A new weight loss study was released this week, reported by various news outlets with the following headline:
Counting calories not key to weight loss, study finds.
The description went on to explain:
People in the study who cut back on added sugar, refined grains and highly processed foods while eating plenty of vegetables and whole foods — without worrying about cutting calories or portion sizes — lost significant amounts of weight over the course of a year.
The headline might be misleading because despite not having to restrict portions, the subjects still ended up consuming fewer calories.
This touches on some important issues when it comes to calorie counting and weight loss.
Calories do count. As far as we know, there is nothing we can do to change the reality of energy balance in the body. Expend more calories than you consume, and you lose weight. Consume more calories than you expend, and you gain weight. This is the law of energy balance.
However, as this study shows, there are factors that you can influence upstream of the energy balance equation.
If your diet consists of more satiating foods, then you may eat fewer calories without trying to. You are intervening at the level above calories in/out, without challenging the idea of energy balance itself.
The formula still holds true; you’re just pouring less into one side of it in the first place.
As this study points out, it just so happens that many whole foods are also quite satiating, which lends further weight to the axiom of basing your diet around whole, unprocessed foods.
It is also the case that highly processed foods are often calorie-dense and highly palatable. This is a potent combination that means a lot more food is inside you before your brain or belly know what’s going on. In short, these processed foods are often very easy to overeat.
If a person can include more whole foods in their diet, then they may unconsciously reducing their caloric intake through the magic of eating food that makes you feel fuller for longer.
As one of the authors commented:
…it is not that calories do not matter. After all, both groups ultimately ended up consuming fewer calories on average by the end of the study, even though they were not conscious of it. The point is that they did this by focusing on nutritious whole foods that satisfied their hunger.
For example, 500 calories of jelly babies is (for most people) not going to keep them full as long as 500 calories of porridge: the simple sugars are quickly broken down, leading to volatile blood sugar levels (unless you’re mid-marathon) and the resulting slump and hunger mean you’ll be craving food sooner.
We generally want to eat foods that burn like a well-built fire, rather than a grenade in a furnace.
Satiation does vary individually, but high protein, high fibre and carbohydrate-rich foods generally score highest when it comes to keeping people full.
On the topic of macronutrients, this study also noted that its results were independent of whether the participants ate a low-fat or low-carb diet.
The same effect would likely be seen in any diet where someone increases their protein intake. Protein is highly satiating, and furthermore the body requires extra energy to digest and store it.
Low carb diets can create the deficits required for weight loss. But the secret ingredient is likely the increased protein and higher consumption of more satiating whole foods, rather than any magic in carbohydrate restriction itself. We don’t need to hate on the carbs.
So should we still be telling people to count calories?
The linked news article notes the advice from The Center for Disease Control and Prevention, which tells people to:
Write down the foods you eat and the beverages you drink, plus the calories they have, each day.
This is setting people up for failure. Even someone with a deep interest in nutrition is going to struggle with the above. It is extraordinarily time-consuming, easy to miscalculate, psychologically draining, and does nothing to address food quality.
The hidden cost of this kind of advice is that most people won’t even bother, understanding what a faff it is track calories every day. This is not the message to send to people interested in weight loss.
None of this is to say calorie counting doesn’t work at all. It may be suitable for someone with specific body composition goals. But even then, calories on labels are not always accurate, and then you have to calculate your energy expenditure each day, which is a whole other guessing game.
It’s also not to deny the value of having some idea of caloric density. Some foods are incredibly delicious and dense—I’m looking at you peanut butter—and having a sense that you can consume several hundred calories in a few tablespoons is good to know.
But counting each calorie is tough, and should be a secondary strategy for people who really know what they’re doing. For most people, it’s simply not feasible. It makes the happiest human a miserable slave to numbers when they could likely achieve the results they’re looking for through simpler means.
Counting calories is not the same thing as the reality of energy balance (calories in/out), and that’s important because if we conflate the two, then we’re essentially telling everyone that they need to count calories to lose weight, which is a terrible idea.
So what should you do instead?
- Focus on eating whole, unprocessed foods. Build your meals around vegetables, legumes, nuts, meats, dairy, whole grains, fruit etc.
- Learn how to eyeball portion sizes. This is easy to learn and will get you most of the way there in terms of preventing overeating.
- If you’re not already active, look at introducing more movement into your life, specifically movement that brings you joy.
Calories count, but you probably don’t need to count them.