The science of overeating: The good, the bad, and the ugly

I’ve been writing about the emotional journey of my weight-loss project, but obviously there’s more to weight loss than emotions.

There’s also science.

I recently found a book that does a great job explaining the science of overeating, and today I’d like to share with you some of what I’ve learned from it.

The book is called “The End of Overeating: Taking Control of the Insatiable American Appetite.” It’s by a former US FDA head, David Kessler, MD.

You can get the book on Amazon.com here.

In this post I’ll share some of the quotes from the book that really struck me, and my thoughts about them. But be aware — there’s a lot in this book I won’t be sharing with you. I won’t be sharing his research about how the food industry works to “load and layer” food so you’ll become addicted to it. I won’t be sharing the theory of treatment of “Conditioned Hypereating.” I won’t be sharing many other parts of the book. If you like this blog post, “The End of Overeating” may be worth checking out.

Americans weigh more, and eat more

Did you know that Americans didn’t used to be fat? It’s true. According to Kessler, as early as 40 years ago, weight was generally pretty stable across a person’s adult life. “American adults typically gained a couple of pounds between 20 and 40, then lost of couple of pounds in their 60s and 70s.” That was it.

Things have changed. Kessler points out that, in the 40 years between 1960 and 2000, 20- to 29-year-old American women’s average weight has gone from 128 pounds to 157 pounds. At the same time, American women ages 40-49 went from an average of 142 pounds to an average of 169 pounds. And while he didn’t provide the numbers for men, I feel confident that their increase is just as big if not bigger.

Americans are also eating more:

“By far the largest increase has been in the consumption of fats and oils, with a 63% jump over a thirty-three year period, from per capita annual consumption of about fifty-three pounds to about eighty-six pounds. The use of sugars and sweeteners is also up — by a modest 19% — and in that same period we ate 43% more grains and 7% more meats, eggs, and nuts.”

We eat more, and we weight more.

But…Why? Why is this happening? And what can we do about it?

Introducing the “Hyper-palatable 3″: Sugar, Fat, and Salt

Kessler points out that “Early human diets contained only about 10 percent fat. Sugar intake, primarily from ripe fruit, was also modest.” And I imagine early humans intake of salt was modest, too.

These foods are vital in small quantities, but they were rare, so humans developed the ability and the desire to seek them out. “That may be why we have 300 or more olfactory receptors to sense the odors associated with fats, as well as an innate preference for sweetness,” Kessler says.

So what happens when sugary, fatty and salty foods — once rare and pursued — become available in unlimited quantities?

A study at the University of Chicago performed by scientist Anthony Sclafani provides an answer that probably won’t surprise you. Sclafani fed rats a “supermarket diet:”

“[The rats were fed foods including] sweetened condensed milk, chocolate-chip cookies, salami, cheese, bananas, marshmallows, milk chocolate, and peanut butter. After ten days, animals that were fed the supermarket diet weighed significantly more than rats that were fed bland chow. And the rats on supermarket diets continued to gain weight, eventually becoming twice as heavy as their control counterparts.”

Yikes!

But as I said, you’re probably not surprised by this. Most of us have experienced “losing control” against foods high in sugar, fat, and salt.

That’s why Kessler calls sugary, fatty and salty foods “hyper-palatable.”

They’re not simply “palatable” — that is, “good tasting.” They’re “hyper-palatable” — off-the-scale desirable, tasty beyond anything humans have developed resistance to.

And it turns out that, if you eat a ton hyper-palatable food, it’s not because you have some sort of moral failing.

It’s because of biology.

When we go up against sugary, fatty, and salty foods, our biology can easily be turned against us. Then overeating — and getting fat — wins.

This is your brain on heroin opioids

Kessler says that “alone among the senses, taste is hardwired to brain cells that respond to pleasure.”

That means that there are specific neurons that respond to different aspects of the eating experience. Some specific neurons fire when you eat something sweet. Others respond to a certain texture in food. “A neuron stimulated by a sweet taste that has been coupled with a fatty texture would be activated when we eat, say, an éclair.”

When these neurons fire, they trigger the body’s pleasure system:

“When we first put a highly palatable food in our mouths, taste buds in the tongue respond by sending a signal to an area of the lower brain responsible for controlling many of our involuntary activities, such as breathing and digestion. When the lower brain receives that signal, it activates the neural circuitry that contains natural opioid molecules.”

“From the lower brain, the sensory experience of taste travels through the midbrain, reaching regions where the sensory signals of food are integrated. Those signals are ultimately relayed to the ‘nucleus accumbens,’ an area of the brain that is the center of reward.”

This causes the release of opioids into the brain. Also known as endorphins, they have a “rewarding effect similar to morphine and heroin.”

That gives the big burst of pleasure that is familiar to many of us. It’s what we feel when we eat a hyper-palatable food — in my case for instance, a chocolate-chip cookie. The intense pleasure is the opioids being released into the brain.

A vicious cycle: Opioids drive even more eating

Unfortunately, when you eat hyper-palatable foods — foods that are full of sugar, fat and salt — you don’t generally become satisfied.

In fact, eating hyper-palatable food drives you to eat even more hyper-palatable food:

“In a cyclical process, eating highly palatable food activates the opioid circuits, and activating these circuits increases consumption of highly palatable food.”

“Animals eat more high-sugar, high-fat foods after receiving opioid injections. We also know that after using drugs that stimulate the opioid circuitry, people report that palatable food is more pleasant and they eat more of it.”

Not only do the opioids activated by hyper-palatable food stimulate eating more, they also keep you from growing tired of those foods.

You’re never satisfied. You just keep wanting more.

Sugar, fat and salt literally change your brain

I’m not using “literally” to mean “figuratively,” either. As we’ll see in a moment, the cycle of cue/dopamine/opioid/habit/repeat literally changes the way your brain functions in regard to food.

Cues to eat

First, there are the “cues” to eat.

A “cue” is a stimulus that “trips the trigger” and tells you to eat. It’s what makes you think, “Oh yeah, it’s time to eat that now.”

For me, the cue to eat a cookie might be seeing it at the coffeeshop.

Or I might be unaffected by seeing it, but the smell of it, fresh-baked, might cue me to eat.

The more I obey a cue, the stronger and more far-reaching that cue becomes. After enough times of eating a cookie after I’ve seen it, not only will I get cued by seeing the cookie, I’ll also start being cued by driving by the coffeeshop where the cookie is available. Then I’ll start getting cued every time I get into the car. Then I’ll start getting cued to go buy a cookie when I even think about getting into my car.

Kessler says, “With experience, the association between cues and food becomes even stronger, and we become more single-minded in our focus and our pursuit.”

Not surprisingly, he concludes, “That increases consumption.”

Dopamine and the pursuit

When we see a cue, the chemical dopamine is released in the brain.

This releasing of dopamine is like putting your foot on the gas pedal of desire. It makes you go faster in the pursuit of food.

“If opioids give food its pleasure and help keep us eating, dopamine motivates our behavior and impels us toward food.”

When a person gets cued and dopamine is released, they are driven to overcome whatever obstacles might be between them and the goal.

How hard will dopamine drive us in pursuit of hyper-palatable foods? Scientist Sarah Ward, working at the University of North Carolina at Chapel Hill, found this:

“The breaking point where the animals will no longer work for a sugar and fat ‘reward’ is slightly lower than the breaking point for cocaine. Animals are willing to work almost as hard to get either one.”

That’s some pretty serious pursuit.

And again, it’s not a moral weakness if this is happening to you. It’s not you “just being weak” or “needing to try harder.” It’s your brain’s natural reaction to constant exposure to foods full of sugar, fat, and salt.

Habits nail that coffin shut

If you act out a set of behaviors over and over, it will usually become a habit. And, because of the pleasure that comes with the opioid release of eating hyper-palatable foods, habits of eating sugar, fat, and salt are very easy to form.

As Kessler says,

“A continuous cycle of cue-urge-reward is set in motion and eventually becomes a habit.”

“In one study, people were given high-sugar, high-fat snacks for five consecutive mornings. For days afterward, they wanted something sweet at about the same time each morning that they had been fed the snack, even though they had not previously snacked at that time.”

This is serious, because when you have a habit, you can actually take action before you know you are doing it:

“Researchers have been able to measure movement before subjects know they are going to move. Brain activity stimulates a motor response in advance of awareness.”

Have you ever just “found yourself” eating, before you even knew you were doing it? That’s “action in advance of awareness.” It’s part of the effect that hyper-palatable foods have on your brain.

Summing up the science

Kessler concludes:

“Foods high in sugar, fat and salt are altering the biological circuitry of our brains….Rewarding foods are rewiring our brains. As they do, we become more sensitive to the cues that lead us to anticipate rewarding foods.”

“The cycle: a cue triggers a dopamine-fueled urge…dopamine leads us to food…eating food leads to opioid release…and the production of both dopamine and opioids stimulates further eating.”

Kessler has defined this behavior as “Conditioned Hypereating.” It’s a syndrome in which this new brain chemistry has taken control.

In conditioned hypereating, everything seems to become a cue to eat. The cue releases the dopamine, which drives us to eat, which releases the opioids, which drives us to eat more… And the cycle goes on and on, and we get fatter and fatter.

Thinking in terms of 3 types of food: The good, the bad, and the ugly.

As you may recall from a previous post, I very highly value feeling free to make my own choices. Discovering that I was being a puppet in the hands of sugar, fat, and salt really motivated me to change.

As I’ve contemplated this change, I’ve realized that most people see food in two categories:

1. The good: Food you enjoy. You eat it, because you like it.
2. The bad: Food you don’t enjoy. Generally speaking, you don’t eat it. You avoid it because you don’t like it.

Before hyper-palatable foods were constantly available to us, these two categories worked just fine. But I believe a third category of food has arisen:

3. The ugly: Hyper-palatable food. Hyper-palatable food is food you enjoy — too much. You don’t eat it because

• • it takes control of your biology,
  • it alters your brain chemistry, and
  • it takes control of your behavior and makes you eat even more.

Since I’ve been thinking of food in these three categories, rather than the old two, it’s been much easier for me to change my eating habits.

Now that I know the truth about hyper-palatable foods, I see them for what they really are. If a food is hyper-palatable, I don’t eat it. It doesn’t matter if its tasty. I don’t need the trouble.

I’ve also come to recognize the feeling I get when I eat a hyper-palatable food. When I eat a hyper-palatable food, I feel an intense pleasure, located in the center of my head, along with the desire to eat more of that food. Your signal may be different from mine, and I encourage you to discover what your signal is.

For me, if I feel that “hyper-palatable pulse,” I stop eating that food right away, because I know it will take control of me if I give it the chance.

The bigger picture

I have some other ideas about the importance of managing your brain chemistry that I’ll discuss in future posts. Today, I’ll simply say that I suspect that there is a kind of brain chemistry that feeds the feeling of deep blessing. I believe that such brain chemistry is actually incompatible with the driven-to-eat brain chemistry that comes from eating hyper-palatable foods.

My suspicion is that you can either be in the “blessed” state of mind, or the “pursue hyper-palatable foods” state of mind — but not both. And because we all want to live from a flow of deep blessing, knowing how to get your brain chemistry right is important.

Put another way, I’m suspecting that the act of making changes in our diet runs down to the core of who we are as people, and directly into our spiritual lives. It’s not just about losing weight. It’s about where we get our sense of sustenance, on the deepest levels.

And that’s a good thing, because I know that I’m not seeking a way to lose weight if it means spending the rest of my life in a battle to keep from getting fat again. If you’re like me, you’re not interested in a life-long battle, either.  So whatever solution I arrive at has to not only work in the long-term, it has to really, truly help me feel like I’m being fed by a deeper blessing current. I think most other people would like that, too.

I’ll talk more about it in coming posts, but I wanted to give you a sense of where I think all this is going.

For now, I suggest you start to think in terms of foods you like to eat (the good), foods you don’t like to eat (the bad), and hyper-palatable foods that cause you pleasure, but which you don’t eat anymore (the ugly).

I welcome your thoughts in the comments.

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