The book in one sentence: Gary Taubes argues that fat accumulation is driven by insulin, not calories, and that the “eat less, move more” model has failed for 50 years because it misidentifies the cause.
- What Is Why We Get Fat About?
- What Does Taubes Say About Calories In, Calories Out?
- How Does the Carbohydrate-Insulin Model Work?
- What Does Taubes Actually Recommend Eating?
- Is Why We Get Fat Worth Reading?
- Books Like Why We Get Fat
What Is Why We Get Fat About?
Imagine you’ve spent years trying. You tracked calories. You cut fat. You ate smaller portions and went to the gym five days a week. And you still couldn’t keep the weight off. The official explanation (“you’re doing it wrong, try harder”) starts to feel less like advice and more like an insult.
Gary Taubes wrote this book for you. A science journalist who has won the National Association of Science Writers’ Science in Society Award three times (the only print journalist to receive it more than once), Taubes spent over a decade inside the primary research literature on obesity before publishing Good Calories, Bad Calories in 2007. Why We Get Fat is the shorter, more accessible version of that work. Same argument, fewer footnotes, easier to read in an afternoon.
The argument, plainly stated: you don’t get fat because you eat too much. You get fat because of what you eat, specifically foods that spike insulin, which then signals your fat tissue to store and hold. Overeating and inactivity are not causes of obesity. They are effects of it, or at minimum, responses to the same hormonal dysregulation. Taubes calls this a reversal of the arrow of causation, and it changes everything about how to think about treatment.
The book arrived at a moment when the public health consensus on obesity was near-total and its record was not good. Worth reading in that light.
What Does Taubes Say About Calories In, Calories Out?
He doesn’t say thermodynamics is wrong. That matters, because critics sometimes frame his argument that way. The first law of thermodynamics (energy is conserved) is correct. If you gain fat mass, you have taken in more energy than you expended.
What Taubes says is that this observation explains nothing useful about why it happens or how to stop it.
Saying “you gained weight because calories in exceeded calories out” is like saying a room got crowded because more people entered than left. True. Completely unhelpful if you want to know why, or what to do about it.
More importantly, the two sides of the equation are not independent. Cut your food intake sharply, and your body responds: metabolism slows, body temperature drops, lethargy increases, hunger intensifies. The Women’s Health Initiative enrolled nearly 50,000 women and had 20,000 of them cut roughly 360 calories per day for eight years. Average weight loss: two pounds. Average waist circumference went up. By the arithmetic, they should have lost over 30 pounds in year one. The body compensated at every turn.
“Of all the dangerous ideas that health officials could have embraced while trying to understand why we get fat, they would have been hard-pressed to find one ultimately more damaging than calories-in/calories-out. That it reinforces what appears to be so obvious — obesity as the penalty for gluttony and sloth — is what makes it so alluring.”
The caloric model also carries a moral weight that Taubes finds both unjustified and damaging. If obesity is a failure of energy balance, and energy balance is a matter of choice, then the obese are to blame. Taubes argues this conclusion is wrong, cruel, and gets in the way of actual treatment.
How Does the Carbohydrate-Insulin Model Work?
Fat tissue is not a passive storage container that fills up when calories overflow. Fat is constantly flowing in and out of fat cells, driven by enzymes and hormones. Two players matter most:
- Lipoprotein lipase (LPL): activated by insulin; pulls fat from the bloodstream into fat cells
- Hormone-sensitive lipase (HSL): suppressed by insulin; releases fat from fat cells to be burned
When insulin is chronically elevated, LPL is in overdrive and HSL is shut down. Fat moves in. It doesn’t move out. The rest of the body, denied access to stored fuel, registers this as energy deprivation. You get hungry. You get tired. Not from laziness or weakness. From a hormonal signal that says “store, don’t burn.”
The foods that drive insulin highest and fastest are the most fattening ones:
- Refined flour products: bread, bagels, pasta, cereals, crackers
- Liquid sugars: soda, juice, beer, sweetened coffee drinks
- Starchy vegetables: potatoes, corn, white rice
- Sugar in all its forms (with fructose, processed by the liver, producing a separate set of problems around insulin resistance and triglycerides)
Non-starchy vegetables (leafy greens, broccoli, cucumber, cauliflower) barely move the needle. They are fibrous, digested slowly, and produce modest insulin responses. For practical purposes, Taubes says, they are not fattening.
The reversed arrow
Taubes’s most counterintuitive claim is also the one with the most supporting evidence. He cites George Wade’s rat experiments: female rats whose ovaries were removed became obese rapidly. When food was restricted so they literally couldn’t overeat, they still fattened. Instead of overeating, they became sedentary. The fat accumulation was primary. The behavioral changes were compensation.
“We don’t get fat because we overeat; we overeat because we’re getting fat. It’s a simple but critical inversion of cause and effect.”
If that’s true, then the whole framing of “lack of self-control” as the cause of obesity is backward. The hunger and inactivity that accompany obesity may be biological responses to fat accumulation, not the choices that produced it.
A note on where the science stands now
Taubes published this in 2010. Since then, carefully controlled metabolic ward studies by NIH researcher Kevin Hall have found that when protein is matched and calories are closely tracked, low-carb and low-fat diets produce similar rates of fat loss. The insulin response differs, but under strict conditions this doesn’t translate to dramatically different fat loss.
This doesn’t mean low-carb diets don’t work. In real-world settings they often work better than low-fat approaches, likely because of reduced hunger and fewer cravings. But it does suggest that the carbohydrate-insulin model, as Taubes presents it, overstates the hormonal driver and understates other factors: food reward and appetite regulation in the brain matter too. (Stephan Guyenet’s competing framework, which Taubes dismisses too quickly, deserves its own read.)
Hold the model as a powerful lens, not the final word.
What Does Taubes Actually Recommend Eating?
The practical protocol in the book comes from Eric Westman’s Duke University Lifestyle Medicine Clinic. It is not complicated:
Remove entirely:
- All added sugars, all grain and flour products
- Starchy vegetables (potatoes, corn, white rice)
- All liquid calories (soda, juice, beer, sweetened drinks)
Eat freely:
- Meat, fish, poultry, eggs, full-fat dairy
- Non-starchy vegetables, leafy greens
Do not count calories. Do not restrict portions of permitted foods. Eat when hungry, stop when full. Target under 20 grams of net carbohydrates per day in the early phase (ketogenic territory).
Taubes frames this as less restrictive than it sounds. The foods coming out are nutritionally thin (white bread, pasta, soda, candy). The foods staying in are nutrient-dense. Hunger often decreases once insulin comes down, because the metabolic signal shifts from “store everything” to “burn what’s available.” Many people report the cravings diminish within a week or two.
The hard part is that Taubes presents this as permanent, not a temporary diet. The hormonal environment that drives fat accumulation returns if you return to refined carbohydrates. That’s a real ask, and he doesn’t minimize it.
Is Why We Get Fat Worth Reading?
Read this if you’ve done calorie-restricted diets and found them unsustainable or ineffective, especially if you’ve been told the failure is your fault. Read it if you have metabolic syndrome, prediabetes, or carry most of your weight in your midsection. Read it if you want to understand the biology behind low-carb approaches rather than just being handed a food list.
Skip it if you’ve already adopted a low-carbohydrate eating pattern and are looking for guidance on maintaining it. Skip it if you’re primarily interested in the psychological and emotional dimensions of eating. Taubes has almost nothing to say about that side of things. Skip it if you want a balanced review of all current obesity science.
One honest caveat: Taubes writes like a prosecutor, not a judge. He is marshaling a case, and he does it well. He also dismisses competing theories too quickly (the food reward model, above all), and presents the carbohydrate-insulin model with a confidence that subsequent research has not fully justified. The science has moved since 2010. Read The Hungry Brain by Stephan Guyenet alongside this one if you want the more complete picture.
Still, as a corrective to the shame-based “eat less, move more” narrative, and as an explanation of why insulin matters in fat metabolism, the book holds up. For many readers it lands as a genuine relief: not an excuse, but a better explanation.
Books Like Why We Get Fat
| Book | Author | Best For |
|---|---|---|
| The Hungry Brain | Stephan Guyenet | The strongest competing theory: how the brain regulates appetite and why hyperpalatable food short-circuits it |
| The Obesity Code | Jason Fung | Extends Taubes’s insulin argument and adds intermittent fasting as a practical lever |
| The End of Overeating | David Kessler | Food industry engineering of hyperpalatable foods; complements the food reward model |
| Why We Get Sick | Benjamin Bikman | Deep dive into insulin resistance as a root cause of metabolic disease |
| Food Rules | Michael Pollan | Practical eating principles from a different angle; short, readable, reaches similar conclusions |