Research suggests junk food may be as addictive and destructive as drugs, booze and tobacco… and could be a big reason Americans are so obese. Here’s how to tell if you might have a problem, and what to do about it…
After my divorce several years ago, I moved into a new apartment in a secure building in a safe neighborhood. Despite safety precautions, I was afraid to be alone at night.
So rather than sleep, I’d sit up till the wee hours, watching TV and eating – ice cream, cookies, crackers, chips. It didn’t matter.
But what I was eating did matter. New research suggests that food – especially highly processed, calorie-dense treats – may actually be physically and psychologically addicting, and can lead to the same changes in brain activity and behavior that occur with cocaine and heroin.
The result? Americans are nearly 20 pounds heavier, on average, than they were in 1990, and nearly two-thirds of us are overweight or obese, according to a 2011 Gallup poll. Food addiction may partially explain these extra pounds, and why some women just can’t lose weight.
“We tend to look at obesity as a lack of willpower – that if you’d just put down the cheeseburger and go for a run, you’d be fine,” says leading food addiction researcher Paul Kenny, Ph.D., associate professor of molecular therapeutics at the Scripps Research Institute in Jupiter, Fla.
“But it’s [not] that simple,” he says. “There’s a population of overweight people who have problems with highly palatable food, so-called ‘junk food,’ the way others do with gambling or crack cocaine.”
Not every overweight person is a food addict. Nor does every food addict have a weight problem. Many control their weight with excessive exercise, purging, even stimulant use. Food addiction is measured not by body size but behavior.
“Food addicts lose control when they eat because their brains react on a neurochemical level either to their relationship with food – habitually eating when something unpleasant happens – or substances in the food itself,” explains Kimberly Dennis, M.D., medical director of Timberline Knolls, a residential treatment center for eating disorders and addiction in Lemont, Ill.
“It’s very different from the sedentary person who just eats too many chips,” she says.
This Is Your Brain on Junk Food
How can junk food be the culinary equivalent of crack cocaine?
Think about what makes stuffed-crust pizza, French fries, double-fudge ice cream and oversized cinnamon buns irresistible: copious quantities of sugar, salt and fat. These ingredients stoke the brain’s reward center in ways that whole foods, in their natural state, don’t.
“These foods are engineered for you to crave and eat compulsively,” says Ashley Gearhardt, a food addiction researcher and assistant professor of psychology at the University of Michigan.
Compared to, say, a piece of fruit, the sugar in jelly beans is more pure and potent, and it hits your system faster because there’s no fiber and other ingredients to slow it down, she says.
“When you punch up the reward and speed [its absorption by the body], it becomes so powerful it hijacks the [brain’s] reward system,” Gearhardt says.
One key driver of the reward system is the neurotransmitter dopamine, which is released in the brain whenever we experience something pleasurable, like food, sex or drugs. Dopamine is a “reward” that makes us want to do it again.
But here’s the catch: When the reward system gets pinged repeatedly, it gets so overstimulated that it automatically dials back the response.
That triggers a vicious cycle. Because your body doesn’t feel as big a reward – a condition known as tolerance – you consume greater amounts in pursuit of ever-diminishing rewards until, eventually, you get virtually no response.
That classic cycle is well understood for addictive substances such as cocaine. Junk foods can trigger it too, according to 2010 research by Kenny’s team at the Scripps Research Institute, published in Nature Neuroscience.
Kenny fed a group of rats American diet staples like bacon, sausage and cheesecake. Predictably, they got fat. They also became compulsive eaters.
“As the animals became obese, it took more [stimulation] for the animal to experience reward, suggesting the development of obesity is associated with a decrease in the sensitivity and activity of the brain reward systems,” Kenny explains.
The same thing happens in rats that compulsively consume cocaine and heroin, he says.
The reason may be found in the D2 brain receptor, which responds to dopamine, researchers say. Drug addicts and obese people have low levels of D2 receptors; people can be born with genetically low levels as well.
When D2 levels are low, it leads to compulsive eating, according to another experiment by Kenny’s team. When researchers artificially lowered rats’ D2 receptor levels, they still ate normally – until they got junk food. Then they went wild, eating compulsively even when faced with pain.
“The rats with the lower D2 receptors were so motivated to eat, they ignored the negative consequences,” Kenny explains.
The rat study results may apply to people, according to functional magnetic resonance imaging (fMRI) studies on women.
In research Gearhardt led at Yale University, 39 young women filled out the Yale Food Addiction Scale (YFAS), a 25-question assessment modeled after standard tests for drug and alcohol abuse.
Then fMRI scans measured brain activity while the women looked at pictures of milkshakes and glasses of water, and again when they drank either the milkshake or a tasteless solution.
When simply viewing milkshake images, women who scored high for food addiction showed more activity in the parts of the brain’s reward centers associated with craving addictive substances than women with lower scores.
“Seeing food cues gives food addicts a big dopamine burst in the brain, which makes them want food even more,” Gearhardt explains. “Even if they’re resolved to eat better, walking by a fast-food place could trigger the desire to go in and seek out that food.”
“Wanting really seems to be driving the addiction,” she says.
But wanting is only one obstacle food addicts face. Another is losing control once they get started. That’s what sets bona-fide addicts apart from people who just love to eat. Addicts don’t savor their food – they devour it.
“Even when the food isn’t great, they can’t stop eating it,” Gearhardt says.
Blame dopamine again. In healthy eaters, brain levels drop once you’re done. Not so with addicts, says Gearhardt.
“With drug abuse, dopamine stays elevated, so you continue to want more,” she says. “We see the same continuous dopamine spiking when people binge on sugary foods.”
Gearhardt’s fMRI scans showed that once the food addicts drank their milkshakes, they had less activity in the brain region that tells you to stop eating when you’ve had enough.
“It’s like the alcoholic who says, ‘I’m only having one drink,’” Gearhardt says. “With food addicts, the brakes don’t come on – they lose control of their consumption.”
Two factors raise the risk of food addiction substantially, research suggests. One is a family history of addiction (drugs, drink, gambling or pornography). The other is your world and diet are filled with highly processed foods.The latter is almost impossible to avoid in modern life: We’re bombarded with constant cues to eat – from fast-food joints and junk-food TV commercials to the snacks clustered at checkout counters in even non-food stores.
“What we’re seeing now is people vulnerable to this environmental risk factor becoming obese,” Kenny says.
If you think you might be a food addict, here are some red flags:
- You eat certain foods even when you’re not hungry.
- Cutting back on certain foods (other than caffeinated drinks) makes you anxious or agitated.
- Overeating makes you sluggish or tired.
- You often eat before going out with friends so they can’t see how much you eat.
- You’re ashamed or distressed about your eating habits.
- Food and eating issues interfere with your health or daily activities.
- Once you start eating, you have trouble stopping.
- Despite emotional or physical problems related to your eating, you continue to eat the same foods or amount.
- Eating the same amount of food doesn’t make you feel as good as it used to.
How to Recover
As with other substance issues, getting over food addiction may require more than just good intentions.
“People struggling with food consumption really beat themselves up,” Gearhardt says. “But if you’re experiencing the same thing an alcoholic does, expecting to just ‘white-knuckle it’ through a diet probably isn’t going to work.”
These strategies can help break the addiction cycle and get you on the path to weight-loss and recovery, experts say.
Try cognitive behavioral therapy. This psychological technique teaches real-life coping skills for dealing with problems without reaching for food. It also provides strategies that pre-empt overeating, like scheduling regular meals rather than grazing, not keeping trigger foods in the house, and sticking to a grocery-shopping list.
Find a therapist near you through the National Association of Cognitive Behavioral Therapists and the Association for Behavioral and Cognitive Therapies.
“It’s helpful to connect with other people who’ve been where you are and found a way out,” Dr. Dennis says.
Don’t let yourself get hungry. Dieters are often tempted to skip meals – but if you’re a food addict, eating three meals and one or two snacks a day is key.
“Being really hungry sets you up to fail because that primes the dopamine system to be more active,” Gearhardt explains.
Pack snacks. Tuck containers of your own “safe” foods into your bag or car, so you’ll be prepared for a lack of healthful foods or tempting situations – say, if you’re stuck near an airport food court when your flight’s delayed. Eat your own stuff, and you’re less likely to topple off the wagon.
“I never leave home without containers of lean turkey breast or beef jerky, sliced vegetables and fruit – because I never know if I’ll be delayed or the food options I’ll have,” says Stephanie Barthmare, a psychotherapist in the weight management center at Methodist Hospital in Houston.
Skip food ads. Recording shows and watching them later allows you to fast-forward through mouth-watering advertisements so you’re less likely to binge.
Consider residential treatment. If obesity is threatening your health, treatment centers can provide a break from the constant barrage of food cues that tempt you to eat. It’s a pricey option, but insurance may cover some expenses.
“If someone can’t get through the day without multiple binges, spending 30-60 days in a less-triggering residential environment may help them gain some control,” Dr. Dennis says.
Are You Addicted to Food?
There’s nothing wrong with giving in to temptation from time to time. But have you crossed the line from feeding your body to feeding a food addiction? Find out with this food addict quiz.