The Diet Delusion

I finally finished reading Gary Taubes’ The Diet Delusion (originally published in the US as Good Calories, Bad Calories: Fats, Carbs and the Controversial Science of Diet and Health). It took me months (I started some time last summer) because it’s massive and unapologetically dense: 460 pages of prose, followed by 45 pages of endnotes and almost 100 pages of bibliography.

This isn’t your typical popular diet book. Taubes is not a nutritionist or lifestyle guru, but a science journalist, and this book is as much about science and the scientific method, and what happens when they meet politics, as it is about what we should or should not eat.

I came across the book when I began reading up on the paleo diet, which I stumbled across by chance and began to follow precisely one year and two days ago. Since then I’ve kept to the diet quite well, apart from extended lapses at home through the summer and over Christmas, when I was too lazy to buy my own food.

But these lapses, if anything, have only convinced me further that the paleo diet is the way to go. Since Christmas, never a healthy time of year for anyone, I’ve pulled out all the stops. I’ve scarcely touched bread, rice or any type of grain or starchy food; my caloric intake derives from some vegetables, but mostly protein and fat – including saturated fat. With gay abandon I ignore those scary red warning stickers on supermarket packaging. I’ve even ditched olive oil except for salad dressing, and now I fry everything, which means most breakfasts and dinners, in lard.

Saturated fat alert!

The result after six weeks is that the Christmas gut has evaporated and I haven’t had a single heart attack. I feel healthy and energetic and I never let myself go hungry. The only time I feel lethargic is when for some reason I have a high-carb meal, like when I had lasagne for lunch yesterday and two hours later the post-glucose crash left me falling asleep on the sofa.

Lard makes you be young and fall in love!

Being an archaeologist interested in human history, I found the basic premise of the paleo diet attractive as soon as I started reading about it, but Gary Taubes has really helped elucidate two things: first, the science of fat metabolism, which explains why the diet works as well as it does; and second, the politics of dietary research, which explains why the diet diverges so starkly from what governments and health experts tell us we should be eating.

This is what Taubes has to say about people who work in nutrition, chronic disease and obesity:

“I believe it is difficult to use the term ‘scientist’ to describe those individuals who work in these disciplines, and I have actively avoided doing so in this book. It’s simply debatable, at best, whether what these individuals have practiced for the past fifty years, and whether the culture they have created, as a result, can reasonably be described as science, as most working scientists or philosophers of science would typically characterize it.”

It’s truly alarming, since we base our personal notions of what constitutes a healthy diet so much on trust.

Taubes explains that obesity is not caused by caloric input and expenditure per se – i.e. the idea that you get fat because you eat too much and/or exercise too little – but on a dysfunction in how the body stores and mobilises fat deposits.

The comedy documentary filmmaker Tom Naughton can explain it better than I can, as he does in Fat Head, which I highly recommend.

None of this is scientifically controversial, but due to politics, peer pressure and lack of communication, the obvious conclusion that eating fewer carbs will promote weight loss has been swamped in the last three decades by the twin misapprehensions that eating fat makes you fat and clogs your arteries, leading to heart disease (it doesn’t), and that chronic obesity is principally the result of a character defect, in other words lack of willpower (it isn’t).

While Taubes’ main focus is on obesity, he also suggests that excessive carbohydrate consumption is a root cause of diabetes, cancer, heart disease, dementia and even premature ageing – the so-called ‘diseases of civilization’. Clearly a lot of dedicated research needs to be done to test these hypotheses, but the possibility is intriguing.

Basically, The Diet Delusion is perhaps the most important book I’ve ever read. I can honestly say that it’s changed my life – and how often can we say that?