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Commentary: The pleasure trap: Why we have an obesity problem

By Douglas J. LisleWhen I went out on my front porch recently to pick up the paper, I saw that I had done it again. I had left the porch light on, and once again accidentally committed mass murder.

By Douglas J. LisleWhen I went out on my front porch recently to pick up the paper, I saw that I had done it again. I had left the porch light on, and once again accidentally committed mass murder. The moths had spent all night flying into the porch light, become exhausted, and died. There was a little pile of them there, victims of my mistake. I usually turn the light off before going to bed, to spare their lives.I聮m sure most children ask their parents, at some point, 聯Why do the moths fly into the flame?聰 as this type of behavior is often fatal. As adults, we give the usual answer 聴 聯Because they are attracted to it.聰 Perhaps not that satisfying to a particularly inquisitive child, but it was good enough for me. I would turn 50 years old before this phenomenon was explained to me in any real detail.It turns out that moths are designed to fly toward the moon (or the stars, perhaps), to make use of celestial bodies as a sort of compass point. By flying to the light, they get above the local fray, then from a higher vantage point, sense where there might be mates or food, and then fly toward those enticing targets. Later, they can again fly up toward the light, and using the moon or stars again as a compass, and find their way home (or wherever it is that moths go). This is a valuable instinct. It works great in a natural setting. At night, the brightest object in the sky is the moon. There aren聮t any other big sources of light, so this means that the moon is a reliable guidepost 聴 like a trusted friend that would never let you down. In that setting, flying toward the light is the right thing to do, and no self-respecting moth ever resists this attraction.Nowadays, of course, the moths near me no longer live in a natural setting, being surrounded each evening by a sea of artificial lights. This means that quadrillions of moths will make the same type of fatal mistake every year. They fly to light, and run smack into the little glass enclosure for the bulb. They might not die in from the heat of the 聯flame,聰 but they die because of a relentless internal motivational force driving them to return to the light over and again, no matter how exhausted they are. Even if the moon is full and shining, they hit my porch light repeatedly until they die. Why?It is probably because they are designed to fly toward the brightest light 聴 not just any light. And my porch light is many times brighter than the moon. For the eyes of the moth, there is no contest 聴 its tiny brain insists that the bright porch light is the right target. It is not a normal stimulus. It is what neurobiologists call a supernormal stimulus. And a supernormal stimulus trumps a normal stimulus, every time.And this helps explain a great deal of our modern day problems, struggles and various neuroses. Why is losing weight the No. 1 personal goal of Americans? Because we are so dreadfully overweight, of course. No statistics need to be cited here 聴 just use your eyes. But why are we so dreadfully overweight? Because we eat too much high fat, high sugar and processed food (of course). But if we are aware of the problem (we are) and know what to do to solve it (we do), why does this problem persist?What is going on is what Dr. Alan Goldhamer and I refer to as 聯the pleasure trap.聰 It begins with our natural design. In a natural setting, we were designed to seek out the richest source of calories that we could find. We have a way to do this, so that we don聮t do something stupid like eat lettuce all day long when there is fruit available, instead. Lettuce is maybe 100 calories per pound, and if you have a stomach big enough to eat only three to five pounds of food each day, you won聮t survive long on lettuce. You can聮t survive for long on 300-500 calories a day. Fruit has about three times the calories, at 300 calories per pound. Much more valuable biologically. So how are we smart enough to avoid wasting our time eating lettuce when we could be eating fruit?Well, neuroscientists tell us that there are chemicals in your brain, neurotransmitters, that signal pleasure from eating, and will signal more intensively when foods with greater calorie densities are eaten. Good for the neuroscientists. But I think we already essentially knew this. We eat foods with greater calorie densities because they taste better.But here is where it gets interesting. What if you have a species that is designed to eat things like fruits, vegetables, whole grains and perhaps some occasional lean meat? What if the average calorie density of the diet-of-the-species-design was about 500-600 calories per pound? The diet would be a mixture of foods like lettuce (100 calories per pound), vegetables (about 200), fruits (about 300), whole grains, beans, and potatoes (all about 500聳600 calories per pound). Throw in a few nuts and seeds, and occasional animal food (maybe), and you have a healthy, lean diet of about 500-600 calories per pound on average. And guess what?Not a single member of the species will be fat if it eats its natural diet!After all, how many fat zebras, aardvarks or elephants are ever seen? Wild horses, bison or kangaroo? We don聮t see obese animals in the wild because obesity has been engineered out of their design. By eating the foods of their nature, no animal would systematically overeat. This includes us.But what if you engineered the food to taste better? What if you took foods that were normally 500 calories per pound (like a baked potato) and swathed them in butter (4,000 calories per pound)? What happens next is logical. The food with higher calories per pound will taste better, because better taste is pretty much just a detection mechanism for increased caloric density. So if you make the food taste better, you do this by making the food more calorically concentrated. And it looks like this: potato chips (2,500 calories per pound), chocolate (3,000 calories per pound), oily dressings (4,000 calories per pound), and refined sugar (1,800 calories per pound). Adding fat and sugar to foods makes them taste better, by turning basic food into supernormal-stimuli-food.And now we have the answer to the great motivational dilemma of our time: Why do so many smart, savvy people have such a problem controlling their weight and their health? Answer: They live in a time when their natural design is being subverted. We simply weren聮t designed to be confronted with the supernormal dietary choices that we now have available. We fly again and again into the 聯light,聰 and it steals our collective health, vitality, and beauty. Wow.Fortunately, we aren聮t quite moths, and we can learn to outwit this trap. With a copy of a good book (see McDougall聮s The Starch Solution), you can soon be on your way. Sure it takes effort, but then so does running to the doctor, worrying about your health, and lugging around an unwanted waistline. With some simple changes, you can change your life.聴 Douglas J. Lisle is the psychologist for The McDonald Wellness Program. He is the co-author of The Pleasure Trap: Mastering the Hidden Force That Undermines Health and Happiness. He wrote this for The Free Lance-Star in Fredericksburg, Virginia.