Synopsis
The body's built-in reward system, driven by the chemical dopamine, is a fascinating adaptation: It tells us to do more of the things that give us pleasure. Creative energy, falling in love, entrepreneurship, and even the continued propagation of the human race are driven by this system...just as is, unfortunately, the urge to overeat. In "The Fix", Dr. Pamela Peeke uses the latest neuroscience to explain how unhealthy food and behavioural "hooks" have gotten us ensnared; indeed, she shows that dopamine rushes in the body work exactly the same way with food as with cocaine. Luckily, we are all capable of rewiring, and the very same dopamine-driven system can be used to reward us for healthful, exciting, and fulfilling activities. "The Fix" makes this possible by laying out a lifelong, 3-stage plan that starts with a 3- to 4-week jump start to break so-called heinous hooks and replace them with healthier actions. Fitness guides, meal plans, and recipes are constructed to bolster the growth of new neurons and stimulate the body's reward system. Gradually, healthy hooks like playing games, meditating, having sex, going for a run, laughing, and learning a new language will replace the junk food, couch time, and other bad habits that leave us unhappy and overweight.
Extrait
CHAPTER 1
The Dopamine Made Me Do It!
THERE IS NOTHING BETTER THAN A FRIEND, UNLESS IT IS A FRIEND WITH CHOCOLATE.
--ANONYMOUS
WE ALL HAVE ONE.
At least one.
A little darling. A best friend. A helper, a life raft.
An entrenched habit that's so comfortable, it feels like a hug or an island of calm.
A fix.
A fix starts simply enough. You think about doing something that you like to do--drink a mojito, or check your iPhone, or get it on with your boyfriend or girlfriend--and that thought lights up an entire dopamine- driven reward pathway in your brain.
You feel a rush of pleasure. You start thinking about when and how you are going to do that thing:
Is it happy hour yet?
Can I sneak a peek at my e-mail during this meeting?
Will he or she be around tonight? When are we going to connect?
Your brain becomes consumed by the drive to satisfy that urge. You try, but you just can't get it out of your head. You give in.
And then, as soon as you satisfy the raging hunger, bingo: You feel another rush. Your brain says, "Yeah! This is amazing. Bring it on. I want more."
You need your fix.
Most of the time, this neurological process is a good thing. Nature wants humans to stick around, so she uses this system to reward us for doing things that will ensure our survival--eating food, bonding with loved ones, having sex, making babies. Preferably as often as possible.
As a result, everything we do--from the time we wake up until we collapse into bed--is driven by reward. We're either getting reward in the short term (enjoying an hourlong massage) or in the long term (earning a college degree after studying for 4 years).
The reward can also be to avoid pain. I learned that as a little girl who didn't like to brush her teeth. After suffering through a cavity, I soon learned that my real reward was never seeing that dentist again.
This same reward system drives us to learn, to create, to innovate, to pursue our goals. But as a medical doctor specializing in metabolism and weight management, logging thousands of hours a year to educate the public about behavioral change, I've seen firsthand how the dopamine rush cuts both ways. The tremendous high you get from a run in the park or a hike to the top of a mountain can be powerful enough to change your life. But that healthy high occupies the same pathways, and can easily become confused with, the dopamine hit from a snort of cocaine or a puff of a cigarette. Clearly, not all rewards are created equal--and some can kill you.
In the past few years, I've started to see a growing manifestation of this double-edged sword in my own medical practice. More and more men and women are coming into my office desperate to find an answer to the same questions: Why can't I stop thinking about food? How can a cookie or plate of pasta or bag of chocolates have this kind of hold on me? I feel like a junkie!
As I listen to people's tortured stories of unbearable cravings, yo-yo dieting, weight obsession, and emotion-driven stress eating, I've seen a pattern emerge. Their pleas for help are no longer your standard "Gosh, I'd love to drop 10 £ds before the reunion" fare. Instead, these entreaties have become eerily similar to the cries for help from my patients with hard- core drug or alcohol addictions:
"I just need that sugar fix every afternoon. If I don't get it, I'll go crazy with withdrawal."
"I need a dose of pizza."
"Those Tostitos and dip are like crack to me--once I start, I just can't stop."
I started to realize that in more and more of my patients, these cravings are the result of a reward system gone awry. I had also reviewed the new science that shows the mere anticipation of that food-related dopamine high will cause the reward centers of the brain to light up like Times Square on New Year's Eve--the same as brain scans of cocaine addicts eager for their next fix. It doesn't take much to trigger this cascade of brain chemicals: A casually mentioned word, a picture in a magazine or on TV, or a smell from a bakery is all it takes to awaken the desperate cravings. That same insatiable drive for reward keeps all addicts pressing the dopamine accelerator, overriding their brain's normal "satisfaction" signals.
These dopamine-driven moments of pleasure start to accumulate. With constant practice, they progress to habits, carving deep neural pathways in the brain. With every repetition of the cycle, those pathways get stronger and healthier alternatives get pruned out to make way for these new, ultra- rewarding but unhealthy habits. A walk in the neighborhood with your best friend begins to pale in comparison with sitting in front of the TV and bingeing on bags of your favorite chips. This False Fix becomes the default, setting up a domino effect, constantly reinforcing itself.
I Need a Fix
Voices of Addiction1
On my blog on WebMD, I asked people to share their thoughts on food addiction--is it real? The answers were very telling. See if you can recognize yourself in any of these comments.
My addiction to ice cream and other sweets began in childhood. Celebrations were made with half pints of the hand-packed ice cream of our choice, which became an addiction to relieve grief, stress, and other emotions. Because after all--life is good with ice cream.
While I have been eating mostly healthy for 9 years, I still cannot have ice-cream-type things in my home--still a binge-type food. Why having it available sets me off, I have no idea.--Jis4Judy
For those whose recommendations include, "Well, just don't eat that," I wish it were that simple. It's like a smoker's need for cigs and an alcoholic's need for alcohol. If I have a lot of sweets available, I have a hard time not eating all of them. I keep it out of the house, except on special occasions.--nursingbug
I still struggle with the bread issue but am constantly re-focusing to look at what I really want: consistency, a comfortable weight, and peace of mind. When I eat binge foods, I switch into an addict, focused on the next fix. I hate that cycle, but not always enough to avoid it.--init4life
Of all the stresses I have subjected myself to in my life, I thought smoking was the worst. I never even thought I had an addiction to food!
When it was clear to me that I was as dependent on food as I was on smoking to get me through events, that's when I realized I was fighting one of the toughest enemies of all ... me.--mawsings
My mother was an alcoholic. She did not eat much; she always felt she was competing for my father's attention, that she had to be thin. So she smoked and drank vodka. She hid the smoking from my father, and she would sneak her vodka on some occasions.
I was hiding foods because I was embarrassed by the size that I had become. Someone asked me why I just didn't stop eating the foods that I was gorging on. I could not do it at that time. I was not ready to change, and I had not hit my rock bottom.--GoingForGoal
See if this sounds familiar: Eat in bed, stay up too late, get rotten sleep. Feel like hell in the morning, reach for sugary, caffeinated foods to stay awake. Mindlessly seek the numbing of "just one more [candy/ chip/cookie]." A glass of wine at dinner becomes three, and maybe even take a sleeping pill before bed to get "a good night's rest."
Without fully realizing it, many people have created a life of continuous, comfortable opportunities to "dope up" in front of the computer, in the doorway of the fridge, and on the couch. They are driven to repeatedly score hits of what I call "False Fixes"--anything (like food) that leads to short-term reward in association with self-destructive behavior, followed by feelings of guilt, shame, and defeat. In contrast, Healthy Fixes are productive, positive habits associated with feelings of pride, happiness, and achievement: the enjoyment of tasty, delicious whole foods, gardening on a sunny day, or taking a long walk with your best friend. When False Fixes prevail, Healthy Fixes are tossed aside. The seductive lies of the False Fixes now occupy center stage. In pursuit of each False Fix, you create self-defeating habits to support your habit. You start to set up rituals surrounding your bingeing. And voila, you're ensnared in your own endless vicious False Fix-seeking cycle.
This phenomenon clearly isn't just in my practice. We can see ample evidence of what many False Fixes have created in society:
Right this second, 800,000 people are texting or chatting on cell phones while driving.
The average child spends 53 hours a week in front of some kind of screen.
The average American family carries almost $15,000 in credit card debt.
And now we see the emergence of food addiction, which is striking us at all ages: Toddlers' obesity rates have doubled in the past 30 years, and older kids' rates have tripled. Teens' rates almost quadrupled. Half the population of the United States will be prediabetic or diabetic by 2020--an estimate that, as a devoted public health advocate and policy advisor, frightens me to the core. We've even made up new words--such as diabesity-- to describe what we're becoming. Even men and women of average size who've never been seriously overweight can struggle with food obsessions and addictive behavior. Folks who have dropped weight and kept it off still continue to grapple with how to avoid their "crack." Food addiction does not discriminate--it can afflict people anywhere along their weight- management journey.
The Most Devious Fix of All
You can get high on dopamine in many different ways. Some fixes are productive, like going to the gym or reading the Sunday New York Times. These highs build you up--you come away from them feeling proud, fulfilled, and eager for more. These are Healthy Fixes.
A False Fix, by contrast, is destructive. You feel guilty, ashamed, and disappointed.
This is the last time. Never again. And I mean it.
But once the False Fix cycle is triggered, you feel like you don't have a choice.
Some False Fixes, like drugs, nicotine, and alcohol, are clearly addictive substances. And let's not forget sex and gambling. But food? Is it a federal offense to rip through an entire cheesecake? Will you be hauled off and convicted of a felony fat count?
For years, many of my colleagues refuted the fact that food can be "addictive." Yes, the research said that foods can be habit forming--but just on a behavioral level. There was no proven biological basis to believe otherwise. What people need is willpower! Hey, it's just a cookie, for crying out loud. Control yourself! Discipline!
Addiction researchers have long documented the danger of "real" drugs of abuse. Not only can you die from your meth addiction, this addictive substance directly changes the physical structure of your brain. As drugs hijack the pleasure system and wipe out dopamine receptors, the brain adapts and adjusts, creating a tolerance that demands ever more of its drug to get the same False Fix high. Eventually the addict has to have the substance to simply feel normal. He doesn't just want it; he needs it. He hungers for it.
At that point, all other healthy survival motivations--self-care, family, friends, career, sex, love--are cast aside in favor of scoring the drug. Researchers call this deadly change "motivational toxicity," which, in the case of hard drugs, can run its course pretty quickly: Basically, unless you get clean, you're looking at jail or even death.
Well, some experts would say, unlike heroin, meth, or crack, at least you can't die from OD'ing on Jamocha Almond Fudge--at least not immediately. So food wasn't considered a "real" addiction. It's never been taken seriously. Until now.
In the past couple of years, the entire medical field has started to shift. Researchers have uncovered irrefutable proof that food itself can, even under the strictest definitions, be considered a substance of abuse. Nora Volkow, MD, director of the National Institute of Drug Abuse (NIDA), has committed millions of dollars to studying the relationship between food and addiction.
Dr. Volkow is my hero. She has made it her professional mission to study how certain foods can hijack the brain's reward system. Beginning her odyssey in 2001, Dr. Volkow and her team used PET scans and radioactive chemicals that bind to dopamine receptors.2 Their research revealed that obese people had far fewer dopamine receptors in the brain's striatum, the reward center, and therefore had to eat more to experience the same reward or high as average-weighted individuals.
In 2002, Dr. Volkow delved into the craving or "wanting" question. When people were exposed to their favorite treat foods but were not allowed to eat them, a tidal wave of dopamine surged through the striatum.3 They said they "hungered" for their fixes. Yet they weren't hungry at all. This is exactly what happens in the brain of drug abusers after just watching a video of people using cocaine.
Since these landmark findings, numerous NIDA-funded studies published in gold-standard peer-reviewed journals such as Nature Neuroscience have proved that the brain is forever changed by this food addiction cycle of anticipation and reward. When rats are given free access to the kinds of "highly palatable foods" that we humans are surrounded with all the time-- such as chocolate, cheesecake, bacon, sausage, and other fat and processed food treats--these foods change the structure of the brain the same way that cocaine does. Researchers from Yale University have used functional MRI (fMRI) studies to prove that both lean and obese women who test positive for addictive behavior around food show the exact same pattern of neural activity as a chronic drug abuser: very high levels of anticipation of their drug of choice--in this case, a chocolate milk shake--but very low levels of satisfaction after consuming them.4
The addiction develops like this: Think of a river during a flood. The water charges over the banks, taking down trees and houses along the way. Continued dopamine flooding in the brain works the same way. The pathway between the ventral tegmental and the nucleus accumbens areas of the brain floods with dopamine again and again. The brain think it has "too much" dopamine--so the brain attempts to compensate for this overabundance by battening down the hatches, decreasing the total number of dopamine receptors to lessen the amount of dopamine your brain absorbs. This "down regulation" decimates receptors in a variety of brain regions, particularly your limbic system, the site of motivation and emotions.
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