work. In fact, "Why We Get Fat: And What To Do About It" is one of the best books I have read on the subject. I highly recommend the book.

Taubes is a Science writer. He has won the Science in Society Journalism Award of the National Association of Science Writers three times and was awarded an MIT Knight Science Journalism Fellowship. He is also a Robert Wood Johnson Foundation independent investigator in health policy.

Over the last 30 years or so, the conventional wisdom has developed that we get fat because we consume too many calories and expend too few. Sometimes referred to as the “energy balance” theory and more commonly known by the phrase "calories in/calories out." The implication of this theory is that if we could just control our impulses (or at least control our environment, and thereby removing temptation) and if we could just push ourselves to exercise more, we’d be fine. This makes the issue of obesity primarily a behavioral one.

Additionally, when addressing the consequences of obesity i.e. diabetes and heart disease, the focus of the medical establishment has been on fat calories and saturated fat in particular. Yet despite the concerted efforts of the federal Government and the Medical establishment to educate the citizenry on the dangers of fat, we are facing health and obesity epidemics. Five decades ago, one in every nine Americans were considered obese. Today, it's one in every three and two in three are considered overweight. Something is not working. Could it be that there's more to the problem of obesity than gluttony (i.e. over-eating or calories in) and sloth (i.e. lack of exercise or calories out)? Could it be that the focus on fat is all wrong as well?

Taubes says yes. In fact the book posits two main points in this regard. First, physiology drives over-eating and weight-gain rather than psychology or character. Second, dietary fat, whether saturated or not, is not a cause of obesity, heart disease, or any other chronic disease of civilization.

What then might be the cause? It's important to remember that calories are units of measurement to indicate the energy content of the food we eat. There are three main types of calories we can consume to gain energy. They are characterized by the nutrients we get from them: fat, protein or carbohydrates. The issue of obesity is not about the amount of calories we eat but rather about the way those calories impact the hormonal regulation of the metabolism. In particular, carbohydrates play a special role in the secretion of insulin in the metabolic process. According to the book, two factors determine how much fat we accumulate, both having to do with the secretion of the hormone insulin.

First, when insulin levels are elevated, we accumulate fat in our fat tissue; when these levels fall, we liberate fat from the fat tissues and burn it for fuel. This has been known since the early 1960s and has never been controversial. Second, our insulin levels are effectively determined by the carbohydrates we eat-not entirely, but for all intents and purposes. The more carbohydrates we eat, and the easier they are to digest and the sweeter they are, the more insulin we will ultimately secrete, meaning that the level of it in our bloodstream is greater and so is the fat we retain in our fat cells.

In other words, we do not get fat because we eat too much or don't exercise enough, "we get fat because the carbohydrates in our diet make us fat." Obesity is a hormonal (overly secreted insulin) issue, not primarily a calorie in/calorie out issue.  That's not to say that there are not lifestyle choices we need to make when it comes to staying lean and healthy, but those choices have to do with the types of carbohydrates we decide to eat or not eat.

Taubes divides the book into two parts. The first part of the book looks at the evidence for the calories in/calories out theory and why it comes up short, scientifically and otherwise. This section is really quite enlightening and thought provoking. In the second part of the book, Taubes looks at the science behind the idea that the growth of our fat tissue leading to obesity is "driven and controlled by hormones." He calls this section "Adiposity 101."

Adiposity is the quality or state of being fat. Taubes discusses three laws of Adiposity (his tweak of the medical establishment for relying on the laws of thermodynamics to explain the calories in/calories out hypothesis). The first law is that "Body fat is carefully regulated, if not exquisitely so." Everything else in our bodies is carefully regulated, so is the accumulation of fat. Just as when body system regulation breaks down (as in cancer for example) the results are obvious, so too when we accumulate excessive fat tissue it is a sign that the metabolic process has gone awry.

The second law of adiposity states: "Obesity can be caused by a regulatory defect so small that it would be undetectable by any technique yet invented." His point here is that in the context of the calories in/calories out theory, even a 20 calorie a day surplus in our energy balance can lead to obesity in the future. If we gain just one percent in our typical daily calorie quotient we will go from lean in our twenties to obese in our fifties. In the same way, it is easy to imagine how our fat regulatory system can get slightly off through the abuse of the secretion of insulin not because of how much we eat, but because of what we eat.

Taubes' third law of adiposity states that "Whatever makes us fatter and heavier will also make us overeat." In other words, we don't get fat because we overeat, we overeat because we are getting fatter. Here Taubes makes the point that it is only natural that as the body grows, it needs more and more fuel. Have you ever been around a growing teenager? They eat, and eat, and eat. Why, because their body needs the food to satisfy the demands of growth. This is true when we are obese as well. It may seem counter intuitive, but over-eating is an effect of adiposity, not necessarily the cause.

When people who are obese try to restrict the amount of calories they consume, their metabolic sytem starts to conserve fat and energy and it goes into survival mode. This is why extremely over weight people can eat less and still not lose weight. Instead, they become lethargic as their body tries to conserve as much energy as possible (since it is not being fed expendable energy). You could say that in most cases, gluttony and sloth are side-effects of obesity, not causes.

Taubes also spends time in this section addressing the science of fat regulation (and why carbohydrates make us fat), the health benefits of limiting carbohydrates (while increasing our fat intake), and why diets succeed and fail. The most interesting section was his chapter on "A Historical Digression on the Fattening Carbohydrate." In great detail he reviews the historical understanding of what caused people to be fat (and it wasn't too many calories or not enough exercise). The conventional wisdom in science and medicine once was that fat and protein were not fat producing, but rather that it was "innocent foodstuffs, such as breads and sweets [aka carbohydrates] which lead to obesity."

For whatever reason today, obesity is perceived to be an eating disorder. The science of fat regulation is ignored or considered irrelevant. Instead there continues to be an obsession with dietary fat. This had lead to some ludicrous advice from the likes of the American Heart Association which published a pamphlet advising people, "To control the amount and kind of fat, saturated fatty acids and dietary cholesterol you eat." Instead they recommended that people, "choose snacks from other food groups such as...low-fat cookies, low-fat crackers...unsalted pretzels, hard candy, gum drops, sugar, syrup, honey, jam. jelly..."

Maybe the biggest problem has been the Food Guide Pyramid put out by the USDA.

This first one is from 1992.

It was later updated in 2005.

 

 As you can see, carbohydrates are still emphasized over meats, beans and oils (fats).

 

Finally, I found this food pyramid developed for the Atkins Diet. I thought it was interesting. You can see the top and bottom of the pryamids are reveresed. One has grains and carbs at the bottom, while the other has them at the top. Given our obesity rates in this country, one of them is NOT working.

 

Taubes ends the book with a detailed FAQ based on questions his book "Good Calories, Bad Calories" elicited. He also includes an Appendix which details a healthy low-carb diet developed by Duke University Medical Center.

 

Once again, if you struggle with your weight, or know someone that does, this book will be extremely thought provoking and helpful. I recommend it.

 

*While Taubes is convinced that the current conventional wisdom about what makes us fat is all wrong and that carbs are the culprit not fats, he practically begs the medical establishment to do more research on the subject. In fact, he has recently created the Nutrition Science Initiative. The purpose of NuSI "is to facilitate and fund rigorous, well-controlled experiments targeted at resolving unambiguously many of the outstanding nutrition controversies — to answer the question definitively of what constitutes a healthy diet."