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你可能喜欢What Happens to Your Brain When You Eat Junk Food (And Why We Crave It)&|&James Clear
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Featuring fresh takes and real-time analysis from HuffPost's signature lineup of contributors
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What Happens to Your Brain When You Eat Junk Food (And Why We Crave It)
Most of us know that junk food is unhealthy. We know that poor nutrition is related to heart problems, high blood pressure, and a host of other health ailments. You might even know that studies show that eating junk food has been linked to .But if it's so bad for us, why do we keep doing it? There is an answer. And the science behind it will surprise you.Why We Crave Junk FoodSteven Witherly is a food scientist who has spent the last 20 years studying what makes certain foods more addictive (and tasty) than others. Much of the science that follows is from his excellent report, According to Witherly, when you eat tasty food, there are two factors that make the experience pleasurable. First, there is the sensation of eating the food. This includes what it tastes like (salty, sweet, umami, etc.), what it smells like, and how it feels in your mouth. This last quality -- known as "orosensation" -- can be particularly important. Food companies will spend millions of dollars to discover the most satisfying level of crunch in a potato chip. Their scientists will test for the perfect amount of fizzle in a soda. These factors all combine to create the sensation that your brain associates with a particular food or drink.The second factor is the actual macronutrient makeup of the food -- the blend of proteins, fats, and carbohydrates that it contains. In the case of junk food, food manufacturers are looking for a perfect combination of salt, sugar, and fat that excites your brain and gets you coming back for more.Here's how they do it...How Science Creates CravingsThere are a range of factors that scientists and food manufacturers use to make food more addictive.Dynamic contrast. Dynamic contrast refers to a combination of different sensations in the same food. In the words of Witherly, foods with dynamic contrast have:... an edible shell that goes crunch followed by something soft or creamy and full of taste-active compounds. This rule applies to a variety of our favorite food structures -- the caramelized top of a creme brulee, a slice of pizza, or an Oreo cookie -- the brain finds crunching through something like this very novel and thrilling.Salivary response. Salivation is part of the experience of eating food, and the more that a food causes you to salivate, the more it will swim throughout your mouth and cover your taste buds. For example, emulsified foods like butter, chocolate, salad dressing, ice cream, and mayonnaise promote a salivary response that helps to lather your taste buds with goodness. This is one reason why many people enjoy foods that have sauces or glazes on them. The result is that foods that promote salivation do a happy little tap dance on your brain and taste better than ones that don't.Rapid food meltdown and vanishing caloric density. Foods that rapidly vanish or "melt in your mouth" signal to your brain that you're not eating as much as you actually are. In other words, these foods literally tell your brain that you're not full, even though you're eating a lot of calories.The result: You tend to overeat. In his best-selling book , author Michael Moss describes a conversation with Witherly that explains vanishing caloric density perfectly...I brought him two shopping bags filled with a variety of chips to taste. He zeroed right in on the Cheetos. "This," Witherly said, "is one of the most marvelously constructed foods on the planet, in terms of pure pleasure." He ticked off a dozen attributes of the Cheetos that make the brain say more. But the one he focused on most was the puff's uncanny ability to melt in the mouth. "It's called vanishing caloric density," Witherly said. "If something melts down quickly, your brain thinks that there's no calories in it ... you can just keep eating it forever." Sensory specific response. Your brain likes variety. When it comes to food, if you experience the same taste over and over again, then you start to get less pleasure from it. In other words, the sensitivity of that specific sensor will decrease over time. This can happen in just minutes.Junk foods, however, are designed to avoid this sensory specific response. They provide enough taste to be interesting (your brain doesn't get tired of eating them), but it's not so stimulating that your sensory response is dulled. This is why you can swallow an entire bag of potato chips and still be ready to eat another. To your brain, the crunch and sensation of eating Doritos is novel and interesting every time.Calorie density. Junk foods are designed to convince your brain that it is getting nutrition, but to not fill you up. Receptors in your mouth and stomach tell your brain about the mixture of proteins, fats, carbohydrates in a particular food, and how filling that food is for your body. Junk food provides just enough calories that your brain says, "Yes, this will give you some energy," but not so many calories that you think, "That's enough, I'm full." The result is that you crave the food to begin with, but it takes quite some time to feel full from it.Memories of past eating experiences. This is where the psychobiology of junk food really works against you. When you eat something tasty (say, a bag of potato chips), your brain registers that feeling. The next time you see that food, smell that food, or even read about that food, your brain starts to trigger the memories and responses that came when you ate it. These memories can actually cause physical responses like salivation and create the "mouth-watering" craving that you get when thinking about your favorite foods.All of this brings us to the most important question of all.Food companies are spending millions of dollars to design foods with addictive sensations. What can you and I do about it? Is there any way to counteract the money, the science, and the advertising behind the junk food industry?How to Kick the Junk Food Habit and Eat HealthyThe good news is that the research shows that the less junk food you eat, the less you crave it. My own experiences have mirrored this. As I've slowly begun to eat healthier, I've noticed myself wanting pizza and candy and ice cream less and less. Some people refer to this transition period as "gene reprogramming." Whatever you want to call it, the lesson is the same: If you can find ways to gradually eat healthier, you'll start to experience the cravings of junk food less and less. I've never claimed to have all the answers (or any, really), but here are three strategies that might help.1. Use the "outer ring" strategy and the "5 ingredient rule" to buy healthier food.The best course of action is to avoid buying processed and packaged foods. If you don't own it, you can't eat it. Furthermore, if you don't think about it, you can't be lured by it.We've talked about the power of junk food to pull you in and how memories of tasty food in the past can cause you to crave more of it in the future. Obviously, you can't prevent yourself from ever thinking about junk food, but there are ways to reduce your cravings. First, you can use my
to avoid processed and packaged foods at the grocery store. If you limit yourself to purchasing foods that are on the outer ring of the store, then you will generally buy whole foods (fruits, vegetables, meat, eggs, etc.). Not everything on the outer ring is healthy, but you will avoid a lot of unhealthy foods.You can also follow the "5 ingredient rule" when buying foods at the store. If something has more than 5 ingredients in it, don't buy it. Odds are, it has been designed to fool you into eating more of it. Avoid those products and stick with the more natural options.2. Eat a variety of foods.As we covered earlier, the brain craves novelty. While you may not be able to replicate the crunchy/creamy contrast of an Oreo, you can vary your diet enough to keep things interesting. For example, you could dip a carrot (crunchy) in some hummus (creamy) and get a novel sensation. Similarly, finding ways to add new spices and flavors to your dishes can make eating healthy foods a more desirable experience.Moral of the story: Eating healthy doesn't have to be bland. Mix up your foods to get different sensations and you may find it easier than eating the same foods over and over again. (At some point, however, you may have to .)3. Find a better way to deal with your stress.There's a reason why many people eat as a way to cope with stress. Stress causes certain regions of the brain to release chemicals (specifically, opiates and neuropeptide Y). These chemicals can trigger mechanisms that are similar to the cravings you get from fat and sugar. In other words, when you get stressed, your brain feels the addictive call of fat and sugar and you're pulled back to junk food.We all have stressful situations that arise in our lives. Learning to deal with stress in a different way can help you overcome the addictive pull of junk food. This could include
or a . Or something more physical like
or . With that said, if you're looking for a better written and more detailed analysis of the science of junk food, I recommend reading the #1 New York Times best-seller .Where to Go From HereOne of my goals with this article is to reveal just how complex poor eating habits can be. Junk food is designed to keep you coming back for more. Telling people that they "need more willpower" or should "just stop eating crap" is short-sighted at best.Understanding the science behind junk food is an important first step, but I don't want you to stop there. I wrote a free 46-page guide called , which explains strategies for winning the battle against junk food and improving your eating habits. You can download it .James Clear writes at , where he shares ideas about using behavior science to improve your performance and master your habits. For useful ideas on how to live a healthy life, both mentally and physically, .
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Thanks for your report!Your Secrets to Healthy Snacking
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Your Secrets to Healthy Snacking
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Everyone knows that some foods are better snacking choices than others. What's not so easy in real life is putting all the stuff we know about healthy snacking into practice. In other words, it's tough to balance those "oops, I know I should only have a little bit of this but I just ate the whole bag" munchies with the healthy foods we know we should be eating.
We decided to ask our readers how they make healthy choices and avoid out-of-control snacking. More than 1,000 13- to 18-year-olds took our online snacking survey and told us how they manage to snack in a healthy way, even when it's hard to do. Here are their tips.
Knowing What to Eat
More than two thirds of the survey-takers said that when they choose a snack they think about how healthy it is (or isn't). That's impressive. Awareness of what's good for you and thinking about your choices are the first steps in making healthy snacking choices.
Plenty of our respondents are doing more than just thinking about healthy snacking choices, though & they're making them, too. More than a third said the snacks they choose most often are health-conscious ones (such as whole-grain crackers, yogurt, fruits, and veggies).
But many who said they think about what they're choosing still find it's not always possible to eat the healthiest snack. That's understandable. Unfortunately, it can be all too easy to give in to a craving or to eat what's easiest to get your hands on when you're really hungry.
Some of our readers said that planning ahead and making sure they have the right stuff on hand can help them make healthy choices when their snacking willpower is low.
Sally, 16, says, "Stocking your fridge with healthy foods will help you get to or stay at a healthy weight. Pigging out on healthy foods feels a lot better than pigging out on cake or another food that is supposed to be eaten in moderation."
Rosie, 14, offers this advice: "Instead of eating unhealthy foods because it's convenient, plan ahead and prepare tasty, healthy foods."
Alena, 16, agrees. "If you have food with you and plan when you will eat, you don't get as hungry and aren't tempted to resort to convenience food from vending machines or fast food."
For many of you, managing your munchies may come down to managing your parents: "A lot of parents buy their kids bad food," says Stephanie, 13. "Ask them to get some healthy food you will enjoy just as much."
Knowing How to Eat
Some of these successful snackers make it sound easy. But it's not always a piece of cake (ha-ha!) to snack well. Most of our survey-takers fessed up and revealed that the types of snacks they like most often are sweet or salty junk foods (such as cookies, ice cream, candy or chips, popcorn, and pretzels).
So how do you begin to snack smarter when there's so much temptation out there?
Many readers talk about giving in - but in moderation. Karni, 14, says, "It's OK to eat unhealthy snacks once in a while, but make sure you balance and eat healthy snacks too."
Lots of people agree with Karni that it's important to treat yourself to the fun stuff - as long as you don't overdo it. And they're right. Thinking of foods as "bad" or "off limits" can even lead to eating problems. Everyone deserves to indulge occasionally.
Angelica, 16, says, "Eat healthy. But from time to time, give yourself something less healthy that you really like. If you deny yourself everything that doesn't meet a healthy standard, you won't be happy, and one day you're going to come home and pig out."
George, 13, offers this idea: "Eat healthy Monday to Friday, then on the weekends you can eat treats."
Lindsay, 14, offers a work-for-your-snacks approach. "Only take one at a time, that way you have to walk over to get another one every time."
Tia, 13, thinks about how her food choices relate to her fitness and performance. "I don't eat that much junk food because I play sports. Junk food just makes me hungry and gain more weight."
When it comes to smart snacking, thinking about how much you're eating as well as what you're eating is wise. More than half of the people in our survey (57%) said they think about the amount they're eating when they snack.
Many of you also know that people tend to eat less if they really focus on what they're eating. As Hannah, 13, says, "Slow down! Enjoy the food that you are consuming!"
Good advice! So appreciate every bite. Focus on taste, texture, and temperature. Notice how spicy a food is. Or how fruity it tastes. That way you'll really enjoy how smooth (or crunchy), how tangy (or naturally sweet), or how refreshingly cold (or soothingly warm) the food you're eating is. And when you slow down you'll also notice when you start to feel full.
Bryan, 14, advises, "Before you eat, ask yourself, 'Am I really hungry?' Don't eat directly out of the bag/box. Pour some of your snack into a bowl (or put it on a plate) and put the bag/box away. Eat the snack out of the bowl instead of out of the bag. This will help limit the amount you eat."Knowing Why You Eat
Like lots of readers, Bryan recognizes that people eat for reasons other than hunger. Knowing why you're snacking & because you're bored, for example, or because you've skipped a meal and let yourself get way too hungry & can help to rein in overeating.
Is It Hunger & or Something Else?
About half of the people who took our survey told us they usually snack because they're hungry, which is great. But the other half said they snack for emotional reasons, like boredom, stress, or anger (42%), or because they're hanging out with snackaholic friends (4%).
Kara, 13, says she eats because "I'm bored and everyone else is eating."
Most of you realize that eating for emotional reasons isn't a great idea. "Snacking because of boredom is a good way to add some bad pounds, so be careful what you eat, when you eat, and why you eat it," says Naomi, 13.
Krystin, 13, says, "Don't eat out of boredom or stress. I eat because of stress sometimes and I am fat for my age."
Claire, 13, says, "The most important thing to do is not just eat out of boredom. If you are bored, go outside and do something!"
Getting variety in your diet is one way to avoid overeating. As Isadora, 14, says, "Be creative, it keeps you from being bored."
Becky, 15, offers this advice: "Learn to think of food as fuel, not comfort."Are You Too Hungry?
Just about all of our survey takers said they snack after school & either when they get home (77%) or before their after-school activities like practice, games, or lessons (22%).
After-school snacks are a good idea, especially if you had an early lunch or dinner is hours away. If you choose right, snacks can help you focus on your homework & not your grumbling tummy. But if you come home from school so ravenous that you reach for the first thing in sight, that can be a problem.
People who skip meals or wait until they're too hungry often eat more than they actually need to satisfy their hunger. And this can lead to weight gain. Healthy snacking between meals can come in handy as a way to manage hunger before it gets totally out of control.
Tia says she snacks when she's "not that hungry but hungry enough to eat something little."
Austin, 14, says, "Eat smaller meals throughout the day, then you don't binge eat all at once."
What's the best way to manage hunger? Having three meals a day and a snack (if needed) at regular set times, such as after school.
Are You Multitasking?
Blair, 14, says that snacking "gives me something to do with homework." Unfortunately, eating at the same time as doing something else is a bad idea. As with any kind of multitasking (doing more than one thing at a time), you're not really focused on your food. And that can lead people to eat way more than they intended.
Emily, 16, says, "Do NOT eat in front of the TV. And try to limit your overall TV watching."
"Television usually makes kids hungry," says Krystal, 13.
What about when you're hanging out with friends? Heather, 14, says, "If I do snack when I'm out with friends, I try to follow the two limit rule, like only taking two bites, or taking only two cookies, so that I'm not eating when I'm not hungry."Your Choice? An Apple a Day!
So what are our survey-takers' healthy faves? When it's time to pick something healthy to snack on, the apple came out a hands-down favorite. Even those who don't see themselves as healthy snackers can deal with apples & like Wesley, 13, who admits, "I don't eat too many healthy snacks (blush!). But when I do select something healthy I usually pick an apple or a yogurt."
Marshelle, 13, wrote that her favorite snack is "apples with a little bit of peanut butter on them."
This snack turns out to be a favorite for many of you. And people who choose apples with peanut butter get a round of applause from nutrition experts. Not only do these two foods offer some great nutritional benefits, but combining proteins (like peanut butter) with carbohydrates (like fruit) offers more staying power. That's because protein can keep you energized long after the carbs are used up.
Shaaziya, 14, chooses "fruit, yogurt, and cereal," which is another great way to balance protein and carbs.
Rafael, 13, says, "I usually choose a banana or a green apple. Sometimes I eat an orange. I'm not into vegetables that much."
Many of you do like vegetables, though. Cut-up vegetables like carrots, celery, broccoli, and cauliflower were a popular snack when drizzled with low-fat dressing or paired with low-fat dip. Vegetables even satisfy Matthew, 15, who admits that for him, "Eating vegetables is not fun. Sometimes they can be gross. However, selecting a favorite topping and dip really puts flavor into the vegetable and satisfies hunger."
Snacking on fruits and vegetables is a great way to make sure you get the
that you're supposed to.
Many of the people who took our survey said they enjoyed smoothies, cereal, granola bars, protein bars, and nuts. These foods can all be healthy choices. But if you're snacking on them, be careful. Foods like cereal, granola bars, or energy bars can be loaded with fat or sugar. Check the label for information to see how much you can realistically eat. And if you're making your own smoothies, choose low-fat milk and hold the sugar & if you add fruit, it'll be naturally sweet.Enjoy It!
Perhaps these snacking ideas give you some inspiration on new things to try. Go ahead and experiment. You may discover new likes & along with some definite dislikes. Courtney, 13, tried a little extreme experimentation and sent us this advice: "Never eat pickles and milk. Yuck!"
Jared, 16, sums it all up nicely. "If you want to stay healthy, just stay smart! Know what to eat and when you should eat & for example, what nutrients you need each day. This is a lifelong process. Start learning."
Reviewed by:
Date reviewed: October 2011 •
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