Tag: Book-notes

The Science of Obesity

Why We Get Fat

One thing that has always baffled me is how we get fat.

Why We Get Fat by Gary Taubes unearths the biological truth around why we’re getting fat. In the process, Taubes dispels many accepted ideas on weight-loss and nutrition.

While it’s easy to believe that we remain lean because we’re virtuous and we get fat because we lack self-control or discipline, the evidence clearly says otherwise. Taubes methodically tackles conventional (and governmental) wisdom and why it is wrong.

This is a biology book, not a diet book. It’s about the science of what’s happening in our body that makes us fat. Let’s explore Taubes argument.

Is this a simple calories-in calories-out problem?

Do low-calorie diets work? In the short-term yes but overall, no.

“The two researchers who may have had the best track record in the world treating obesity in an academic setting are George Blackburn and Bruce Bistrian of Harvard Medical School. In the 1970s, they began treating obese patients with a six-hundred-calorie-a-day diet of only lean meat, fish, and fowl. They treated thousands of patients, said Bistrian. Half of them lost more than forty pounds.”

They concluded, “This is an extraordinarily effective and safe way to get large amounts of weight loss.” Yet, shortly after, Taubes says “Bistrian and Blackburn gave up on the therapy because they didn’t know what to tell their patients to do after the weight was lost. The patients couldn’t be expected to live on six hundred calories a day forever, and if they returned to eating normally, they’d gain all the weight back.”

So, even if you lose weight on a low-calorie diet, you’re stuck with the what now problem.

What if i just exercise more?

What happens when we increase our energy expenditure by upping our physical activity? Taubes says “Considering the ubiquity of the message, the hold it has on our lives, and the elegant simplicity of the notion-burn calories, lose weight, prevent disease-wouldn’t it be nice if it were true?”

Alas, believing doesn’t make it so. While there are many reasons to exercise regularly, losing weight isn’t one of them.

Taubes looks at the evidence and walks us through a chain of reasoning. The evidence says obesity associates with poverty. In most modern parts of the world, the poorer people are, the fatter they are likely to be. Yet, it’s the poor and disadvantaged who sweat out a living with physical labor. This is one of the reasons to doubt the assertion that expending a large amount of energy on a regular basis makes us fat.

Another reason to doubt the calorie-out hypothesis is the obesity epidemic itself. We’ve been getting fatter for the past few decades which suggests that we’re getting more sedentary. Until the 1970s, that is, before the obesity problem, Americans were not believers in the need to spend leisure time sweating.

In addition, it turns out there is very little hard evidence to support the belief that the number of calories we burn has any meaningful impact on how fat we become. The American Heart Association even calls the data supporting this claim “not particularly compelling.”

A study by Paul Williams and Peter Wood collected detailed information on almost 13k runners and then compared the weekly mileage with how much they weighed year-to-year. As you would expect, those who ran the most tended to weigh the least, but, perhaps unexpectedly, all these runners tended to get fatter with each passing year (even those running more than 40miles a week!)

According to Taubes, the belief in exercising more to weigh less is “based ultimately on one observation and one assumption. The observation is that people who are lean tend to be more physically active than those of us who aren’t. This is undisputed. … But this observation tells us nothing about whether runners would be fatter if they didn’t run or if the pursuit of distance running as full-time hobby will turn a fat man or woman into a lean marathoner. We base our belief in the fat-burning properties of exercise on the assumption that we can increase our energy expenditure (calories-out) without being compelled to increase our energy intake (calories-in).”

This assumption is wrong. We ended up buying into this exercise-more-eat-less story because it feels intuitive, correct, and reinforces our beliefs. We didn’t ask for evidence and none has been forthcoming in the intervening years.

Is it a matter of balancing calories?

No. Weight gain is a gradual process. So once you notice your jeans are getting tight, you can make some smart decisions and cut calories and increase physical activity right? “If it were true that our adiposity is determined by calories-in/calories-out, then this is one implication: you only need to overeat, on average, by twenty calories a day to gain fifty extra pounds in 20 years.” Now think of all the food decisions you make in a day and how impossible it would be, without scientific instrumentation, to balance your food.

Thermodynamics

Wait, what about thermodynamics. The law that says energy can be transformed from one form to another but not created nor destroyed.

“The very notion that we get fat because we consume more calories than we expend would not exist without the misapplied belief that the laws of thermodynamics make it true. When experts write that obesity is a disorder of energy balance—a declaration that can be found in one form or another in much of the technical writing on the subject—it is shorthand for saying that the laws of thermodynamics dictate this to be true. And yet they don’t.

All the first law of thermodynamics says is that “if something gets more or less massive, then more energy or less energy has to enter it than leave it. It says nothing about why this happens. It says nothing about cause and effect. It doesn’t tell us why anything happens.”

Experts think the first law is relevant because it fits neatly with our existing theories about why we get fact—those who consume more calories than they burn will gain weight. Thermodynamics tells us that if we get fatter and heavier, more energy enters our body than leaves it. But the important question, at least from an obesity perspective, is why do we consume more calories than we expend?

One of the other problems with thermodynamics argument is the assumption that the energy we consume and the energy we exert have little influence on each other—that we can change one without impacting the other.

The literature says that animals whose food is suddenly restricted tend to reduce energy expenditure both by being less active and by slowing energy use in cells, thereby limiting weight loss. They also experience hunger so that once the restriction ends, they will eat more than their prior norm until the earlier weight is obtained. (This is the same problem Bistrian and Blackburn encountered earlier).

Another problem with Thermodynamics is that it doesn’t address why men and women fatten differently. This means, at least at some level, bodily functions and possibly genetics play a role.

When we believe, as we do, that people get fat because they overeat, we’re putting the ultimate blame on a weakness of character and leaving biology out of it. This implies that we can generally tell, just by looking at the waistline, which people have strong self-control.

Adiposity

In the early 1970s, George Wade studied the relationship between sex hormones, weight, and appetite by removing the ovaries from rats. The impact was dramatic: the previously skinny rats ate voraciously and became obese. “The rat eats too much, the excess calories find their way to the fat tissue, and the animal becomes obese,” offers Taubes. He continues, “this would confirm our preconception that overeating is responsible for obesity in humans as well. But Wade did a revealing second experiment, removing the ovaries from the rats and putting them on a strict postsurgical diet. Even if these rats were ravenously hungry after the surgery, even if they desperately wanted to be gluttons, they couldn’t satisfy their urge.” The rats still got just as fat, just as quickly. And that is the start of our understanding of why we actually get fat.

The animal doesn’t get fat because it overeats, it overeats because it’s getting fat. The animal is unable to regulate its fat tissue.

A follow-on experiment, where the rats were injected with estrogen after the surgery, resulted in normal behavior. That is, they did not become slothful or obese. Biologically, one of the things that estrogen does is to influence an enzyme called lipoprotein lipase (LPL). When cells want fat they express their interest by “expressing” LPL. If the LPL comes from a fat cell, we get fatter. If the LPL comes from a muscle cell, it gets pulled in and digested as fuel. LPL, according to Williams Textbook of Endocrinology, “is a key factor in partitioning triglycerides (i.e., fat) among different body tissues.”

One of Estrogen’s roles is to inhibit the activity of LPL “expressed” by fat cells. The rats in Wade’s experiments over-ate because they were losing calories into fat cells that were needed in other places. The fatter the rat got, the more it had to eat to feed the non-fat cells. When the body is unregulated, it creates a cycle of getting fatter and fatter.

This, as Taubes says, “reverses our perception of the cause and effect of obesity. It tells us that two behaviors—gluttony and sloth—that seem to be the reasons we get fat can in fact be the effects of getting fat.” It also tells us that influencing LPL (either positively or negatively) has a dramatic effect on how fat we get.

LPL also explains why men and women get fat in different spots and why exercise doesn’t work. In men, LPL, activity is higher in the gut and lower below the waist. In women, LPL is highest below the waist. Bad news though, after menopause, LPL in a woman’s abdomen catches up to the men. As for exercise, while we’re working out LPL activity decreases on our fat cells and increases on muscle cells—so far, so good—because this prompts the release of fat from our fat tissue so that muscles can use this as energy. When we stop exercising, however, the situation reverses. LPL activity on the muscle cells shuts down and LPL activity on fat cells picks up. The fat cells natural tendency is to get back to their previous state.

So what regulates all of this?

Insulin. The LPL on fat cells is regulated by the presence of insulin. The more insulin our body secretes, the more active the LPL becomes on the fat cells, and the more fat that, rather than being consumed as fuel by the muscle cells, gets stored in fat cells. As if designed to ensure we get fatter, insulin also reduces the LPL expressed by the muscle cells (to ensure there is lots of fat floating around for the fat cells). That is, it tells the muscle cells not to burn fat as a fuel.

Insulin also influences an enzyme called hormone-sensitive lipase, or HSL. And this says Taubes, “may be even more critical to how insulin regulates the amount of fat we store. Just as LPL works to make fat cells (and us) fatter, HSL works to make fat cells (and us) leaner. It does so by working inside the fat cells to break down triglycerides into their component fatty acids so that those fatty acids can then escape into the circulation. The more active this HSL, the more fat we liberate and can burn from fuel and the less, obviously, we store. Insulin also suppresses this enzyme HSL and so it prevents triglycerides from being broken down inside the fat cells to a minimum.” This also helps explain why diabetics often get fatter when they take insulin therapy.

Carbohydrates primarily determine the insulin level in the blood. Here quantity and quality are important. Carbs ultimately determine how fat we get. But most people eat carbs so why are some fatter than others? We all naturally secrete a different level of insulin — given the same food people will secrete different levels of insulin. Another factor is how sensitive your cells are to insulin and how quickly they become insensitive. The more insulin you secrete—naturally or with carbohydrate rich foods—the more likely it is that your body becomes insulin resistant. The result is a vicious circle.

Not all foods containing carbs are equally fattening. The most fattening foods are those that have the greatest impact on our insulin and blood sugar levels. These are the easily digestible carbs. Anything made of refined flour (bread, cereals, and pasta), starches (potatoes, rice, and corn), and liquids (beer, pop, fruit juice). “These foods,” says Taubes, “flood the bloodstream quickly with glucose. Blood sugar shoots up; insulin shoots up; We get fatter.”

Here is Taubes in a 70-minute video explaining more.

If you want to learn more about the science behind why we get fat, I recommend brushing up on your biology a little and reading Why We Get Fat. Taubes also wrote Good Calories Bad Calories.

James March: The Ambiguities of Experience

In his book, The Ambiguities of Experience, James March explores the role of experience in creating intelligence.

Folk wisdom both trumpets the significance of experience and warns of its inadequacies.

On one hand, experience is thought to be the best teacher. On the other hand, experience is described as the teacher of fools, of those unable or unwilling to learn from accumulated knowledge. There is no need to learn everything yourself.

The disagreement between those aphorisms reflects profound questions about the human pursuit of intelligence through learning from experience.

“Since experience in organizations often suffers from weak signals, substantial noise, and small samples, it is quite likely that realized history will deviate considerably from underlying reality.”

— James March

March convincingly argues that although individuals and organizations are eager to derive intelligence from experience, the inferences stemming from that eagerness are often misguided.

The problems lie partly in errors in how people think, but even more so in properties of experience that confound learning from it. ‘Experience,’ March concludes, ‘may possibly be the best teacher, but it is not a particularly good teacher.’

Here are some of my notes from the book:

  • Intelligence normally entails two interrelated but somewhat different components. The first involves effective adaptation to an environment. The second: the elegance of interpretations of the experiences of life.
  • Since experience in organizations often suffers from weak signals, substantial noise, and small samples, it is quite likely that realized history will deviate considerably from the underlying reality.
  • Agencies write standards because experience is a poor teacher.
  • Constant exposure to danger without its realization leaves human beings less concerned about what once terrified them, and therefore experience can have the paradoxical effect of having people learn to feel more immune than they should to the unlikely dangers that surround them.
  • Generating an explanation of history involves transforming the ambiguities and complexities of experience into a form that is elaborate enough to elicit interest, simple enough to be understood, and credible enough to be accepted. The art of storytelling involves a delicate balancing of those three criteria
  • Humans have limited capabilities to store and recall history. They are sensitive to reconstructed memories that serve current beliefs and desires. They conserve belief by being less critical of evidence that seems to confirm prior beliefs than of evidence that seems to disconfirm them. They destroy both observations and beliefs in order to make them consistent. They prefer simple causalities, ideas that place causes and effects close to one another and that match big effects with big causes. 
  • The key effort is to link experience with a pre-existent accepted storyline so as to achieve a subjective sense of the understanding.
  • Experience is rooted in a complicated causal system that can be described adequately only by a description that is too complex for the human mind. The more accurately reality is reflected, the less comprehensible the story, and the more comprehensible the story, the less realistic it is.
  • Storytellers have their individual sources and biases, but they have to gain acceptance of their stories by catering to their audiences.
  • Despite the complications in extracting reality from experience, or perhaps because of them, there is a tendency for the themes of stories of management to converge over time.
  • Organizational stories and models are built particularly around four main mythic themes: rationality (the idea that the human spirit finds definitive expression through taking and justifying action in terms of its future consequences for prior values); hierarchy (the ideas that problems and actions can be decomposed into nested sets of subproblems and sub-actions such that interactions among them can be organized within a hierarchy); individual leader significance (the idea that any story of history must be related to a human project in order to be meaningful and that organizational human history is produced by the intentions of specific human leaders); and historical efficiency (the idea that history follows a path leading to a unique equilibrium defined by antecedent conditions and produced by competition.
  • Underlying many of these myths is a grand myth of human significance: the idea that humans can, through their individual and collective intelligence actions, influence the course of history to their advantage.
  • The myth of human significance produces the cruelties and generosities stemming from the human inclination to assign credit and blame for events to human intention.
  • There is an overwhelming tendency in American life to lionize or pillory the people who stand at the helms of our large institutions -to offer praise or level blame for outcomes over which they may have little control.
  • An experienced scholar is less inclined to claim originality than is a beginner.
  • …processes of adaptation can eliminate sources of error but are inefficient in doing so.
  • Knowledge is lost through turnover, forgetting, and misfiling, which assure that at any point there is considerable ignorance. Something that was once known is no longer known. In addition, knowledge is lost through its incomplete accessibility.
  • A history of success leads managers to a systematic overestimation of the prospects for success in novel endeavors. If managers attribute their success to talent when they are, in fact, a joint consequence of talent and good fortune, successful managers will come to believe that they have capabilities for beating the odds in the future as they apparently have had in the past.
  • In a competitive world of promises, winning projects are systematically projects in which hopes exceed reality
  • The history of organizations cycling between centralization and decentralization is a tribute, in part, to the engineering difficulty of finding an enduring balance between the short-run and local costs and the long-run and more global benefits of boundaries.
  • The vividness of direct experience leads learners to exaggerate the information content of personal experience relative to other information.
  • The ambiguities of experience take many forms but can be summarized in terms of five attributes: 1) the causal structure of experience is complex; 2) experience is noisy; 3) history includes numerous examples of endogeneity, causes in which the properties of the world are affected by actions adapting to it; 4) history as it is known is constructed by participants and observers; 5) history is miserly in providing experience. It offers only small samples and thus large sampling error in the inferences formed.
  • Experience often appears to increase significantly the confidence of successful managers in their capabilities without greatly expanding their understanding.

Still interested? Want to know more? Buy the book. Read Does Experience Make you an Expert? next. 

Max Bazerman — You Are Not As Ethical As You Think

Ethical infractions are rooted in the intricacies of human psychology rather than integrity.

Max Bazerman’s book: Blind Spots will certainly make you think about your own actions more objectively.

Briefly, here are some of my takeaways.

  • We engage in behavioral forecasting errors. We believe we will behave a certain way in a certain situation. Yet, when actually faced with that situation we behave differently.
  • We are experts at deflecting blame and rationalizing our behavior in a positive light. A used car salesman can view himself as ethical despite selling someone a car that leaks oil, by noting the buyer failed to ask the right questions (bias from self-interest).
  • People often judge the ethicality of actions based on the outcome (outcome bias). We tend to be far more concerned with and show more sympathy when the actions taken affect “identifiable victims”.
  • Motivated blindness (when one party has an interest in overlooking the unethical behavior of another party) explains the financial crisis (bias from self-interest).
  • Research finds that cognitively busy people are more likely to cheat on a task than those who are less overloaded. Why? Because it takes cognitive effort to be reflective enough to skip the influence to cheat. Our brains are predisposed to make quick decisions and in the process, they can fail to consider outside influences (such as ethical concerns). We also behave differently when facing a loss than a gain. We’re more willing to cheat when we’re trying to avoid a loss.
  • Snap decisions are especially prone to unconscious bias. The less time we have to think the more likely we default to in-group preference (racial stereotypes). When instructed to shoot “criminals” and not unarmed citizens one study found that participants incorrectly shot more black men than white men.
  • Research shows that most people view their own input into a group, their division’s input to the overall organization, and their firm’s contributions to a strategic alliance to be more important and substantial than reality can sustain. Over-claiming this credit is, at least partly rooted in our bounded ethicality. That is, we exclude important and relevant information from our decisions by placing arbitrary and functional bounds around our definition of a problem (normally in a self-serving manner). This is part of the reason we fail to see eye to eye in disagreements — we pay attention to different data.
  • The difference in the way information is processed is often not intentional. Confirmation bias helps our minds absorb information that is in agreement with our beliefs and discount information that may contradict our thoughts. (We can’t remember our previous intentions either; How Our Brains Make Memories).
  • Egocentrism is dangerous when playing a Tragedy of the Commons game (Social Dilemma) such as the one we’re currently playing with debt and the environment as it encourages us to over claim resources.
  • In the end the kindergarten rule of fairness applies: one person cuts the cookie and the other has first pick on which half to eat.
  • In social dilemmas the easiest strategy is to defect.
  • A whole host of societal problems result from our tendency to use an extremely high discount rate regarding the future. One result is that we save far too little for retirement. Over-discounting the future can be immoral too as it robs future generations of opportunities and resources.
  • Compliance programs often include sanctioning systems that attempt to discourage unethical behavior, typically though punishment. Yet these programs often have the reverse effect, encouraging the behavior they are supposed to discourage. Why? In short because it removes the ethical consideration and makes it a business decision. (The number of late pick ups at daycares increase when there is a fine.)
  • When your informal culture doesn’t line up with your formal culture you have blind spots and employees will follow the informal culture.
  • Of course, we’re overconfident so informing us about our blind spots doesn’t seem to help us make better choices. We tend to believe that while others may fall prey to psychological biases, we don’t. Left to our own devices we dramatically understate the degree to which our own behavior is affected by incentives and situational factors.

***

Still curious? Check out Blind Spots. This book will help you see how your biases lead to your own immoral actions. And if you’re still curious try: Bounded Ethicality: The Perils of Loss Framing.

The Art and Science of Asking Better Questions

At the recommendation of Warren Buffett’s Biographer, Alice Schroeder, I’ve been reading The Craft of Interviewing.

Schroeder seems pretty crafty at knowing when, what, and how to ask questions that get to interesting answers.

Given our podcast, The Knowledge Project, I endevor to ask better qeustions. I want to suppress my ego and stop thinking about what I want to say when the other person is talking and let them talk.

I’ve never been taught how to ask questions, which makes me wonder if I’m getting the most out of the questions I do ask.

If you think about it, asking better questions is really just a clever way to steal from the rich and give to the poor. In this case I’m stealing knowledge from someone that has it (them) and giving it to somoene that needs it (me).

I have a lot of smart friends — by smart, I mean incredibly smart, not just plain smart — and I want to maximize the knowledge I gain from this privilege when we’re together

Here are some of the things I dog-eared while reading this book that you might be interested in:

  • The interview, generally, may take two shapes: one, like a funnel, and the other like an inverted funnel. The funnel-shaped interview opens with generalities – “What are the benefits of nuclear warfare, Mr. President?” – then pins down the generalizations – “When and were has it produced those spectacular sunsets that you mention?” The funnel allows the subject some say in the direction of the interview.
  • Sherlock Holmes would have been fond of the inverted-funnel; it opens with hard, fast, specific questions, then ascends to a more general ground. Used appropriately this form can help put people at ease. Another way to put people at ease is to start with the easy questions. (Learn to think more like Holmes.)
  • Don’t ever make someone feel as if he can’t get his point across, no matter how hard he tries.
  • Far too many people ask questions that try to put the spotlight on themselves rather than the person with the information.
  • Avoid two-part, hypothetical, and leading questions.
  • People won’t confess their inner thoughts unless they have proof the person asking those questions is sympathetic.
  • Mike Wallace says “The single most interesting thing you can do in television, I find, is to ask a good question and then let the answer hang there for two or three seconds or four seconds as though you’re expecting more.”
  • Envelope tough questions with “people are saying” because that helps avoid the person responding from thinking the questioner is attacking them. (Blame someone else for the question.) Another technique for this is to imply the question is a playful one, “I’d like to play the devil’s advocate for a moment.” You can also preface the question with praise.

If anyone knows of other books on asking better questions shoot me an email.

Update: We did a whole interview on asking better questions.