On January 29, 2014, I was privileged to view a screening of Donal O’Neill’s new hour-long documentary, “Cereal Killers.” The Kickstarter-backed film follows O’Neill (producer and protagonist) through Cape Town as he embarks on a medically-supervised departure from the routine Western diet. Hewing to the immersive one-month “Super-Size Me” formula, O’Neill flips the modern USDA food pyramid on its head and eliminates practically all carbohydrates from his diet. In their stead, he makes fat the bedrock of his energy intake for four weeks. O’Neill precisely calibrates his nourishment: 70 percent calories from fat, with the balance made up largely from protein and fiber from produce. (If you’re curious how he gets to 70 percent calories from fat, I suggest you see the film. I was delighted that nuts were a keystone element of his diet.)
The results of the experiment are remarkable. (Spoiler alert!) O’Neill loses weight, enjoys increased energy, improves his athletic performance, and reduces his measures on a medley of biometric risk tests to “pristine” levels. The last point is especially pertinent: O’Neill’s motivation to change his diet stems from his grapple with the prevalence of heart disease and metabolic disorder in his lineage. O’Neill’s father – a lifelong elite athlete –suffered a mid-life heart attack, which forced O’Neill to confront difficult questions about his own diet and health. By the end of the experiment, O’Neill’s physicians are delighted to assure him that he has taken his once-elevated risk of heart disease (among other things) down to nil. At the core of this film are some profound questions about ability to influence our own mortality.
The Shifting Science of Nutrition
Also at the core of this film is an unremitting demonization of simple carbohydrates. The biometric outcomes of O’Neill’s foray are truly significant, and a new consensus of scientific opinion is aligning that helps us understand why. In recent years, a repentant parade of cardiologists has emerged in collective mea culpa, pronouncing that the true primary driver of the obesity and heart disease epidemics is not, as once thought, the consumption of fat, but rather the prominence of refined carbohydrates in our diets. (With heart disease, omega-6-rich oils can also cause serious issues. But many of the fats we have castigated in the past – such as those from butter – don’t appear to actually cause heart issues.) The science behind these assertions is illuminating, and I will leave it to the experts to elucidate further: Dr. Robert Lustig is a highly potent anti-sugar crusader, as is Gary Taubes*, a science journalist and the author of the truly exceptional book “Why We Get Fat.” In short, our heavy consumption of refined carbohydrates stimulates chronic inflammation in the body, the production of low-density LDL cholesterol (the cause of arterial plaque), and a cascade of maleficent health effects: metabolic disorder, cancers, Alzheimers, and other serious ailments.
The ubiquity of sugar and processed carbohydrates in our most beloved food products is no mystery. While O’Neill doesn’t dwell for long on why he chose breakfast cereal as the titular boogieman for his film, it’s the perfect product upon which to focus skepticism of refined carbs. Michael Moss details the history of the cereal industry in his penetrating work of investigatory journalism, “Salt, Sugar, Fat.” While reading it, I was amazed to learn that the gaudy boxes I conned my parents into buying me as a kid contained cereal with between 40 percent and 70 sugar by volume. As those cereals soak into their milk medium, they create a rapidly digestible liquid injection of glucose, which, despite having more nutrients, is metabolically not all that different from soda. When we consider that such cereals are the first thing that many of us put into our bodies for thousands of mornings as we grew up, it’s no wonder that we ended up with millions of obese and sick kids.
Moss also describes how sugar creates a commanding mechanism of reward and dependency in our brains. The way sugar stimulates our pleasure centers is nearly identical to, and just as strong as (particularly in children), the addiction profile of many illegal drugs (and tobacco). For anyone with a sweet tooth who blindly craves a hit of saccharine bliss after every lunch and dinner (like me), you understand how powerful – if seemingly innocent – sugar urges can be.
“Cereal Killers” highlights the way a person must eat if they are intent on avoiding all sugar and highly processed foods. With refined carbs and the types of oils found in packaged meals considered “out of bounds,” O’Neill spends a considerable amount of time cooking for himself and carefully selecting fresh meals outside of his home. He takes some flak from a friend for championing a diet that is expensive and out of reach for people who live in “food deserts.” But O’Neill’s path is instructive in important ways: he nobly seeks out “perfect” whole foods (eggs are a favorite), eats a sizeable volume of vegetarian-friendly stuff (leafy greens, berries, nuts), and adopts a laudable conscientiousness about what he is putting in his body. (As a side note, one thorny issue raised by this movie is how much animal fat and protein O’Neill consumes to reach his macronutrient goals. I think that if someone wants to emulate the diet, the provenance of their fat and protein is largely a question left to personal preference. There are many vegetarian sources of both.)
One recurring thought I had as I watched the film was: If we have a reflexive cultural disdain for fat, how do we reorient that instinct? Doesn’t dietary fat face a big marketing problem? Indeed, it is difficult to grasp that fat is not really what has been making us fat. We have been taught that fat in diet equals fat in the body, and this belief reverberates with a pleasantly simple logic. But there is not a scientific link between weight gain and high volumes of fat in a calorie-balanced diet (meaning calories ingested = calories burned). However, there is evidence that eating high volumes of simple carbs in a calorie-balanced diet can cause weight gain (this has to do with glucose spikes, insulin response and energy storage). We increasingly understand that not all calories affect us equivalently. (Sadly, the legendary Marion Nestle does not acknowledge the science explaining how differently sugar and processed carbohydrates behave in the body. She is a strict calorie-balancer, but, to my knowledge, has not taken a stance on the mix of macronutrients that make up our diets.)
One promising means of marketing fat is its role in superior athletic conditioning. “Cereal Killers” makes a compelling case that athletes who replace carbohydrates with fat can achieve sustained increases in performance. This, too, upends the traditional paradigm of carbs being an athlete’s best friend.
There are two elements to the performance increase. First, removing inflammation-causing carbohydrates from our diet allows our bodies to heal and recover faster. In the film, University of Cape Town professor Tim Noakes (a legendary runner and former condemner of dietary fat) giddily reviews O’Neill’s post-experiment markers of inflammation (white blood cell count and c-reactive proteins). Noakes points out that O’Neill’s body is generally healthier not because fat was inherently good for him, but rather because carbohydrates were so bad for him – particularly given O’Neill’s genetic reactivity to carbs.
Second, replacing carbohydrates with fat results in greater energy access during prolonged workouts. Athletes that principally consume carbohydrates tend to suffer from spikes and crashes in blood glucose and muscle glycogen. At the film screening I attended, physician Dr. Steve Phinney explained how athletes can train their bodies to burn fatty foods and fat stores in the body instead of relying on constant infusions of carbohydrates. Achieving this state of metabolic processing (known as ketogenesis) results in a far more stable and balanced energy load.** (Personal note: I think this is a pretty extreme diet, and takes time, deeper knowledge, and controlled experimentation to achieve. Anyone who wants to become ketogenic should do more research. Most “weekend warrior” athletes do fine using carbohydrates in their training regimen.)
For the non-athlete, though, the motivation to adopt a higher-fat diet has to come from elsewhere. Certainly, a yearning for better health could be a motivating factor, but, as I have written elsewhere, simply having a desire for improved health is not always a sufficient condition for a major dietary change. That said, the anti-sugar backlash is spreading (see: multi-year declines in soda sales), and low- or no-sugar snacks are flourishing in the marketplace. The Paleo diet is popular in part because of its low-carb mentality, and a slew of startups have emerged to satisfy demands from that demographic. I believe the food industry has a big role to play in creating more demand for high-fat, high-protein, low-carb foods, by developing attractive products as consumer consciousness of the harm caused of processed carbohydrates grows.
Whether those companies can successfully market higher contents of certain types of dietary fats remains to be seen. Any well-intentioned food company will run headlong into fat-phobic consumers. During the “low-fat” craze of the 80’s and 90’s, many eaters were conditioned to see fat as a blinking red light on the nutrition label. The recent growth in sales of almonds, pistachios, and avocados, for instance, is because those industries were able to surmount a consumer education threshold and brand their products as delivery vehicles for the “good kind” of fat. Consumer acceptance hinged on folks’ recognition that there was a “good kind” of fat in the first place, and that realization was galvanized by research at universities and non-profits. As more high-quality nutritional science touts the virtues of eliminating sugar and simple carbs, the food product landscape should follow on – and help drive – consumption of better products.
I have little doubt that “Cereal Killers” will help promote the high-fat/low-carbohydrate diet, if for no other reason than O’Neill is a physical specimen who, by virtue of his very physique, resoundingly overturns the popular “dietary fat = body fat” paradigm. O’Neill loses weight during the experiment, even with a very light exercise regimen. In short, he helps make a case for the vanity impact of cutting out carbs and ramping up fat intake. Aspirational self-image is a powerful driver of behavior, so just seeing O’Neill live out the experiment presents a tantalizingly adequate burden of proof. (The documentary only follows O’Neill for 28 days, but I can attest that, many months after filming and sticking to the diet, O’Neill still appears hale and spry, and still speaks highly of his overall health and test results.)
It’s important to note that O’Neill is cognizant of the caloric density of fat (nine calories per gram, versus four calories per gram in protein and carbohydrates), and keeps his total daily caloric intake equal to, or under, his total output. That is a part of why he doesn’t gain weight. What this means is that O’Neill probably spends more money to take fewer bites of food – a proposition that many American consumers will likely flinch at. And the South African people that hear O’Neill talk about his diet generally react in revulsion at the prospect of ditching sugar and grains altogether.
I think “Cereal Killers” deserves a place in the conversation about what changes need to take place in the standard American diet. It’s a powerful case study in just how off base our consensus opinions about food have been. When a person can eliminate the foundational category of the USDA food pyramid*** from his diet, and not only survive, but thrive, you have to pause and reflect. Moreover, when the body of science supporting his decision strongly indicate that simple carbohydrates have been the principal fuel behind our Western obesity epidemic, you have to wonder why the federal government has created an infrastructure of subsidies and regulations that make processed foods so bountiful and cheap.
I expect that we’ll see a proliferation of demand for more whole foods and foods with less sugar and refined carbohydrates – or at least more whole and complex grains. “Cereal Killers” should help coax the public in a praiseworthy dietary direction.
* Taubes and colleague Peter Attia have founded a 501(c)(3) called the Nutritional Science Initiative (NuSI) to try and build a high-integrity body of studies on the impact of diet on our health. Honest nutritional science studies that aren’t brokered by a food company with an agenda are hard to come by, so I feel optimistic about the work that might come out of NuSI.
** Phinney shared the story of an ultra-marathoner (100-mile races) who needed to burn between 12,000 and 14,000 calories per race, but could only pack his body with several thousand carbohydrate calories before and during the race. Phinney pointed out that the racer – despite having only six percent body fat – had 35,000 calories of fat stored in reserve. By accessing those calories, he was able to close the energy gap created by long periods of exertion. Once that racer trained his body to burn fat instead of carbohydrates, he began setting personal ultra-marathon records.
*** In fairness, the USDA has morphed the food pyramid into a food plate that promotes vegetables and fruits more strongly than the pyramid did. And although it recommends a smaller “share of plate” for grains than it once did, it doesn’t explicitly address target macronutrient ratios for fats vs. protein vs. carbohydrates.