We have an uncanny ability to detect subtle distinctions in the caloric density of foods, but only within the natural range.
The traditional medical view on obesity, as summarized Nearly a century ago, a popular saying went: “All obese people are alike in one fundamental respect: they literally overeat.” While this may be true in a technical sense, it refers to overeating calories, not food. Our primitive impulse to overeat is selective. People don’t tend to crave lettuce. We have an innate, natural preference for sweet, starchy, or fatty foods because that’s where the calories are concentrated.
Think about the efficiency of hunting and gathering. We used to have to work hard to get food. In prehistoric times, it made no sense to spend all day gathering types of food that, on average, do not provide at least the necessary calories for a day. It would have been better to stay in the cave. evolved crave foods with the most calories for your money.
If you could do it consistently forage If we ate a kilo of food per hour and it had 250 calories per kilo, it might take us ten hours to recover the day’s calories. But if we picked something with 500 calories per kilo, we could finish in five hours and spend the next five working on the cave paintings. So the higher the energy density (i.e., more calories per kilo), the more efficient the foraging. We developed a keen ability to discriminate foods based on caloric density and to instinctively crave the densest ones.
If you study the fruit and vegetable preferences of four-year-old children, what they like correlates with caloric density. As you can see in the graph below and at minute 1:52 of my video Friday Favorites: Cut out processed and high-calorie foodsthey prefer Bananas instead of berries and carrots instead of cucumbers. Isn’t that just a preference for sweets? No, they also prefer potatoes to peaches and green beans to melon, just like monkeys. prefer Avocados instead of bananas. We seem to have an innate drive to maximize calories per bite.
All the foods that researchers Tried In the study of four-year-olds, naturally, there were fewer than 500 calories per pound. (Bananas topped the chart at about 400.) A funny thing happens when you start to go beyond that: lose Our ability to differentiate. In the natural range of caloric densities, we have an uncanny aptitude for discerning subtle distinctions. However, once we start eating bacon, cheese, and chocolate, which can run into the thousands of calories per pound, our perceptions become relatively impervious to the differences. No wonder, since these foods were unknown to our prehistoric brains. It’s like the dodo bird that didn’t develop a fear response because it had no natural predators (and we all know how that ended) or baby sea turtles that crawl in the wrong direction toward artificial light instead of toward the moon. It’s aberrant behavior that’s explained by an “evolutionary mismatch.”
The food industry exploits our innate biological vulnerabilities by stripping crops of almost pure calories: pure sugar, oil (which is virtually pure fat), and white flour (which is mostly refined starch). It also removes fiber, because fiber has effectively zero calories. If you run brown rice through a mill to make white rice, you lose about two-thirds of the fiber. If you turn whole wheat flour into white flour, you lose 75 percent. Or you can run crops through animals (to make meat, dairy, and eggs) and remove all the fiber. 100 percent of the fiber. What remains is CRAP (acronym for CRAP) used by one of my favorite dietitians, Jeff Novick, for processed, high-calorie foods.
Calories are condensed In the same way that plants become addictive Drugs like opiates and cocaine: “distillation, crystallization, concentration, and extraction.” They even seem to activate the same reward pathways in the brain. Put people with “food addiction” in an MRI scanner and show them a picture of a chocolate milkshake and the areas that light up in their brains (as you can see below and at 4:15 in my video). video) are The same as when cocaine addicts are shown A video of smoking crack. (See images below and at minute 4:18 of my video) video.)
“Food addiction” is a misnomer. People don’t suffer from uncontrolled eating behaviors related to food in general. We don’t typically crave carrots. Milkshakes are packed with sugar and fat, two of the signals our brains receive about caloric density. When people are addicted to food, they are not eating right away. asked When evaluating the various foods based on cravings and loss of control, most of them were considered junk: highly processed foods like doughnuts, along with cheese and meat. The least linked to problematic eating behaviors? Fruits and vegetables. Calorie density may be why people don’t wake up in the middle of the night and binge on broccoli.
Animals do not tend to get fat when they eat the foods they were designed for. There is a confirmed A report of a group of free-living primates becoming obese, but this was a troop of baboons that stumbled upon a tourist lodge’s garbage dump. The garbage-eating animals weighed 50 percent more than their free-ranging counterparts. Sadly, we too can suffer the same unequal fate and become obese from eating garbage. For millions of years, before we learned to hunt, our biology evolved It is largely based on “leaves, roots, fruits and nuts.” Perhaps it would be helpful to go back to our roots and remove the junk.
A key idea I want to highlight here is the concept of animal products as the ultimate processed food. Basically, all nutrients grow from the earth: seeds, sunlight, and soil. That’s where all our vitamins, all our minerals, all the proteins, all the essential amino acids come from. The only reason there are essential amino acids in a steak is because the cow ate them all from plants. Those amino acids are essential—no animal can make them, including us. We have to eat plants to get them. But we can forego the middle ground and get nutrition directly from the Earth, and in doing so, get all the phytonutrients and fiber that are lost when plants are processed through animals. Even ultra-processed junk food may have a little fiber left, but it’s all lost when plants are ultra-processed through animals.
That being said, there was also a big jump in what we would traditionally consider processed foods, and that’s the video we’re heading to next: The role of processed foods in the obesity epidemic.
We are moving forward with a series on the cause of the obesity epidemic. So far, we have looked at exercise (The role of diet versus exercise in the obesity epidemic) and genes (The role of genes in the obesity epidemic and The thrifty gene theory: survival of the fattest), but what really matters is the food.
If you’re familiar with my work, you’ll know that I recommend eating a variety of whole plant foods, as close to what nature intended as possible. I capture this in my Daily Dozen, which you can download for free here or download the free app (iTunes and Android). In the app, you’ll see that there’s also an option for those looking to lose weight: my 21 checklists. But before you go ticking them off, be sure to read about the science behind the checklist in my book How not to dietGet it for free at your local public library. If you decide to purchase a copy, please note that all proceeds from all my books go to charity.