Notes on

Why We Get Fat: And What To Do About It

by Gary Taubes

| 15 min read


Introduction: The Original Sin

we don’t get fat because we eat too much and move too little, and that we can’t solve the problem or prevent it by consciously doing the opposite.”

The traditional way of thinking (calories in vs calories out) has shown repeatedly that it doesn’t work.

Fat accumulation is regulated by insulin.

More insulin leads to more fat in our fat tissue - and less insulin leads to less fat in our fat tissue.

“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.”

It is hormones, enzymes, and growth factors that regulate our fat tissue — “just as they do everything else in the human body, and that we do not get fat because we overeat; we get fat because the carbohydrates in our diet make us fat.”

It’s ultimately the result of a hormonal imbalance, not a caloric one — “specifically, the stimulation of insulin secretion caused by eating easily digestible, carbohydrate-rich foods: refined carbohydrates, including flour and cereal grains, starchy vegetables such as potatoes, and sugars, like sucrose (table sugar) and high-fructose corn syrup. These carbohydrates literally make us fat, and by driving us to accumulate fat, they make us hungrier and they make us sedentary.

But these are very typical in a western diet. So what do we eat instead?

Answer: “stay away from carbohydrate-rich foods, and the sweeter the food or the easier it is to consume and digest—liquid carbohydrates like beer, fruit juices, and sodas are probably the worst—the more likely it is to make you fat and the more you should avoid it.”

“Carbohydrate-rich foods—bread, pasta, potatoes, sweets, beer—were seen to be uniquely fattening, and if you wanted to avoid being fat, you didn’t eat them.”

Why Were They Fat?

On science

“What sets science and the law apart from religion is that nothing is expected to be taken on faith. We’re encouraged to ask whether the evidence actually supports what we’re being told to believe—or what we grew up believing—and we’re allowed to ask whether we’re hearing all the evidence or just some small prejudicial part of it. If our beliefs aren’t supported by the evidence, then we’re encouraged to alter our beliefs.”

It’s not overnutrition that’s the problem; it’s malnutrition.

The Elusive Benefits of Undereating

After eight years of eating at a 360 calorie deficit, women in a study lost (on average) only 2 pounds each. Their average waist circumference increased. So the weight they lost wasn’t fat; it was muscle.

But what if they lied about their food intake? Or it wasn’t measured correctly?… Or perhaps, it’s just that we do not lose weight by reducing calorie intake.

It’s like a scientific experiment that we want to force the results for. We’ll keep trying to do it the same way each time - even though it fails - just because we believe it so much. “Well, maybe I didn’t do it right. Maybe I need to go harder.”

“Eating less—that is, undereating—simply doesn’t work for more than a few months, if that.”

The Elusive Benefits of Exercise

How do you work up an appetite? You do more physical work and exercise. Well, then, isn’t it kind of weird that we recommend eating less - but exercise more, which makes us much hungrier?

Just working out and not changing our diet, and the exercise giving us a 150 calorie deficit, would result in us losing a pound. But not in reality. Because we’re exercising, we also eat more - which definitely cancels out the 150 calories.

It was Jean Mayer who advocated for “exercise = fat loss”. But his theories never had any hold. Not on humans nor animals.

The same argument is made for weight lifting. Building more muscle will increase metabolism, but will also make you hungrier. So you’ll eat more anyway.

Why are those with demanding physical work overweight? Are we sure it’s just because “they eat too much”? “If factory workers can be obese, as I discussed earlier, and oil-field laborers, it’s hard to imagine that the day-to-day expenditure of energy makes much of a difference.”

A study by some Danish researchers: Five pounds / no change after 1.5 years of marathon training and marathon running.

A horrible abuse of science: “As for the researchers themselves, they invariably found a way to write their articles and reviews that allowed them to continue to promote exercise and physical activity, regardless of what the evidence actually showed.”

This chapter is saying that exercise is not healthy. It’s just not very effective for losing weight.

The Significance of Twenty Calories a Day

A question I had while reading:

So far so good with the book. But is the concept of calories in / calories out completely out, or are we assuming no regulations or controlling of the diet? If we lose fat by controlling insulin, how do we gain muscle? That must require additional energy = more food. Later in the book, this began making a bit more sense. You can obviously still gain muscle — it’s just fat that is regulated by insulin. Continue eating clean; and get sufficient ‘material’ for building the muscles.

As a general note, this chapter was good at illustrating the message of the book, but had some (in my opinion) poor examples; so I’m not including my notes here. The basic premise of this chapter was that if you overeat by just 20 calories a day, for a long enough period of time, you’ll gain lots of weight. The same is true if you reverse it (-20 calories a day). But this is obviously not true. Like I said, this chapter is just making ridiculing the calories in vs calories out thinking with an example.

Why Me? Why There? Why Then?

Summary: our genes and hormones determine when and where our fat will be stored

Thermodynamics for Dummies

Eating less makes us reduce energy expenditure by being less active and by slowing down energy use in cells. That limits weight loss. We will also feel increased hunger; so when the restrictions end, we eat more than we usually do, thereby regaining the weight lost.

“eating less and/or exercising more is not a viable treatment for obesity or overweight and shouldn’t be considered as such. It might have short-term effects but nothing that lasts more than a few months or a year. Eventually, our bodies compensate.”

The Laws of Adiposity

“We don’t get fat because we overeat; we overeat because we’re getting fat.”

The First Law

“Body fat is carefully regulated, if not exquisitely so.”

“A final argument for the careful regulation of body fat is the fact that everything else in our bodies is meticulously regulated. Why would fat be an exception? When regulation breaks down, as it does in cancer and heart disease, the result is often fatally obvious. When people accumulate excess fat, this tells us that something has gone awry in the careful regulation of their fat tissue. What we need to know is what that defect is and what to do about it.”

The Second Law

“Obesity can be caused by a regulatory defect so small that it would be undetectable by any technique yet invented.”

The Third Law

“Whatever makes us both fatter and heavier will also make us overeat.”

A Historical Digression on “Lipophilia”

“Both gluttony (overeating) and sloth (sedentary behavior) will be the side effects of any regulatory derangement, minor as it may be, that diverts too many calories into fat tissue for storage.”

A Primer on the Regulation of Fat

It is the quality and quantity of the carbohydrates that we consume that ultimately determine how much fat we accumulate.

Fat is always going in and out of your fat cells, continuously flowing around in your body. They provide a significant portion of the fuel that your cells will burn for energy.

This chapter provides a great explanation of how fat is regulated. I won’t try to explain it, so if you want to know: read the book.

“The one thing we absolutely have to do if we want to get leaner—if we want to get fat out of our fat tissue and burn it—is to lower our insulin levels and to secrete less insulin to begin with.”

The vicious cycle: As we fatten, our energy demand increases, and so does our appetite — especially for carbohydrates. Why them? Because they’re the only nutrient our cells will burn for fuel when insulin is elevated. “If we’re predisposed to get fat, we’ll be driven to crave precisely those carbohydrate-rich foods that make us fat.”

What We Can Do

“it’s carbohydrates that ultimately determines insulin secretion and insulin that drives the accumulation of body fat. Not all of us get fat when we eat carbohydrates, but for those of us who do get fat, the carbohydrates are to blame; the fewer carbohydrates we eat, the leaner we will be. ”

Not all foods containing carbohydrates are equally fattening.

The most fattening foods are those with the greatest effect on our blood sugar and insulin levels. The concentrated sources of carbohydrates (and especially those that we can digest quickly):

  • “Anything made of refined flour (bread, cereals, pasta)”
  • “Liquid carbohydrates (beers, fruit juices, and sodas)”
  • “Starches (potatoes, rice, and corn)”

“These foods flood the bloodstream quickly with glucose. Blood sugar shoots up; insulin shoots up. We get fatter. ”

Carbohydrates from leafy vegetables are fine. They are bound up with indigestible fiber and take much longer to be digested and enter our bloodstream. We also have to eat much more of these to get the same load of carbohydrates.

“if we’re predisposed to put on fat, it’s a good bet that most fruit will make the problem worse, not better.”

“The very worst foods for us, almost assuredly, are indeed sugars—sucrose (table sugar) and high-fructose corn syrup in particular”

Injustice Collecting

The message of Adiposity 101 is simple enough: if you’re predisposed to get fat and want to be as lean as you can be without compromising your health, you have to restrict carbohydrates and so keep your blood sugar and insulin levels low. The point to keep in mind is that you don’t lose fat because you cut calories; you lose fat because you cut out the foods that make you fat—the carbohydrates. If you get down to a weight you like and then add these foods back to the diet, you’ll get fat again. That only some people get fat from eating carbohydrates (just as only some get lung cancer from smoking cigarettes) doesn’t change the fact that if you’re one of those who do, you’ll only lose fat and keep it off if you avoid these foods.”

The foods we love the most are those that will make us fat. But it also makes sense; the foods that we prefer are those that quickly supply energy to the cells — easily digestible carbohydrates.

All foods trigger a response in the ‘reward center’ part of the brain — “that is targeted by cocaine, alcohol, nicotine, and other addictive substances”. But especially sugar. Sugar is immensely addictive.

The cycle and how to break it

“Now, how’s that for a vicious cycle? The foods that make us fat also make us crave precisely the foods that make us fat. (This, again, is little different from smoking: the cigarettes that give us lung cancer also make us crave the cigarettes that give us lung cancer.) The more fattening they are, and the more predisposed you are to get fat when you eat them, the greater the cravings. The cycle can be broken, although it requires fighting these cravings—just as alcoholics can quit drinking and smokers can quit smoking, but not without constant effort and vigilance.

Why Diets Succeed and Fail

“What Adiposity 101 ultimately teaches us is that weight-loss regimens succeed when they get rid of the fattening carbohydrates in the diet; they fail when they don’t. What the regimen must do, in essence, is reregulate fat tissue so that it releases the calories it has accumulated to excess. Any changes the dieter makes that don’t work toward that goal (reducing the fat and protein consumed, in particular) will starve the body in other ways (of energy, and of protein needed to rebuild muscle), and the resultant hunger will lead to failure.”

A Historical Digression on the Fattening Carbohydrate

Straight from the book:

Foods to be avoided:

  • Bread, and everything else made with flour …
  • Cereals, including breakfast cereals and milk puddings
  • Potatoes and all other white root vegetables
  • Foods containing much sugar
  • All sweets …

You can eat as much as you like of the following foods:

  • Meat, fish, birds
  • All green vegetables
  • Eggs, dried or fresh
    • Cheese
  • Fruit, if unsweetened or sweetened with saccharin, except bananas and grapes

Does high-fat low-carb diets increase the risk of heart disease?

“This advice and the shunning of low-carbohydrate weight-loss diets might make sense if dietary fat did indeed cause heart disease, as we’ve been hearing now for fifty years. But there has always been copious evidence suggesting that this obsession with dietary fat is misdirected—another case of the health authorities fooling first themselves, and then the rest of us, because they thought they knew the truth about a subject in advance of actually doing any meaningful research.”

Following Through

Summary on most best-selling books that give dietary advice (based on the same logic that this book provides): “refined carbohydrates, starchy vegetables, and sugars are fattening; don’t eat them, don’t drink them.”

There is no one-size-fits-all prescription for your diet. We’re different, so what works for some might not work for all. Maybe you only have to reduce carbohydrates a bit, or maybe you have to eliminate them completely. Find whatever works for you.

“Whichever group you fall into, though, if you’re not actively losing fat and yet want to be leaner still, the only viable option (short of surgery or the prospect that the pharmaceutical industry will come through with a safe and effective anti-obesity pill) is to eat still fewer carbohydrates, identify and avoid other foods that might stimulate significant insulin secretion—diet sodas, dairy products (cream, for instance), coffee, and nuts, among others—and have more patience”

It takes time to reverse poor dietary habits, just as it took time to accumulate them (and do the damage). So be patient.

Restricting carbohydrates makes you less hungry.

Restricting carbohydrates makes your energy expenditure increase.

Three approaches for implementation

Approach one

Establish an ideal amount of carbohydrates that you would eat in a day and follow that. It might make the transition from (primarily) burning carbohydrates for fuel to fat easier. Regulate as necessary.

Approach two

Go cold-turkey and eliminate carbohydrates.

Short-term side effects might occur, but that’s all it is; short-term.

Approach three

A mix of the two previous. Start by lowering carbohydrate intake immensely (to zero/almost zero). When you’ve lost the weight necessary, you can increase it a bit more again — reintroducing the foods you’ve been avoiding.

But be careful here; don’t fall back into old habits. You’ll just get fat again.

Why conventional diets don’t work

“If a diet requires that you semi-starve yourself, it will fail, because (1) your body adjusts to the caloric deficit by expending less energy, (2) you get hungry and stay hungry, and (3), a product of both of these, you get depressed, irritable, and chronically tired. Eventually you go back to eating what you always did—or become a binge eater—because you can’t abide semi-starvation and its side effects indefinitely.”

Continuing to eat carbohydrates

Why you might want to eliminate carbohydrates completely, rather than allow yourself a bit:

“If you continue to eat some of the fattening carbohydrates or allow yourself some sugar (or even, perhaps, artificial sweeteners), though, you may always have the cravings. You may always have what Stephen Phinney refers to as “intrusive thoughts of food.” Anecdotal evidence suggests this is the case, and that’s all we have to go on.”

“The implication is that for some, at least, long-term success may be more likely if no compromise is allowed. If you do compromise and eventually return to eating these carbohydrates in quantity, the only reasonable response if weight loss remains your goal will be to try again, just as smokers might try to quit numerous times before they ultimately succeed. There’s no other viable option when you find yourself eating fattening carbohydrates again and regaining weight. Try to quit again, or at least cut back to some minimal level.”

Short term side effects (keto-adaption) and what to do about it

“When you replace the carbohydrates you eat with fat, you’re creating a radical shift in the fuel that your cells will burn for energy. They go from running primarily on carbohydrates (glucose) to running on fat—both your body fat and the fat in your diet. This shift, though, can come with side effects. These can include weakness, fatigue, nausea, dehydration, diarrhea, constipation, a condition known as postural, or orthostatic, hypotension—if you stand up too quickly, your blood pressure drops precipitously, and you can get dizzy or even pass out—and the exacerbation of pre-existing gout”

“The more technical term for carbohydrate withdrawal is “keto-adaptation,” because the body is adapting to the state of ketosis that results from eating fewer than sixty or so grams of carbohydrates a day. This reaction is why some who try carbohydrate restriction give it up quickly”

How to counter the side-effects:

“The reaction can be countered, as Phinney has noted, by adding sodium back into the diet: taking a gram or two of sodium a day (a half to one teaspoon of salt) or drinking a couple of cups of chicken or beef broth daily, which is what Westman, Vernon, and other physicians now prescribe.”

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