Why Food Quality Is More Important Than Cutting Calories: The Energy Balance Equation
It’s all about calories. That’s been the standard weight loss advice for decades, starting with the first best-selling weight loss book, called “Diet and Health: With Key to the Calories” by Lulu Hunt Peters. It was published in 1918.
Focusing on calories for weight loss is still popular today, especially the “fact” that you have to reduce calories if you want to lose weight. Here is how this often plays out:
You start counting calories and realize that you’re eating more of them than you thought. “Oh no, I have to cut calories!”
You start buying low calorie foods at the supermarket, like low-fat ice cream and 100 calorie snack packs, you vow to give up your favorite foods like burgers and creamy pasta, and you try to stop eating for the day when you hit your calorie “budget”, even if it’s only lunchtime.
How do you think this will work out for you? Do you think you’ll feel satisfied and energetic, or hungry and lethargic? Do you think you’ll maintain a lifestyle like this? Most people don’t.
In fact, the vast majority of people who go on a diet, especially one that promotes lowering calorie intake, will give up within a few months and regain any weight they lost.
Calorie restriction is not the answer. Yes, calories are important, and if you want to lose weight you need to take in fewer calories than you use, but focusing on cutting calories is not the way to get there.
I know that’s confusing – How do you reduce calories if you don’t focus on them?
The Science of Calories and Energy Balance
Calories are a measure of energy. You take in energy from the food you eat and use that energy to keep your body systems working and to do physical activities.
If you take in more energy than you use, you are in a "calorie surplus" and the extra energy will be stored away. In other words, you gain weight.
If you use more energy than you take in, you are in a "calorie deficit" and you lose weight.
This is often illustrated by the “energy balance equation”. This equation states that body weight is equal to the balance between energy (calories) in and energy out:
If you decrease ENERGY IN by eating fewer calories and/or increase ENERGY OUT by exercising more, you lose weight:
Or, if you do the reverse, you gain weight:
Since this equation is always true (it’s based on the laws of thermodynamics), some people will argue that calories are all that matter. All you have to do is some simple math to figure out the numbers and then adjust the number of calories you take in and the number of calories you burn, and you can control your weight.
These people say that it doesn’t matter where those calories come from or what your food is made of, if you eat too many calories you will gain weight, and if you eat fewer calories you will lose weight.
This is the conventional “eat less, move more” advice that we’ve heard over and over for decades.
You can probably guess by now that I completely disagree with this advice. The clearest indication, in my opinion, that this is the wrong way to go about weight loss is simply that it hasn’t worked.
Many, many people have tried to lose weight by cutting calories and exercising more since this advice became popular, and guess what has happened? People are still gaining weight.
There has been an explosion in the prevalence of weight gain and obesity, along with chronic diseases. If it’s all about calories, why doesn’t cutting calories work?
Let’s put aside the fact that you have no idea how many calories you are taking in and how many you are burning, and nothing (not the nutrition facts label, not an online calorie calculator, not the display on the treadmill) can give you anything more than a very rough estimate.
The more important issue here is that this advice is unbelievably oversimplified. It assumes that ENERGY IN and ENERGY OUT in the energy balance equation are independent variables that you can simply manipulate however you want. That’s just plain wrong.
How Your Body Regulates Your Weight
Your body has an amazingly complex and intricate system for managing your weight. There are hundreds of factors, both physiological and psychological, that affect how your body digests and processes foods, what happens to those foods once they are digested, and how you feel and behave.
All of those factors are closely interrelated, you can’t change one thing without affecting another.
Your body wants to be in a state of balance at all times, and it will fight to hold onto body weight when you start changing your energy balance.
When you reduce the number of calories you eat, your body will respond by adjusting your hunger levels to encourage you to bring your calorie intake back to normal.
Think about what happens if you simply start eating less – you feel hungry (and maybe grumpy too). You can try to ignore those feelings of hunger, but sooner or later it will become overwhelming and you will need to eat.
Those hunger signals are your body’s way of surviving by making sure you have enough fuel and other substances coming in to keep you alive. You can’t fight your own body’s survival mechanisms, no matter how much willpower you have, at least not for long.
Your body will also adjust your energy levels to discourage you from moving so it can conserve calories. Again, how do you feel when you eat less? Full of energy and ready to tackle your workout? I doubt it.
Your body prompts you to eat more and move less by releasing hormones and other substances that make you feel hungry or tired, which guides your behavior.
It does all of this to conserve your body weight, to keep it stable. Sometimes the changes are so subtle that you don't realize they are happening.
It’s Just Not As Simple As Cutting Calories (Eating Less) Or Moving More
To be clear, I am not arguing that the energy balance equation is wrong. Your body weight is related to the amount of energy you take in and the amount of energy you expend. It’s just the weight loss advice based on this equation that's wrong.
What if we start trying another way? What happens if we stop thinking about our food in terms of how many calories are in it, and start thinking about it in terms of quality?
The Usual Weight Loss Advice, Based On The Energy Balance Equation
Remember again that the energy balance equation looks like this.
Let’s say I want to lose weight, so I go to a trainer or a dietitian, or the internet, and I am told: if you decrease your calorie intake then you will lose weight. I’m going to leave physical activity out of it just to simplify things here. So if we plug that in to the energy balance equation again, we get this:
Step 1 would be to cut calories, and then (step 2) body weight will decrease. We are coming at this equation from the left side and moving to the right.
This method focuses on quantity, how many calories you take in, but as we know that’s not an effective and sustainable method for long-term weight loss.
What Happens If We Focus On Quality Instead?
Food contains energy, but it also contains nutrients. Protein, fat, and carbohydrates are macronutrients, which serve important purposes in our bodies. There are also micronutrients: vitamins, minerals, phytochemicals and zoochemicals, as well as fiber and other compounds in foods.
All of these nutrients are essential for your body to function properly, and many of them have a direct effect on your weight control system, contributing to the complex signaling processes that regulate your energy balance.
Some foods are nutrient-dense. They contain a lot of nutrients relative to their calorie content. Whole, minimally processed foods are the best example of this. Vegetables, fruits, whole grains, legumes, lean proteins, and healthy fats like unrefined oils, nuts, seeds, etc. are full of nutrients. These are high quality foods.
Minimally processed basically means foods that are as close to their natural state as possible. They are sometimes processed a little, like when beans are dried and bagged, but they are not subjected to intense processing and they aren't full of additives and preservatives.Heavy processing, on the other hand, adds sugars, unhealthy fats, preservatives, additives, and other substances to foods, and usually strips them of their nutrients in the process.
White rice, for example, is the same as brown rice except it has had two layers removed, and those layers are the ones that contain most of the fiber, vitamins, and minerals. White rice is heavily processed, while brown rice is minimally processed and nutrient-dense.
When you eat a nutrient dense, high quality food, the nutrients send signals to your body which tell it what to do with that food. Each nutrient sets off a chain reaction.
Enzymes are activated or deactivated. Hormones are regulated. Neurotransmitters are released. Organs start doing their jobs. All of the nutrients in a particular food work together to give your body directions and help it work properly.
We evolved alongside the plants and animals in our food system, and our bodies know how to handle the nutrients in whole foods. When we eat these foods, our bodies function well, and they don’t need to fight back by trying to conserve energy.
In fact, our weight regulation system can let go of stored energy (in the form of body fat) when we are getting plenty of nutrients, and can make adjustments to bring us back into balance, this time at a lower body weight.
This happens without trying to cut calories, and without violating the energy balance equation. Let’s see how. Let’s say you are having a hard time losing weight, in fact you’re gaining weight.
Remember that conventional wisdom says that this is what must be happening, because of the energy balance equation:
Again, we are moving from left to right in this equation. You must be eating too many calories which is causing your body weight to increase. But why do we need to read the equation in that direction?
Where in the original equation is there an arrow pointing in a certain direction? I don’t see one, do you?
Let’s think about this in a different way.
Think about a teenage boy. At a certain age, he goes through a growth spurt. He shoots up 3 inches in a matter of a few months. His bones are getting longer and bigger, and his muscles, organs, brain, and everything else in his body are also growing. He is putting on body weight.
According to the energy balance equation, if he is putting on weight then his energy intake must also be going up, because it takes energy to grow.
Does he wake up one morning and think – “It’s time for a growth spurt, I better start eating more so that my bones will get bigger…”. Of course not.
He just feels hungry, so he eats more. His genes are sending signals to his body that it’s time to grow, his body starts to get bigger, and to support that growth his hunger levels go up, which prompts him to eat more.
In this case, we are starting from the right side of the equation and moving left. In step 1, the body is getting signals to grow, which then causes energy intake to go up (step 2). The energy balance equation is still true here, only the order of events has changed.
Pregnancy is another good example of this phenomenon in action. A pregnant woman’s body receives signals from within her cells that she needs to increase her weight to support a growing fetus, and her body responds by increasing hunger levels to bring her energy intake up.
A Better Way To Approach Weight Loss
Instead of trying to manipulate the number of calories we eat and hoping that our body responds by lowering our body weight (which it might not do, instead it might just adjust hunger levels or energy expenditure to bring us back into balance), we should focus on providing our body what it needs to regulate our weight better.
When we take this approach, we work with our body instead of against it. We allow our body to let go of unneeded energy stores by giving it the signals and the raw materials it needs to do so.
If we look at our energy balance equation one more time, here is what is happening when we focus on eating more whole, minimally processed foods.
First (step 1) the fiber and other nutrients in the food cause it to be absorbed and digested slowly, avoiding spikes in insulin and other hormones that would cause your body to compensate.
The nutrients signal your body systems to work properly, and they give your muscles, brain, and other organs what they need to function well.
Among those organs are your fat cells, which get the signal to release some of their stored fat so it can be used.
Your body and brain senses that you have the energy and nutrients you need, so it sends signals of satisfaction, making you feel full, and you eat less. You feel energized.
Those feelings of satisfaction and decreased hunger cause you to take in less energy, and since you feel more energetic, you move more.
Step 2: Your ENERGY IN goes down, and your ENERGY OUT goes up.
Again, the energy balance equation is still true here. We haven't violated the laws of thermodynamics.
This is the difference between focusing on eating more quality food and focusing on eating less calories. The end result is the same - your energy intake goes down and you lose weight - but it happens in very different ways.
One way makes you feel satisfied and energetic (and improves your health), and the other makes you feel hungry and tired. Which method do you think you could maintain indefinitely?
You don’t even need to eat only quality foods, just more of them. You can still enjoy highly processed foods sometimes, just have them in small amounts and make sure most of your food is minimally processed.
I know it’s hard to let go of the idea that weight is all about calories. That way of thinking is everywhere and it’s been drilled into our brains for years. It took me a long time to figure it out, and this is what I do for a living!
If you want to lose weight and keep it off in a healthy and sustainable way, it’s time to acknowledge that focusing on calories is not the answer. Instead, start focusing on eating more high quality food to signal your body to control its weight more effectively and give it the nutrients it needs to do that. The rest will take care of itself.
If You Need Help
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