燃: 最新研究，揭開身體究竟如何燃燒卡路里、減肥、保持健康！

by Herman Pontzer, 鍾沛君 (Translator)

得跑多遠，才能把一個甜甜圈的熱量完全燃燒？
咖啡或其他超級食物真能「促進」新陳代謝？
運動不會讓你瘦？讓人大吃一驚的「代謝的科學」！

英美亞馬遜分類TOP 1，售出14國語言版權
登上《新科學人》封面故事，《紐約時報》專文報導
一場橫跨演化生物學、生理學和人類學的歡樂之旅
打破「燃脂」迷思，重新認識飲食、運動和代謝的三角關係！

　　撐得過飢荒，卻逃不過肥胖？
　　關於新陳代謝，原來我們都想錯了……
　　▲我們的細胞比恆星更亮眼，同質量下消耗的熱量是太陽的一萬倍
　　▲人到中年，代謝不會變慢，會胖只是因為吃太多
　　▲一個甜甜圈的熱量，至少要跑四點八公里才能完全燃燒
　　▲懷孕的熱量成本總計約八萬大卡，是最極限的人體馬拉松
　　▲運動也不是多就好，過量反而會減損性致或導致經期紊亂

　　▎動再多也沒用！肥胖為何成為現代人的宿命？
　　人的身體一天需要燃燒兩千大卡，所以只要我們多做運動，加大熱量消耗，就能減到理想體重，對嗎？很可惜，答案沒那麼簡單！為解開新陳代謝機制之謎，杜克大學演化人類學教授赫曼．龐策決定從人類最早期的生活型態開始探尋。他深入非洲，露宿於飢餓的獅群旁，與當地狩獵採集部落打交道，收集科學數據；又前往喬治亞的小山村，挖掘人類化石，分析飲食演變。透過冒險般的經歷與超過二十年的研究，終於發現人體代謝的驚人真相！

　　龐策發現，坦尚尼亞的哈札族，為了狩獵採集，一天走上五小時的路，但他們一天的熱量消耗卻和歐美久坐辦公室的白領相去無幾。從長期來看，光靠運動無法增加整體熱量消耗，因為大腦會根據身體活動情況，調節能量分配。大饑荒時，這是有助生存的絕佳演化策略，但在活動量偏低、生活中充斥誘人加工食品的現代社會中，卻將我們帶上注定肥胖之路。

　　▎原來減重這麼簡單？流行飲食法沒告訴你的事
　　但好消息是，減重也比你想像得簡單，不需要市面上各種讓人眼花撩亂的流行飲食，只要把握幾個原則，降低熱量攝取，你甚至用不著餓肚子！書中駁斥了各種減重狂熱的飲食法，諸如原始人、生酮甚至純素飲食。他逐一探討所有飲食法得以減重成功或失敗的原因：關鍵只在卡路里。

　　與此同時，運動仍是必須，雖然它和減重關係不大，但能讓身體功能維持在最佳狀態，讓你長久保有清醒的大腦、良好的心肺功能與活動能力，甚至減少慢性發炎，紓解壓力並改善情緒，降低生殖系統癌症（乳癌和前列腺癌）的風險。每天至少三十分鐘的運動，死亡風險就減少一半；每天一小時的劇烈運動，就能抵銷久坐辦公桌前的負面健康影響。

　　▎生為「火生」物種，你需要正確認識體內的永恆之火！
　　面對外在世界，人類依靠火來鑄造物品、改變地貌、建立文明，甚至走向宇宙；內在也依靠燃燒卡路里而活，新陳代謝就是我們體內的那把永恆之火。或許，我們並不一定如生物學的命名「智人」那般明智，但可以肯定的是，我們都依靠燃燒能量而活，是不折不扣的「火生」物種。

　　揭露真相、叛逆並且從頭到尾都充滿娛樂性，本書將徹底改變你對飲食與運動的理解與看法！

　　【適讀對象】
　　✓有志進行低碳、生酮、原始人等飲食方式以健康管理、減重瘦身的讀者。
　　✓關注營養科學與保健新知、注重飲食安全問題的讀者。
　　✓積極進行健身，想了解如何飲食才能有效增肌減脂的讀者。

Genres: Nonfiction, Health, Science, Nutrition, Food, Audiobook, Fitness

367 pages, Kindle Edition

First published March 2, 2021

Reviews

[Chris Boutté · Rating 5 out of 5]

I've always struggled with my weight, but during my 8-year drug addiction, I put on over 200 lbs. I've been sober for 8.5 years, and I've been struggling to take the weight off. Something that drives me nuts is all of the non-scientific contradictory information about diet and exercise out there, so I decided to check out this book from Herman Pontzer. I must say that Pontzer did an incredible job with this book, and I think it's perfect for a wide range of readers. 

I'm more of a psychology guy than a biology guy, but Pontzer was able to break down how the body functions in a simple way. There are still a few concepts I may need to go back and revisit, but his overall thesis was easy to grasp. What I really enjoyed about this book was how the author dispelled a lot of myths about diets, exercise, metabolism, and more. My only critique is at the end of this book, I personally didn't leave with many solutions, but that's not what this book was about. Fortunately, Herman replied to me on Twitter and recommended some other great books that I can check out.

[Matt · Rating 2 out of 5]

Pontzer frequently digresses into memoir-esque stories about his own personal adventures, which would be distracting enough from the content of the book if they weren't jam packed with his personal opinions and forced / corny jokes.

As for the content of the parts that actually discuss the science of metabolism, the parts that talk about doubly labeled water and the new insights Pontzer and his colleagues have come up with, it's interesting enough. However, Pontzer constantly impugns the research others have found with large scope research that focuses on wide cross sections of humans and then asserts that such evidence disproves a variety of diet modification strategies. Then later, he blithely mentions that there is more complexity than the calories in / calories out simplification he underlines (he mentions that some kinds of fats seem to be handled differently by our body than others, but briskly moves on from the implications that individual variation and macronutrient composition may indeed play important roles).

Beyond these epistemic oversights, he also fails to mention any of the controversy surrounding Ancel Keys' work on the diet-heart-hypothesis and moves on quickly from the topic to continue carping about the superiority of his own views and how they are compatible with Keys'.

That would all be enough on its own, but most of the last 10-20% of the book is given over to a discussion about modern society and climate change and his particular prescriptions for fixing the ills of affluence as well as climate change with little respect to the fact that both of these fields have a deep well of scholarship which is not his particular expertise and that his particular opinions on this seem quite thinly informed.

[Latiffany · Rating 4 out of 5]

For years my exercise routine consisted of waking up at 5:00 a.m. to walk four miles or attend a cardio class. Over the years, my weight crept up and by the end of 2019, I was thirty pounds overweight. I decided to approach losing the weight by focusing on nutrition. I still worked out daily, but I overhauled my diet, focused on portions, and developed the mindset that this is how I wanted to eat for the rest of my life. I didn't cut out any food groups or try popular diets. I focused on eating nutritious foods that kept me full and satiated. I've lost forty pounds and for the most part, I feel amazing. In addition to eating well, I read articles, books and watch videos about nutrition. That is how I found out about this book.

Herman Ponzter explains in detail with science to back his claims, what I figured out through trial and error. Exercise is wonderful for the body. There are so many benefits to be gained from exercise-even mild exercise, such as a daily walk around your neighborhood. However, exercise does not automatically result in weight loss.

There are portions of this book that are a bit technical and exposed me to facts about the brain and the intricacies of the metabolism that I really didn't need to know. Overall, I do think that the language and terms are accessible to readers that believe in science, but aren't very interested in every single detail.

I read a mild criticism about the ending of the book. Pontzer steps away from the inner workings of the digestive tract and discusses how the world around us fits into what we eat, how much we eat, why we eat and the consequences of stuffing ourselves with processed food. I find no issue with raising questions about the cost of potato chips versus the cost of an apple. I think it blends in perfectly.

This is a good read and I strongly recommend it.

[8stitches 9lives · Rating 5 out of 5]

One of the foremost researchers in human metabolism reveals surprising new science behind food and exercise. We burn 2,000 calories a day. And if we exercise and cut carbs, we'll lose more weight. Right? Wrong. In this paradigm-shifting book, Herman Pontzer reveals for the first time how human metabolism really works so that we can finally manage our weight and improve our health. Pontzer's groundbreaking studies with hunter-gatherer tribes show how exercise doesn't increase our metabolism. Instead, we burn calories within a very narrow range: nearly 3,000 calories per day, no matter our activity level. This was a brilliant evolutionary strategy to survive in times of famine. Now it seems to doom us to obesity. The good news is we can lose weight, but we need to cut calories. Refuting such weight-loss hype as paleo, keto, anti-gluten, anti-grain, and even vegan, Pontzer discusses how all diets succeed or fail: For shedding pounds, a calorie is a calorie.

At the same time, we must exercise to keep our body systems and signals functioning optimally, even if it won't make us thinner. Hunter-gatherers like the Hadza move about five hours a day and remain remarkably healthy into old age. But elite athletes can push the body too far, burning calories faster than their bodies can take them in. It may be that the most spectacular athletic feats are the result not just of great training, but of an astonishingly efficient digestive system. This is a fascinating, captivating and deeply insightful look at the science of metabolism and seeks to set right the myths and pseudoscience often perpetuated about eating, weight loss and lifestyle. Written in an accessible conversational fashion and in Pontzer's typical entertaining style, this is an informative, revealing and likely the most definitive read on the topic to date. It will change how you eat, move, and live and leave you with a much more sound understanding of the way our bodies convert food into energy. Highly recommended.

[Alek · Rating 2 out of 5]

The smarmy tone and navel gazing that suffuses this tome cannot make up for any number of useful anecdotes about his adventures:
“We were a clever crew, after all—budding scientists pursuing our PhDs at prestigious academic institutions from around the world. We had the intelligence and temperament to earn competitive spots in top-tier graduate programs and to work our way here”

Btw, did you know he did his PhD at Harvard? Don't worry, he'll remind you:
“I had learned the consensus view in college at Penn State in the 1990s and grad school at Harvard in the 2000s,”
“It was the late summer of 2003, midway through my PhD at dear old Harvard”
“Brian and I were friends from our grad school days at Harvard”
“Dan Lieberman (my PhD advisor at Harvard)”

[Nicole Westen · Rating 3 out of 5]

I have a lot of mixed feelings about this book. I was prepared to give it five stars at the beginning, but at the end I found myself having to put the book down every three or four pages in order of pace out my frustration. I've settled on three because the science is sound and I think incredibly important. We honestly think we know how our bodies work, but the reality is we don't know a whole lot at all. Pontzer does a fantastic job of expanding that knowledge, but once he steps outside of the strictly biological and into the social, things get messy. Cross-discipline collaboration is important.
I'll start of with what I liked before I get started in on my ranting criticism.
Pontzer discusses his experiments in how apes use the energy we get from our food. The study includes many other apes, like gorilla's and orangutans, and also humans that choose to live in what we might consider 'pre-modern' society, such as hunter-gatherer groups. The information that we all burn the same amount of calories, regardless of lifestyle, was fascinating. There is nothing special in terms of metabolism between ourselves and hunter-gatherers like the Hadza. Pontzer discusses how incredibly adaptive our bodies are when it comes to burning energy, and keeping such 'energy expenditures' as he calls them, within a specific range. I loved that he took down the Paleo diet, which I've always considered a bunch of bunk. The idea that humans don't need carbs is just stupid. In the context of history we always discuss the rise of complex civilizations in terms of a staple grain (or tuber in some cases). Famines are caused by a failure in the staple grain crop. If carbs were so unimportant to our diets, then all past famines should not have been as severe. Humans, as Pontzer explains, have an opportunistic diet. We eat what is available in our environment. Peoples living in the far north, like the Inuit and Saami people, eat meat heavy diets because plants do not grow well. Groups that live in areas that lack large game animals eat more plants and insects. I do agree with some of the advice offered, humans were made to move, and most of us in modern societies don't move enough, and we need to find a diet that is sustainable and healthy, not these bizarre, super restrictive diets.
But here is where I diverge from a lot of the advice or conclusions the author draws. First of all, I found a contradictory message in the book. I think some of that might have been Pontzer attempting to reconcile what he had learned with our society's incredible weight bias. Serious, we have a problem, we fat shame pregnant people! Pontzer discusses how good our bodies are at managing the energy we consume, if we eat too much, our bodies attempt to burn it off, storing it is a last resort. So if you eat more than your body needs for essential functions in a day, it will shunt it offer to other functions. When you begin to expend a lot of energy on physical activity your body dials back on the energy allotted to other functions, like reproduction. He even cited a study by Kevin Hall, which followed the metabolism of dieters from the Biggest Loser. These people, even though they were a 'healthy weight' (what is that anyway?), had the metabolism of someone undergoing severe starvation. When we SEVERELY cut back our calories, our bodies go into survival mode and slow energy burn as much as possible. But Pontzer still claims that america's obesity problem stems from eating too much food and not moving enough. Look at the Hadza (who he almost always uses for comparison), they don't eat the sugary processed junk we have, and look at how much they 'work out' each day. In fact, Pontzer suggests caloric reduction to lose weight, despite pointing out that 2000 calories a day are what a child burns, and adults need much more energy, and that when we restrict our energy intake our bodies try to save energy by turning off 'non essential' functions. We do need to move more, but Pontzer's suggestion that we are all lazy and coddled by the modern world compared to the Hadza is a case of comparing apples to oranges. Pontzer speculates that if it won't make us look good in a swimsuit (eg lose weight) Americans won't exercise. For starters, you can live a more active lifestyle without 'exercise'. Engaging in physical activities that you find rewarding, like sports, are much more appealing than running in place for an hour. The idea that we won't make time to exercise because we're lazy doesn't acknowledge that americans work longer hours than any other developed country, and we have fewer rest days as well. Pontzer also acts as though all of these lifestyles are actual choices, ignoring the gaping differences in culture between Americans and the Hadza that can easily account for weight differences. Stress for starters. Pontzer describes a young man who had stayed in camp for a few days in a row because he had been feeling unwell. Never once was it mentioned he was worried that he would go hungry because he couldn't hunt for himself, because for the Hadza sharing food is a given, as opposed to the idea in america where if you don't work you don't eat. Pontzer mentions briefly that poverty and food deserts are a problem, but that's it. Google Obesity Poverty Paradox. Our poorest people are also our fattest, which flies in the face of the idea that obesity is a sign of over-consumption. How do you over consume when you don't have consistent access to food? And Pontzer's suggested solutions to food deserts are overly simplistic. Just tax sugary food to make it more expensive and make fresh fruit and vegetables cheaper. Really? Poverty is the problem. You can only lower the cost of something so much before the farmer who grows it doesn't make enough money to keep the farm running and himself fed.
The finally, he blatantly ignored all of the other differences between american and Hadza environment. How much pesticide was on those berries the Hadza women gathered? How much chemical fertilizer was in the soil they dug their tubers from? How many hormones had the zebra eaten that the Hadza men hunted? How much of their food and drink come from plastic containers that leech chemicals like BPA, BPS, and BPF? We also have access to a lot of medications that, while they do help us immensely, tend to have weight gain as a side-effect. About one quarter of all people on an anti-anxiety or antidepressant will experience weight gain, which is also a side effect of hormonal birth control pills for women. The point is we have an incredibly different social structure, and cultural values, from the Hadza that can account for weight factors, as well as exposure to chemicals of our own making that we are just now starting to realize might have negative effects on our health. For the record, Europe and Canada more strictly control the use of BPA and other chemicals in food packaging than America (science has shown that BPA affects us at levels way lower than what the american government has considered 'safe'), and Europe has also banned the use of hormones in food animals and the importation of meat that has been exposed to those hormones. I feel like Pontzer should have stuck to the science, instead of trying to make broad social claims by comparing two radically different cultures, without sufficient understanding of sociology, traditional anthropology, and considering other differences in our environments, other than availability of food and cars.

[Debra · Rating 2 out of 5]

I had such high hopes for this book. Had to sift through much information ( honestly though interesting, I skimmed a lot of it) to locate what I wanted. About 15,000 steps to maintain weight, eat less than 2,000 calories ( more like 1500 or less) to lose weight.

[Ali · Rating 5 out of 5]

A fun, authoritative & witty guide to the latest science of metabolism, exercise & weight loss
Have you ever slept just a few hundred yards from a pride of hungry lions to gather data, with just a thin nylon tent between you and becoming breakfast? Herman Pontzer has. In "Burn", he lives to tell the tale of trying to keep up with bafflingly badass Hadza hunter-gatherers and steel-livered Georgian paleoanthropololgists. The result is a masterwork of popular science writing: authoritative yet accessible, iconoclastic, and funny as hell.

The book is primarily about energy: the evolution of how humans acquire, use, and store it; the mechanisms for turning energy into work; how other animals do it differently; and how we sometimes thoughtlessly squander it. In the process, he upends some popular myths about diet and exercise.

For example, his research shows that the Hadza, who every day move around for ~4 hours and 15,000 steps, use the same amount of energy as couch-potato North Americans. What?!? How is this even possible? I'm still wrapping my head around this, but the definitive double-labeled water experiments don't lie. Humans have "constrained energy expenditure", meaning that you only burn so many calories a day no matter what you do. Our extremely effective "metabolic compensation" simply shifts calories around so we break even at the end of the day no matter how much we move.

For practical purposes, this means that you basically can't lose weight through exercise. Reducing caloric intake is the only way. Nevertheless, the manifold health benefits of exercise still make it the single most healthful activity we can do, as Prof Pontzer takes pains to emphasize.

I appreciate Pontzer's vivid prose with evocative imagery and analogies that even a 10-year old can understand. I have no idea how he summarized all of college biochemistry in 2 pages while still making sense, but I'm sure glad he did. I particularly laud his deft use of technical terms like "hooey", "BS" and "poo", sometimes when dispatching bad science and fad diets like Paleo, low-carb keto, and raw foodism into the rubbish bin of nonsense. He's the anthropologist who's actually gathering the data in the African bush, freezing urine samples in liquid nitrogen and hauling them back. Don't know about you, but I'm going to listen to working scientists with real data before armchair engineers, journalists, and self-styled diet gurus.

Finally, it's been a while since I laughed out loud multiple times reading a science book. The gleefully irreverent humor lives in the hangover poetry, the punny section titles ("Mitochondria and the O2 joy", "It's alimentary, my dear Watson"), and the Hadza language lessons.

Out there, there's a lot of contradictory information on diet, exercise, and metabolism. For literate primates who use energy and want to disentangle truth from speculation without having to confront hungry lions, Prof Pontzer has done us a great service in compiling all we need to know in one enjoyably informative package. Read "Burn" to learn how your body really works.
-- Ali Binazir, M.D., M.Phil., Happiness Engineer and author of The Tao of Dating: The Smart Woman's Guide to Being Absolutely Irresistible, the highest-rated dating book on Amazon, and Should I Go to Medical School?: An Irreverent Guide to the Pros and Cons of a Career in Medicine

[emily ♡ · Rating 4 out of 5]

Im not usually a non-fiction reader but I really enjoyed reading this book. Pontzer covers a wide range of topics, from the intricacies of the human digestive system, to the evolution of the human species, to the norms of modern living which are slowly destroying our health. Reading this will leave you completely questioning the sustainability of your lifestyle, but, like, in a good way.

[Brent Saindon · Rating 5 out of 5]

This is sort of a weird book. It is billed as a diet book, but really is a wonderful summary of work on human evolution and metabolism. It does much to debunk many of the diet myths in our society, while providing a basic scientific framework for health.

The stories of archaeological excavation and the time spent with the Hadza are remarkable in their own right. This book was a joy to read.

[Morag Murray · Rating 5 out of 5]

I learnt a lot reading ‘burn’. The topic of calorie burn interests me as a runner and a calorie counter.

From the synopsis I gleaned that much of what I thought about exercise and calorie burn was incorrect, and I was intrigued to find out more.

This book is heavy on research so it feels very authentic and one to be taken seriously.

Chapters are a good mix of storytelling around the authors time with the Hazda community of hunter gatherers he has researched along with the science and ‘take home’ messages we can all learn from.

While this book is pretty intellectual and definitely challenged me in that respect, I felt I did get the gist.

This book really makes us think about lifestyle and rethink our relationship between (highly palatable) foods and obesity. Some great points about exercise are included, and while it may have less bearing on our weight the importance of exercise and movement in our daily lives is encouraged.

Knowledge is power, and this is definitely a book that it is well worth reading for anyone who wants to know the truth behind nutrition and exercise based on real science and without any fads!

My thanks to Netgalley, author and publisher for the opportunity to review this book in exchange for an advance copy.

[Stephanie]

It's rare that I'll read a non-fiction/self-help/research based book and think, "that wasn't long enough." Aaaaaaand... that's still the case with Burn.

I was optimistic about this book from sentence one, as the author weaves personal anecdotes well with his research findings. However it became quickly clear to me that the scope he gives is just... too large.

When you write a research book that promises on the cover to change the way people think about burning fat / diet culture, you have to deliver to the impatient masses (aka, me). The tagline of the book is literally "New research blows the lid off how we really burn calories, lose weight, and stay healthy." But Herman Pontzer gave so much background information to try to color the context of his research, but it just caused his research to get lost in the noise.

Ultimately it was soooo much scientific information I didn't care about. Because the tagline that was promised wasn't delivering.

[Santhosh Guru · Rating 5 out of 5]

One of the best books related to fitness and health (in a broad category). I picked it up because of Keith Rabois' recco.

Like my favorite book Sapiens, it digs deep into the evolution of human beings from apes and very beautifully sets the context. Very crisply articulates about the importance of metabolism and demystifies a lot. My key takeaway from this book are these two points:

1. Exercise doesn’t change the number of calories you burn each day, but it does change how you spend them—and that makes all the difference.
2. Exercise won’t keep you thin, but it will keep you alive.

It took sometime for me to wrap my head around the fact that an Olympic athlete and a normal person's "daily energy expenditure" is more or less the same. Herman Pontzer writes so good on this and cites many research about metabolism. So the exercise does nothing to weight loss but necessary for living a vital life.

But the most tough pill to digest is the take on diet. Herman argues that keto, low-fat, vegan all diets are just calories, YMMV based on the total calorie count. This is hard to accept for me as I was influeneced a lot by Gary Taubes' school of thought, keto and low-carb. But Herman has engaged with Gary on keto and explains why it works for some and how to think about food and diet in a wholesome manner.

This is truly a keystone book for me that has given a new lens to look at fitness, diet and exercise. Fantastic read. Highly recommend it.

[Olena · Rating 5 out of 5]

Хто очікує одразу ж порад як схуднути мусить спершу продиратись крізь нетрі біологічних знань, термінів та розрахунків. Серед них також про еволюцію людини та викопні рештки, тобто як метаболізм встановився еволюційно та який раціон був у наших предків.

В основі вчення про людський метаболізм є дослідження його на тваринах, зокрема у приматів, проте є низка досліджень і на людях.

Завдяки книзі у мене освіжились власне університетські знання про травлення та метаболізм.

У визначенні метаболізму автор акцентує не на самому обміні речовин а на витратах енергії, спалених калоріях.

Тут стверджується, що люди в середньому однаково витрачають калорії незалежно від фізичної активності. Має значення лише баланс - якщо людина споживає більше ніж витрачає, тоді набирається вага. Проте якщо навпаки - споживає менше, тоді організм реагує посиленням голоду. Цей механізм встановився в процесі еволюції. Але зрештою це є єдиний спосіб скинути вагу - споживати менше. Основна причина зайвої ваги - переїдання.

Цікаво про сучасну їжу - вона дуже смачна і вмикає багато систем винагород в мозку, тому не переїдати стає неможливо. І ще - сучасні харчові продукти є такими, що посилюють смакові якості та пригнічують ті поживні речовини, що дарують відчуття ситості. Їжа смачна та апетитна, але не насичує.

Існує багато дієт, які часто суперечать одна одній і тому важливо знайти таку, яка буде ефективною саме для вас. «Ефективний раціон - той, завдяки якому ви можете досягти здорової ваги й підтримувати її, не почуваючись голодними».

Попри те, що фізична активність не впливає на вагу, вона добре знижує реакцію на стрес. Виснажливі ж тренування можуть втручатись в нормальне функціонування репродуктивної системи, але також контролюючи рівні репродуктивних гормонів вони знижують ризик розвитку онкології цієї системи.

Хороша книга, хоч і було дещо зайве.

[Pedro Loos · Rating 4 out of 5]

Esse é um daqueles livros que eu colocaria na lista “livros que mudaram a minha maneira de pensar”. Eu não sou um cientista do metabolismo ou nutricionista, apenas tenho um background de física. Eu digo isso porque não tenho como verificar se todas as afirmações ditas pelo autor são verdadeiras, mas no que diz respeito à física e termodinâmica, o autor possui um excelente entendimento.

Leitura recomendada! Eu não esperava me divertir e aprender tanto lendo um livro sobre metabolismo.

[Laura McDougall · Rating 5 out of 5]

If you're looking for an insightful new weight loss plan, then this is not the book for you. In fact, it's pretty much bad news on the weight loss front, because bodies have biologically obvious reasons to set calorie burn limits and our economically driven society doesn't want you to be satiated. It wants you eat more, because that means buy more. The take-away is eat whole foods and move lots and avoid weight gain in the first place. It's really hard not to walk away from this book feeling hard done by, and so, so mad at society.

On the other hand, for everyone who tried to manage their weight and found the calorie in-calorie out mantra basically useless, this book has a practical and logical explanation for that experience. We're not weak, we're human. We're human in an environment we created that's hostile to our own biological needs.

I appreciated the perspective shift, considering all our modern conveniences as outsourced or externalised calorie burn. It sheds a whole new light on sustainability for our planet and sustainability for humans in their every day lives.

This book is funny, challenging, weirdly beautiful and in some parts, haunting AF.

[Andy Lee · Rating 5 out of 5]

This book significantly changes how I view diet and exercise. Learning about the constrained energy expenditure model is a large part of this.

Our body, specifically our hypothalamus, is constantly working to achieve homeostasis. Working to take in and expend around the same amount of kilocalories each day. Exercise has little long-term effect on our weight because our bodies will adjust to the additional expended calories over time. Losing weight is nearly all about eating less calories than you expend.

Exercise is still important because of the constraint energy expenditure model. Calories devoted to exercise our calories not expended on unnecessary and possibly devastating activities in your body such as inflammation, stress responses, and excess reproductive hormone production.

Burn is a book that's accessible to everyone. Written with a bit of humor, the science behind the author's learnings is easy to grasp, which is no small feat. A must-read no matter what your interests.

[Trace Nichols · Rating 3 out of 5]

Calories in - calories out theory. No food restrictive diets work. Exercise won't help you burn away more than you would. Basically we are who we are. Not sure I buy into everything he purports. Much of his science is from data collected from a hunter-gatherer people called the Hadza who lead (and have always led) a very different lifestyle than people of western civilizations. They are too limiting to have the big reveal ah-ha moments that then apply to all the human race.

[Nikita Umov · Rating 5 out of 5]

Trenn ei aita kaalu langetada. Inimeste päevane energiavajadus ei muutu intensiivsuse tõstmisel. Või kui muutub, siis mitte märgatavalt. Ainus võimalus kaalust alla võtta on vähem süüa. Üks peamiseid põhjuseid, miks me üle sööme on ultratöödeldud toit, mis sõidab üle kõikidest ajusignaalisest.

See ei tähenda, et trenni ei peaks tegema. Trenni tegevad inimesed on rõõmsamad, elavad kauem ja tervemana.

Väga hea raamat, mis seletab väga hästi metabolismi!

[Joanne · Rating 3 out of 5]

Admittedly I picked this book up hoping to come away with a magic pill for weight loss. Instead, I learned more about anthropology and organic chemistry. At the end of the day, no matter what you’ve learned about historical anthropology or the body’s chemistry, if you eat more than you burn then you’re going to get fat. Choose your calories wisely.

[Alexandra Chubachi · Rating 3 out of 5]

I learned some things. I knew some things. I scanned a lot.

[Clark Herring · Rating 5 out of 5]

One of the best non fiction books I have ever read. The author covers wide range of subjects and reminds me of Bill Bryson except that he is a better writer, I know that Bill Bryson is a very, very good writer. I came for the analysis of different dieting strategies and stayed for the discussion about how human bodies turn food into calories, the metabolic pathways and a discusion how human metabolisms differ from other mammals and other apes. The other topics include how humans and our nearest relatives burn calories and their relative life scale versus other mammals. He then dives into a discussion of evolution and its probable effect on our metabolism. He ended up discussing the effect of exercise on our metabolism, as well as how true endurance athletes metabolize energy. I know that this sounds like a lot but it was extremely well organized and the topics flowed naturally.

[Donna Herrick · Rating 5 out of 5]

Studying human metabolism illuminates climate change

A very enlightening look at metabolism. How we have evolved, the differences and similarities between human hunter-gatherer communities and modern urban communities, the future of human communities in light of the climate change that our energy usage gas wrought.

[Markus · Rating 5 out of 5]

Apparently physical activity has no real effect on weight loss. The general energy expenditure calculations we have come to know (2000 kcal per day and such) have relied on some vague extrapolations and the understanding of the energy expenditure of the human body has been a kin to a simple machine to which you put energy in and and get equivalent energy out.

In the 1950's a method called doubly labeled water method was invented that measures the energy expenditure in an organism more directly, more accurately but the problem was that it was extremely expensive so human studies were pretty much out of the question. In the decades since, the method has become cheap enough to study humans so here we are. What are the results?

The first thing they discovered, studying the Hadza tribe with this method was that the daily energy expenditure among the Hadza is the same as for men and women in the U.S. and Europe despite the fact that the amount of daily physical activity for these tribespeople was several times greater than in the Western world taking into account body size, fat percentage, age, sex and what have you. They have repeated several similar studies, for example one with women who had never trained regularly and had them train for a half-marathon and eventually had them running about 40 km per week. For these women the daily energy expenditure increased about 120 kcal, which is about 25 grams of chocolate. For a 70 kg person, running 40 km, burns about 2800 kcal of energy (400 kcal per day), so how is that possible?

Essentially, the human organism adapts to increased physical activity, directing energy use to different organs/activities and keeps the energy burned in calories roughly the same regardless of physical activity. The point is that humans are not simple machines that work like steam engines, rather we are dynamic and efficient biological robots that have evolved over millions of years and to understand the workings of this, we need to do a little bit more thinking and rely on more accurate data.

The author goes on to explain how hypothalamic hunger and satiety network is one of the systems responsible that keep the energy expenditure stable regardless of physical activity and how the basal metabolic rate varies by responding to losses and increases of body weight and the sense of hunger (my brain is tired, so I can't explain that part more accurately, but maybe later). Eventually the only realistic way to maintain your ideal body weight, since physical activity is out of the question, is to keep consumed calories low. That is most easily done by eating natural unprocessed foods that quickly give you a sense of satiety and don't urge you to overeat. So pretty much 90% of what is sold in stores is ruled out, sadly.

Also, physical activity still lengthens our lives, reduces the chance of most diseases severalfold and increases the quality of life but it just doesn't work in reducing bodyweight. That is done through watching what and how much you eat.

[Rich Yavorsky · Rating 4 out of 5]

"Our bodies don’t work like simple fuel-burning machines because they aren’t products of engineering, they’re products of evolution."

In answering questions I didn't know I had about human evolution, global economics and my bowels, Pontzer PhD leaves me informed, concerned and hopeful with his metabolism research as documented in Burn. Come for the nutrition lesson, stay for the tales from the African bush, and see the world through your dinner plate.

Our metabolism's "Constrained Energy Expenditure" as proved-and-christened in this book is counterintuitive and truly startling. While Burn offers no magic bullet regarding weight loss (beyond refuting magic bullets themselves--hooray!), it does calibrate one's expectations regarding diet and exercise. Calibration is the antidote to disappointment, and disappointment is the bane of dieting. (And yes, please eat right and exercise!) Diets can work, but calories-in-calories-out: one can't escape the laws of physics. It's seemingly harder to escape your brain's foxy hypothalamus, the master controller of your appetite who constantly moves the goal posts as a function of a workout or missed meal, and is easily blinded by the calorie-dense industrialized foods of modern society. Knowing is half the battle however, and Burn provides this knowledge in spades.

As an amateur distance runner/nutritionist for the past 30 years, I found the collegiate-level shakedown of how your gut works (Chapter 2's "subway map") wildly satisfying. What so complex about a carb? Where are ketones, if not in my meal? Are antioxidants and free radicals a thing? Etc. I've long intuited healthy eating; it's great to know how it works at the cellular level.

The anthropological arc of this book illustrates the moderate history of human diet, but ends with a imperative in fossil fuels/calorie macroeconomics: a revealing prism through which one must view our 21st-century world if we expect it to be present for our grandchildren. Your meal, the refrigerator, the store, the delivery truck: it's ALL calories, paid for by the dwindling remains of dinosaurs.

The humor/puns in the book are sometimes distracting, sometimes engaging. Perhaps in a second revision I would edit so as to not lose non-US readers. Audiobook is hard due to deep technical detail and charts; print recommended.

"The world is on fire. Start your pieces in the paper that way. Just say in big letters 'The World Is On Fire.' That will make 'em look up." --Joe Welling (Sherwood Anderson), Winesburg, Ohio

I raise my doubly-labled glass to the future work of Dr. Pontzer and his team. May you forever stay healthy as a Hazda (minus the dysentery, of course).

[carol · Rating 4 out of 5]

Since I was 11 I was told to watch my weight & what I eat so I wouldn’t become fat. Not going to blame my mom for the start & forever tumultuous relationship with food & my weight bc in the 80s we still believed in a woman’s worth being tied to her looks & her ability to be married. Luckily for me I didn’t fully buy into this narrative.

Fast forward 34 years later & I’m about 50 pounds overweight & have lost & gained those 50 pounds many times over. I decided in my mature middle age to really dig & find out why this was the way it is & this book came across as if it might provide some answers & help me make an informed decision about how to handle my weight & food.

And I feel satisfied with the information this book provided. Because I’ve basically been on some type of starvation diet on and off for 30+ years I’ve basically willed my body to be bigger. The body is a highly tuned complex machine that wants to survive. It’s not so easy as calories in & calories out bc your body learns & adapts as we want & expect it to. At this point if you are of the heavier set, if you want to be thinner & stay thinner you will have to work harder and eat less than a person of your same ideal weight who has never “dieted.”

And the conclusion for me is I’m not going to make an overly conscious effort to try & lose weight. I’m not hindered by my weight in the very least. But I will exercise more. This book will go into detail about how pointless exercise is for weight loss, but my biggest takeaway from this book is make sure you exercise! We are designed to exercise & we can exercise at any size & there are hundreds probably thousands of benefits for working your heart & body.

So if your slim, your gorgeous, don’t change a thing. And if you’re curvier, you’re gorgeous, don’t change a thing. Get a move on, drink lots of water, & fill up on fruits & veggies. Do it not for vanity’s sake but for life’s sake. Because you are worth it.

[Karel Baloun · Rating 5 out of 5]

Pontzer is a leading global expert on measuring metabolism, having collaborated on thousands of measurements over a dozen years in over a dozen species, from his phd research, to postdoc stints with archologists and tribes in tanzania and congo, to following extreme athletic events. He is perfectly positioned to answer the question "how much energy do bodies burn", accross species and activities. "Homo Energeticus."

I read and like Gary Taubes, and Pontzer knows him and loosely collaborated with him too. He doesn’t bash Taubes, but notes that the latest research tends against his insulin response to fat hypothesis, and that leptin/ghrelin is more of a mental process than a food biochemical one. He posits that rather than sugary food being the only problem, excessively delicious foods of all kinds deliver too many calories. Yet he agrees that for specific people low sugar diets have reversed type-2 diabetes.

Burn is based on a decade of original research, and makes a few massive testable claims. Partly explains why caloric restriction is useful for longevity. He loves his own research, so his details can occasionally feel excessive. He’s a scientist though, not a popular writer, and his insights require zero recipes or nutrition protocols.

Burn says to exercise in order to reduce the injury of excess calories. While still insisting that it is better to not eat too many of any kind of calories. His diet advice is common sense to achieve that goal: lots of high fiber less calorie dense foods that make you feel full. And that insufficient protein means feeling hungry. He takes time to attack raw food diets.

As an ultra athlete, this research resonated strongly with my experience, and he has been a guest on prestigeous running podcasts.

[Charles Cai · Rating 3 out of 5]

I think most people would find some new pieces of information in this book/relevant takeaways, but I was interested in metabolism in the context of extreme endurance events and there was only a brief section that covered it. I also think a lot of the claims are very generalized and don’t necessarily apply to everyone; my main takeaways from this book were:
-If you want to lose weight, you need to consume less calories than you burn (simple enough right?)
-Exercising alone isn’t a good way to lose weight, the reason being that your body has a relatively fixed total energy expenditure (which I’m not sure I believe in extreme cases), which means if you start exercising more, your body will expend less energy on other bodily functions (like immune system and reproduction), thus keeping your overall expenditure constant
-Processed foods are the reason we have an obesity problem since they are high in calories and low in satiety; no one gets fat just eating vegetables
-Exercise does have a lot of other benefits like improved heart health, preventing weight gain once you’ve lost weight, and building muscle (which in turn has higher energy expenditure just maintaining this muscle)

[Christian · Rating 4 out of 5]

It takes a while for this book to get its stride because there’s a lot of science he covers to lay the groundwork for the rest of the book to make sense. He breaks down the metabolic engine of our body really well although admittedly, I don’t think much of it will stick without re-reading the first two chapters again.

But that provides a great foundation for the truly groundbreaking insights he shares on how our bodies maintain a base metabolic rate regardless of how much energy we expend. This book definitely delivers on its claim to upend everything we’re told about weight loss; and he does it with tremendous research.

The book loses its way a bit in the final chapter when he touches on energy beyond just humans and into food production and climate change. It does help round out the picture of energy, but that’s better covered in other books and deviated too far away from his central theme of human metabolism.

Overall, though, this is a must-read for anyone who wants to better understand nutrition and metabolism.

[Ginta · Rating 5 out of 5]

Ar “Burn” man gāja kā šūpolēs. Sākumā šķita, ka vairāk par 3 zvaigznītēm nebūs. Kāpēc tik daudz par šimpanzēm, orangutāniem, Āfrikas ciltīm, ja solīts bija stāsts par to, kā mēs dedzinām kalorijas. Un tad notika “aha”! Saslēdzās antropoloģija, cilvēka evolūcijas ceļš un metabolisms. Ļoti informatīvs un izsmeļošs materiāls, ja gribas labāk saprast savu organismu, kas ietekmē svara izmaiņas, kā to uzturēt veselīgā līmenī.

📈Daudz atsauces uz pētījumiem, faktiem, datiem, piemēriem.
⛔️Nav universālas diētas, kas atrisinātu mūsdienu rietumu pasaules veselības problēmas. Ne keto, ne vegan, ne kāda cita.
🥵 Fizisko aktivitāšu intensitāte neveicina svara zudumu. <- zinātniski pierādīts
🥇Metabolisms grūtniecības laikā ir pielīdzināms tai intensitātei, kādā darbojas profesionāli triatlona sportisti (medaļa visām grūtniecēm 💪).


❓Viens gan iztrūka pilnai bildei - hormonālās sistēmas darbība un tās sasaiste ar metabolismu. Kā zināms, hormonu darbība ļoti var ietekmēt svara izmaiņas.