Gary Taubes latest book is titled “The Case For Keto” (TCFK), his first book for a specific nutritional strategy, low carb high fat, although he’s certainly introduced the idea in his earlier work. Gary continues his string of worthwhile titles on nutrition topics, well researched and readable. While I was dissatisfied with his exposition of some of the science, on balance I found the book provides a useful guide to anyone who would like to improve their health through diet. For many people, TCFK and “Why We Get Fat” (WWGF) are the two best books from Gary for understanding how diet affects our health and what to do about that. I should explain that I’ve been in contact with Gary since I heard him on Talk of the Nation in the summer of 2012. He recommended I read WWGF, and shared copies that I distributed to family and friends. Many of us adopted the low carb high fat diet he covered briefly as an alternative to conventional high carb low fat recommendations. We all got the same results–better health. I’ve been learning about nutrition ever since, reading an array of books and journal articles. Most of those are listed in the Sources section of this website.
TCFK starts by laying out Gary’s perception of the problem. That is unwanted and uncontrollable fat deposition, which can lead to obesity. He says there is a fundamental, almost willful rejection of research and writings in science from those in basic and applied fields that indicate obesity is a disorder, not an absence of self control. It is a function of how your body metabolizes sugar, not some equation that counts calories consumed versus energy expended.
He strongly makes the point that blaming obesity on overeating is circular logic. He quotes a famous Harvard nutritionist, Jean Mayer– “To attribute obesity to ‘overeating’ is as meaningful as to account for alcoholism by ascribing it to ‘overdrinking.’” German and Austrian researchers in the early part of the 20th Century viewed the problem as a disorder of fat accumulation and metabolism. This research community disappeared with the rise of fascism and the Second World War. Their work was written in German, largely ignored by a new generation of American researchers in the post-war years. Without good scientific support, a paradigm that weight management was a matter of self control of consumption combined with exercise to “burn calories” came to dominate.
Gary repeatedly points to genetic differences in people’s propensity to gain fat. He discusses the tendency for people who are naturally lean to ascribe their leanness to proper behavior, not good genes. I must admit I fell into that group, thinking incorrectly that if one exercised enough and ate a “balanced” diet one’s weight would take care of itself. What Gary doesn’t mention is that according to researchers like Dr. Richard Johnson, there’s also an age component. As we get older, we get better at metabolizing the sugar fructose. When I was in my 20s, I ran a string of 20 mile runs in the space of two weeks to drop 5 pounds. When I was in my 40s after my weight had crept up perhaps 10-12 pounds, I put in 70 miles a week for six weeks and didn’t lose an ounce. The creeping gain continued until I changed my diet at age 60. I quickly dropped 10 pounds and the creeping stopped. When I hear young, lean, athletic people expound on what they and you should eat, I say to myself “oh well.”
TCFK discusses some of the history that led to the medical, nutrition, and public health professions ignoring research that suggested what you ate and what your genetic propensities for handling carbohydrates in your diet dictated your response to a high sugar/carb diet. Instead, they’ve fallen into the mechanistic paradigm that measures calories consumed versus supposed amounts expended. He spends a chapter showing how that arithmetic breaks down on careful analysis. I would add from a biological perspective, the idea that an animal somehow measures calories consumed is nonsensical. In reality, when an animal consumes its species normal diet, weight is stable regardless of amount of activity.
Gary proposes that fat deposition is a hormone controlled feedback system. In that model diets high in sugar and easily digested carbohydrates (which are turned into simple sugars before your intestine absorbs them) elevate blood glucose. That causes your pancreas to release insulin. Insulin signals the cells of your body, in particular your fat cells, to take up glucose. The fat cells turn that glucose into more fat. He points out that this is well known science, covered in the textbooks. It most certainly applies to fat deposition in the fat cells, which are mostly under your skin. A high carb diet causes many, perhaps all people to keep eating because of the way sugar affects satiation feedback loops. Fat keeps being deposited. I was surprised by the emphasis in that section solely on fat deposition. That’s one symptom of a complex of pathologies that the medical literature has labelled “metabolic syndrome.” Thinking back, I realized he was reprising themes from WWGF. Since then, I’ve read scientific and biomedical articles and books by researchers in the field, most notably Dr. Robert Lustig and Dr. Richard Johnson, that focus on metabolic syndrome and its cause, which they say is consumption of the sugar fructose. Rick also says that high glucose consumption in a short period of time causes glucose to be converted to fructose. Almost all the sugar people consume in food or drink is about half fructose and half glucose–table sugar and high fructose corn syrup.
Fructose metabolism drives fat deposition in and around the liver, plus subcutaneous deposition throughout the body. Metabolic syndrome is in fact a normal mechanism by which animals can quickly turn sugary foods into stored fat, but that stops when the sugary foods (fruits, berries, etc.) are gone. Gary documents the phenomenal increase since the early 19th Century in individual sugar consumption year round, which is not normal, turning metabolic syndrome into a pathology of excess. The signs of metabolic syndrome include excessive weight gain, the fat deposition in and around the liver and other organs, loss of insulin response, elevated blood pressure, diabetes, heart disease, and stroke. Later in the book, Gary does touch on metabolic syndrome and fructose, but not in the level of detail I would prefer. He doesn’t reference the work of Johnson or Lustig. This isn’t crucial to the basic message of the book, but I think he would have a stronger case if he included them.
The second half of TCFK provides a lot of new information about the practicalities of a healthy nutrition plan. It makes the book well worth the time to read it. Gary focuses on the benefits of a low carbohydrate, high fat diet (LCHF) in which carb intake is low enough to trigger the body to switch from using glucose for normal metabolism to using ketone bodies derived from fat (ketosis). He also discusses the other way to induce ketosis–stop eating for awhile. That can be anywhere from a few hours to a few days. Throughout the book, he presents the experiences of people who have tried to change their nutrition habits. For this book, he interviewed a number of physicians who had learned to advocate LCHF for their patients, which usually meant they had adopted that for themselves as well. Over and over, the people had tried conventional high carb diets with poor results, then tried LCHF. “As if by magic” they lost weight and sustained the loss. He includes the experiences of a couple of physicians who say they are able to manage a low carb, high fat diet using vegan sources, which I haven’t seen documented elsewhere.
He discusses whether sustaining a LCHF diet could have negative health implications that aren’t understood. He concludes the data we have doesn’t support that claim. Here’s a quote from a woman who was quite successful with LCHF induced weight loss in response to someone who got upset she ate less than 20 grams of carbs per day– “Finally, I was like, dude, do you really believe I was healthier 90 pounds heavier than I am now?” I would add that the program I’m personally familiar with, the Diet of Hope, provides a six week medically supervised intensive introduction to healthy low carb eating, with open ended follow up possible. Patients are asked to track protein, not carb consumption. They are given individualized meal plans. They are measured repeatedly. All patients who sustain the program get positive results that include improvement in blood test measures of health. Those positive results are sustained for as long as the patients stick with the diet, which is presented at the outset as a lifestyle change, not a temporary diet.
Chapter 14, Defining Abstinence has specific direction regarding what to eat and what to avoid. I largely agree with the lists. However, I have a genetic defect that predisposes me to a condition similar to age related macular degeneration in my mid-70s. At the advice of a friend who keeps his carbs under 25 grams/day, I consume some wild blueberries and tart cherries every day. As I mentioned earlier, I probably have a higher than average tolerance for carbohydrates while sustaining ketosis. Ketosis is inherently anti-inflammatory, but certain berries are high in anthocyanins, compounds that have additional anti-inflammatory properties specific to the eyes and perhaps the skin (i.e. conferring some UV resistance). My intraocular pressure readings (a measure of inflammation) dropped to the lowest levels since my first visit to my current eye doctor 20 years ago. With lowered pressure my eyes changed shape and my contact lens prescription was changed to match, less near-sighted. Most important, pictures of my retina showed them to be remarkably smooth, which my eye doctor commented on because it is unusual for a person with my condition. Apparently bumpy retinas are a precursor to mitochondria in retina cells of the macula popping, releasing cytokines, and causing apoptosis (cell death) of their host cells. That may be related to long term stress from elevated systemic uric acid caused by metabolizing the sugar fructose.
Chapter 17, The Plan is the exposition of Gary’s six keys–
- Guidance. Finding a physician with whom you can work.
- Goals. Establishing reasonable objectives.
- Abstinence.
- Contingencies. Do this right and expect the unexpected.
- Adherence. Sustaining what you started in a world that makes it as difficult as possible
- Experimentation. Knowing which levers to pull when LCHF/ketogenic eating does not sufficiently correct your health.
This is a reasonable strategy. I was nowhere near this organized when I started a ketogenic diet, but I wasn’t trying to correct an identified health or weight problem, I was interested in the supposed performance benefits for endurance activities. It never occurred to me to consult a physician, nor did any of the people in our trail running group who went to keto. If you aren’t diagnosed with one of the components of metabolic syndrome for which you are taking medication, you can find resources and groups on the Internet without working with a physician. However if you are taking a prescribed medication, changing your diet abruptly carries risks. Dr. Dietmar Gann explained to me that with his Diet of Hope patients, it is important to work with their referring physicians to drop the doses of insulin and/or other medications quickly as the diet took effect. He specifically commented diabetic patients could go into an insulin coma if the dose wasn’t stepped down rapidly. You may or may not have physicians available that will work with you well on diet changes and medication. If not, there are online programs such as Virta Health, which Gary references, and The Real Meal Revolution, started by the famous exercise physiologist Dr. Tim Noakes. I know a number of people who have done well using the Diet of Hope program, but can’t comment on the efficacy of the online programs.
Gary ends the book with a chapter he titles “Caution with Children.” Overall, he does recommend working with children to lower their carbohydrate consumption. The Ganns treat children in the Diet of Hope program with good success, but they say it’s important the family work on diet together.
There’s a lot more in the book than I’ve covered here. It’s pretty information dense. Gary does make some comments regarding the idea that a healthy diet may be more important than a plant based diet even though it’s not necessarily as good for the planet. I disagree. Turning grasslands, which cows and other ruminants like bison can consume, into row crop monoculture is ecologically disastrous, but that’s beyond the scope of this review.
Gary and I have discussed my perceived gaps in the book. He knows about the work of Richard Johnson et al, and is aware of the counter arguments relative ecological impacts of plant and animal agriculture. I’m not sure to what degree he’s researched the details of either area. For this book, he chose to concentrate on core science and concepts that he’s comfortable and familiar with. The result is still a very well reasoned, practical guide to improving health with a diet that has worked well for millions of people.