Healthy eating. It's something everyone knows they should do, but few of us do as consistently as we would like. The purpose of this guide is to share practical strategies for how to eat healthy and break down the science of why we often fail to do so.
Now, I don't claim to have a perfect diet, but my research and writing on behavioral psychology and habit formation has helped me develop a few simple strategies for building and strengthening a healthy eating habit without much effort or thought.
You can click the links below to jump to a particular section or simply scroll down to read everything. At the end of this page, you’ll find a complete list of all the articles I have written on healthy eating.
I. The Science of Healthy Eating
II. How to Make Healthy Eating Easier
- The Importance of Environment for Healthy Eating
- How to Eat Healthy Without Noticing
- What Should I Eat?
- Two Simple Ways to Eat Healthy
- How to Eat Whatever You Want Without Feeling Guilty
III. How to Stick to a Healthy Eating Habit
- Address the Root Problem of Unhealthy Eating
- How to Say No to Temptation
- This One Phrase Will Help You Eat Healthy Time After Time
- Where to Go From Here
The Science of Healthy Eating
Every nutritionist and diet guru talks about what to eat. Instead, I'd like to discuss why we eat the way we do and how we can change that. The purpose of this guide is to share the science and strategy you need to get the results you want.
Now, the benefits of good nutrition are fairly obvious to most of us. You have more energy, your health improves, and your productivity blossoms. Healthy eating also plays a huge role in maintaining a healthy weight, which means a decreased risk of type 2 diabetes, certain cancers, heart problems, high blood pressure, and a host of other health ailments. (Genetics also plays a significant role. I'm not some crazy person who thinks genes don't matter.)
But if there are so many good reasons for healthy eating, why is it so difficult to actually do? To answer that question, we should start by learning why we crave junk food.
Why We Crave Junk Food
Steven Witherly is a food scientist who has spent the last 20 years studying what makes certain foods more addictive than others. Much of the science that follows is from his excellent report, Why Humans Like Junk Food.
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. Food scientists will test for the perfect amount of fizzle in a soda. These elements 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.
How Food Scientists Create Cravings
There is 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 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.
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.”
“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, and 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.
These factors all combine to make processed food tasty and desirable to our human brains. When you combine the science behind these foods with the incredible prevalence of food (cheap fast food everywhere), eating healthy becomes very hard to do.
How to Make Healthy Eating Easier
Most people think that building better habits or changing your actions is all about willpower or motivation. But the more I learn, the more I believe that the number one driver of behavior change is your environment.
Your environment has an incredible ability to shape your behavior. Nowhere is this more true than with food. What we eat on a daily basis is often a result of what we are presented.
The Importance of Environment for Healthy Eating
Anne Thorndike is a primary care physician at Massachusetts General Hospital in Boston. Thorndike and her colleagues conducted a six-month study that was published in the American Journal of Public Health.
This study secretly took place in the hospital cafeteria and helped thousands of people develop healthy eating habits without changing their willpower or motivation in the slightest way. Thorndike and her team utilized a concept known as “choice architecture.” Choice architecture is just a fancy word for changing the way the food and drinks are displayed, but, as it turns out, it makes a big difference.
The researchers started by changing the choice architecture of the drinks in the cafeteria. Originally, there were three main refrigerators, all of which were filled with soda. The researchers made sure that water was added to each of those units and also placed baskets of bottled water throughout the room.
The image below depicts what the room looked like before the changes (Figure A) and after the changes (Figure B). The dark boxes indicate areas where bottled water is available.
What happened? Over the next 3 months, the number of soda sales dropped by 11.4 percent. Meanwhile, bottled water sales increased by 25.8 percent. Similar adjustments and results were made with food options. Nobody said a word to the visitors who ate at the cafeteria. The researchers simply changed the environment and people naturally followed suit.
Choice architecture is even more important when you're already stressed, tired, or distracted. If you're already worn-down, you’re probably not going to go through a lot of effort to cook a healthy dinner or fit in a workout. You’ll grab or do whatever is easiest.
That means that if you take just a little bit of time today to organize your room, your office, your kitchen, and other areas, then that adjustment in choice architecture can guide you toward better choices even when your willpower is fading. Design for laziness.
How to Eat Healthy Without Noticing
Brian Wansink is a professor at Cornell University, and he has completed a variety of studies on how your environment shapes your eating decisions. Many of the ideas below come from his popular book, Mindless Eating (audiobook). Here are some of his best practical strategies for using choice architecture to make healthy eating easier.
1. Use smaller plates. Bigger plates mean bigger portions. And that means you eat more. According to a study conducted by Wansink and his research team, if you made a simple change and served your dinner on 10-inch plates instead of a 12-inch plate, you would eat 22% less food over the course of the next year.
On a related note, if you’re thinking “I’ll just put less food on my plate” … it’s not that simple. The picture below explains why. When you eat a small portion off of a large plate, your mind feels unsatisfied. Meanwhile, the same portion will feel more filling when eaten off of a small plate. The circles in the image below are the same size, but your brain (and stomach) doesn’t view them that way.
2. Want to drink less alcohol or soda? Use tall, slender glasses instead of short, fat ones.
Take a look at the image below. Is the horizontal or vertical line longer?
As it turns out, both lines are the same length, but our brain has a tendency to overestimate vertical lines. In other words, taller drinks look bigger to our eyes than round, horizontal mugs do. And because height makes things look bigger than width, you’ll actually drink less from taller glasses. In fact, you will typically drink about 20% less from a tall, slender glass than you would from a short, fat glass. (Hat tip to Darya Pino for originally sharing this image and idea.)
3. Use plates that have a high contrast color with your food. As I mentioned in this article, when the color of your plate matches the color of your food, you naturally serve yourself more because your brain has trouble distinguishing the portion size from the plate. Because of this, dark green and dark blue make great plate colors because they contrast with light foods like pasta and potatoes (which means you’re likely to serve less of them), but don’t contrast very much with leafy greens and vegetables (which means you’re likely to put more of them on your plate).
4. Display healthy foods in a prominent place. For example, you could place a bowl of fruits or nuts near the front door or somewhere else that you pass by before you leave the house. When you’re hungry and in a rush, you are more likely to grab the first thing you see.
5. Wrap unhealthy foods in tin foil. Wrap healthy foods in plastic wrap. The old saying, “out of sight, out of mind” turns out to have some truth to it. Eating isn’t just a physical event, but also an emotional one. Your mind often determines what it wants to eat based on what your eyes see. Thus, if you hide unhealthy foods by wrapping them up or tucking them away in less prominent places, then you are less likely to eat them.
6. Keep healthy foods in larger packages and containers, and unhealthy foods in smaller ones. Big boxes and containers tend to catch your eye more, take up space in your kitchen and pantry, and otherwise get in your way. As a result, you’re more likely to notice them and eat them. Meanwhile, smaller items can hide in your kitchen for months. (Just take a look at what you have lying around right now. It’s probably small cans and containers.)
What Should I Eat?
As I mentioned at the outset, this is not a guide about what to eat. It's a guide about why we eat the way we do and how to do something about it. That said, I'll offer two suggestions regarding what to put on your plate.
1. Eat more greens. There isn't a consensus on the best diet, but pretty much everyone agrees on one thing: eat more veggies. You'll be hard-pressed to find a single diet that doesn't think eating more plants is a good idea.
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.
Healthy eating 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 fall in love with boredom.)
Two Simple Ways to Eat Healthy
The main idea of most good diets is the same: eat whole foods that are unprocessed and that grew or lived outdoors. Some of them have different variations — no animal products, no grains, etc. — but most of them fit the general “real food” framework.
The problem is that — if you’re anything like me — you will eat whatever is close to you, whether it came from Mother Nature or not. As a result, the best strategy is to surround yourself with healthy food.
1. Use the “Outer Ring” Strategy. When I go to the grocery store, I only walk around the “outer ring” of the store. I don’t walk down the aisles. The outer ring is where the healthy food usually lives: fruits, vegetables, lean meats, fish, eggs, and nuts. These are items that grew or lived outdoors. That’s what I eat.
The aisles are where all of the boxed and processed stuff is placed. Don’t go down those aisles and you won’t buy those foods. Don’t buy those foods and they won’t be around for you to eat. Try this the next time you go to the store and do your best to not to make exceptions.
Sure, there will be the occasional time that you’ll need to go down an aisle to pick up spices or grab a bottle of olive oil, but this is rare. The last three times I’ve been at the grocery store, I have easily stayed on the “outer ring” and I bet you can do the same.
How to Eat Whatever You Want Without Feeling Guilty
2. Never Miss Twice. I think life is meant to be lived joyfully. I have no desire to judge myself for eating pizza or to feel guilty for drinking a beer. But, I also know that I feel much better when I eat healthy.
In order to balance the two, I have a simple rule that I try to follow: whenever I eat an unhealthy meal, I follow it with a healthy one.
Missing once is fine, but I never want to miss a healthy meal twice. Top performers make mistakes like everyone else, but they get back on track faster than most people. That’s what I try to do with my diet. I don’t worry about having fun and I try to enjoy life, but I also use this simple rule to guide me back toward a healthy diet as quickly as possible.
Address the Root Problem of Unhealthy Eating
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 simple breathing techniques or a short guided meditation. Or something more physical like exercise or making art.
How to Say No to Temptation
Learning how to say no is one of the most useful skills you can develop, especially when it comes to living a healthy life. Research is starting to show that small changes can make it easier for you to say no, resist temptation and stick to healthy eating habits.
In a research study published in the Journal of Consumer Research, 120 students were split into two different groups.
The difference between these two groups was saying “I can’t” compared to “I don’t.”
One group was told that each time they were faced with a temptation, they would tell themselves “I can’t do X.” For example, when tempted with ice cream, they would say, “I can’t eat ice cream.”
When the second group was faced with a temptation, they were told to say “I don’t do X.” For example, when tempted with ice cream, they would say, “I don’t eat ice cream.”
After repeating these phrases, each student answered a set of questions unrelated to the study. Once they finished answering their questions, the students went to hand in their answer sheet, thinking that the study was over. In reality, it was just beginning.
As each student walked out of the room and handed in their answer sheet, they were offered a complimentary treat. The student could choose between a chocolate candy bar or a granola health bar. As the student walked away, the researcher would mark their snack choice on the answer sheet.
The students who told themselves “I can’t eat X” chose to eat the chocolate candy bar 61% of the time. Meanwhile, the students who told themselves “I don’t eat X” chose to eat the chocolate candy bars only 36% of the time. This simple change in terminology significantly improved the odds that each person would make a more healthy food choice.
The One Phrase That Will Help You Eat Healthy
Your words help to frame your sense of empowerment and control. Furthermore, the words that you use create a feedback loop in your brain that impacts your future behaviors.
For example, every time you tell yourself “I can’t”, you’re creating a feedback loop that is a reminder of your limitations. This terminology indicates that you’re forcing yourself to do something you don’t want to do.
In comparison, when you tell yourself “I don’t”, you’re creating a feedback loop that reminds you of your control and power over the situation. It’s a phrase that can propel you toward breaking your bad habits and following your good ones.
Heidi Grant Halvorson is the director of the Motivation Science Center at Columbia University. Here’s how she explains the difference between saying “I don’t” compared to “I can’t”…
“I don’t” is experienced as a choice, so it feels empowering. It’s an affirmation of your determination and willpower. “I can’t” isn’t a choice. It’s a restriction, it’s being imposed upon you. So thinking “I can’t” undermines your sense of power and personal agency.
“I don’t” is experienced as a choice, so it feels empowering. “I can’t” isn’t a choice. It’s a restriction, it’s being imposed upon you.
In other words, the phrase “I don’t” is a psychologically empowering way to say no, while the phrase “I can’t” is a psychologically draining way to say no.
Perhaps most importantly, a change in language leads to a change in mindset. You can now utilize your new, empowered mindset in all future situations, which is why a subtle shift can lead to very different outcomes over the long-run.
Where to Go From Here
I hope you found this short guide on healthy eating useful. If you're looking for more ideas on how to eat healthy, then check out my full list of healthy eating articles below.
All Healthy Habits Articles
This is a complete list of articles I have written on building healthy habits. Enjoy!
- 10 Simple Ways to Eat Healthy Without Thinking, Backed by Science
- What Happens to Your Brain When You Eat Junk Food
- 10 Common Mistakes That Prevent You From Being Happy and Healthy Today, Backed by Science
- What I've Learned from 2 Years of Intermittent Fasting
- Effortless Ways to Lose Weight and Eat Healthy
- Learning From Superhumans: The Incredible Fitness and Success of Jack LaLanne
- Answers to the Most Common Intermittent Fasting Questions
- How to Start Eating Healthy (And Actually Stick to It)
- 12 Lessons Learned from 1 Year of Intermittent Fasting
- The Beginner's Guide to Intermittent Fasting