I just finished reading The Pleasure Trap by Drs. Doug Lisle and Alan Goldhamer. This is a fascinating book about factors that affect our eating behavior and the health effects of our diets, both psychological, neurological, biological, environmental, and evolutionary. The authors explain complex topics well, and sprinkle in fascinating examples and historical references to keep it entertaining. Dr. Lisle is a clinical psychologist and Dr. Goldhamer both a Chiropractor and Osteopathic Doctor. They work together at TrueNorth Health Center in Santa Rosa, California. I learned about them though Chef AJ, who considers them to be mentors.
The main idea of the book is that all species, including humans, have a “motivational triad” described below which drives our behavior. This formed as we were evolving, and works superbly in our natural environments. Unfortunately, unnatural factors can short-circuit this mechanism, and make us fall into “the Pleasure trap”. This has severe consequences to our health and longevity. An obvious example is cocaine, which seizes control of the pleasure centers of our brains. But, more importantly to the topic of nutrition, various unnatural foods have “drug-like” effects. Strong evidence is given for this. A couple of caveats before I get to the details:
- The book emphasizes a whole-food plant-based (WFPB) diet, with no animal products, as our natural diet. The authors do admit that while it was evolving our species ate some meat, but argue that the lean game or fish consumed in the ancestral diet bears little relation to meat from modern industrial sources, so modern meat is unnatural for us (a point I made in a previous post). You may think “why can’t we eat healthier versions of modern meat, from lean animals raised in a more natural environment,, fed their natural food?” But the main points of the book are still valid even if you’re skeptical that we need to eat no animal products. Some leaner meats are also less than 700 calories per pound, an important point because part of the authors’ reasoning is that too high caloric density is part of what is unnatural in our modern diets. I think it’s important not to get stuck on this controversial point because the evidence and reasoning about the pleasure trap and its effects are well worth hearing. They remain valid if you use a looser definition of our natural diet that include some not-too-calorie dense animal products, more analogous to those from a natural environment, like say pasture-raised meat or wild fish from a clean source.
- The authors are enthusiastic proponents of medically supervised water fasting. That is a big part of the contribution of their TrueNorth center. They give compelling arguments and scientific evidence of its health benefits. Still, some may find this too extreme. You don’t have to believe in, or want to try, water fasting, to get the benefit of the main part of the book. It is only discussed at the very end of the book. I will go over the evidence about water fasting at the end of this post.
The Pleasure Trap
The first thing explained in the book is the motivational triad: all species are designed to
- seek pleasure
- avoid pain
- minimize energy consumption
You may see right away where this might be going. Fruit is pleasant to eat because it’s nutritious. “Froot Loops” hijack this feedback by making us think an unhealthy food is pleasant. Minimizing energy makes sense if you’ve been working for hours foraging, but not if you’re in an environment that allows you to do very little physical activity. Others have made this argument. But there’s a lot more detail to it in the book.
First, there’s a whole additional layer. Intensely pleasurable experiences, like from eating exquisitely ripe berries or mating, are designed to be occasional rewards. Finding a mate is an end goal. But there is intermediate feedback on the way to keep us on the path, that cause “the moods of happiness”. Further, the actual mechanism for the intermediate feedback is different than the intense pleasure feedback. It involves chemicals like serotonin or endorphins, for example, while intense pleasure involves ones like dopamine.
The fascinating example of a bird, the male desert shrike, illustrates all of these concepts and how superbly it works in the natural environment. But now suppose we introduce something unnatural, like cocaine. This completely short-circuits the mechanism. All the health-promoting intermediate behaviors are skipped, and you jump right to the intense pleasure feedback. It gets worse. The dose needed to get the high keeps increasing. Eventually those caught in the trap care about nothing but the next hit of the unnatural substance. The sad example of lab rats, who are trained to press a lever to get a serving of a drug, is given. They will get hooked and neglect eating, and eventually starve, because they keep pressing the lever. We all know that this can transfer to humans unfortunate enough to be victims of addition. And we know how incredibly hard it is to escape the pleasure trap into which they have fallen.
Next the authors explain that unnatural foods have a drug-like effect. This has gotten steadily worse with the progression of the industrial revolution. First the fiber was stripped from wheat to make white bread, for example. But in this century it has gotten much worse with over-processed manufactured foods. This is relentless, more and more overtaking our modern diet by increased amounts of over-processed foods, and crowding out natural foods, How this happened increasingly in the 20th century and into the 21st was chronicled by Michael Moss in Salt, Sugar, Fat. Now we have food scientists who know how to find the “bliss point”, the perfect combination of substances in food that cause the most hyper-palatability. No wonder they are trigger foods!
And back to the motivational triad, modern society, with the automobile and fast food restaurants, has for the first time in history made it possible for us to be couch potatoes, so we are able to truly maximize pleasure while minimizing effort, which we have a strong evolutionary instinct to do.
Our Exquisitely Tuned Satiety Mechanism
The authors describe in amazing detail our finely tuned elaborate mechanisms for eating just the right amount to stay at the optimum weight for our health. No species, including humans, gets thinner or fatter than is healthy in its natural environment. It’s really hard to summarize and do the details justice, but the mechanisms includes stretch receptors in our stomachs and various hormonal mechanism.to detect fullness. This is related to the “set point” mechanisms you’ve probably heard of. Various elements in our modern diet defeat it, including foods that tend to be much higher in calorie density, outwitting the stretch receptor, or have unnatural substances in them that mess up satiety. And don’t forget the “drug-like” hormonal effects of the trigger foods that lead to the pleasure trap with addictive results or, even for those fortunate to be less sensitive, something close to it.
Taking various foods and separating them into natural foods, with low calorie density, and high nutrient density, vs. unnatural foods with high calorie density and low nutrient density, is where Chef AJs red line came from. I did not explain this well in my previous post on it. These are not being arbitrarily assigned as “good or bad” foods, they are simply foods we evolved to thrive on vs. those that we were not. There are some natural foods to the right of the red line, like avocados, nuts, and seeds. These would have been harder to come by in our ancestors’ natural environment so if we overate them it would only have been occasionally. Also, even for many plant foods, the natural form in our ancestral diet was probably much less calorie dense than modern cultivated forms. These natural foods, (AJs “purple foods”), are likely the only foods to the right of the red line it might be safe to eat “in moderation” (at least for some).
This explains why people have so much trouble eating the modern over-processed diet in moderation. Some of us can get away with it on occasion, while for others it can trigger bingeing. I can get away with it sometimes, but it sure feels like “playing with fire”.
The authors finish up by describing how water fasting has worked out for patients at their center. It has been shown for example, to reverse high blood pressure in a matter of weeks. And there is the added benefit that after you come off from the fast, your taste buds have reset themselves so more natural foods taste good. They emphasize that water fasting needs to be medically supervised or it can be hazardous.