I get asked about calories all the time. Do we need to count them? Do calories really matter? And is one calorie exactly the same as another calorie? The answer is both yes and no.
Scientifically, a calorie is simply a unit of energy. So in that sense, 100 calories is 100 calories, whether those calories come from chocolate, avocado, chicken, olive oil or broccoli. And calories do matter when it comes to body weight. Over time, if we consistently consume more energy than our body uses, the excess can contribute to weight gain; if we consistently consume less energy than we use, weight loss can occur.
But this is where it gets much more interesting, because 100 calories of one food can have a very different effect on us from 100 calories of another. Imagine 100 calories of chocolate and 100 calories of avocado. They contain the same amount of energy, but they’re nutritionally very different. Avocado provides fibre, unsaturated fats, vitamins and minerals and may contribute differently to fullness. Chocolate — depending on the type — may contain considerably more added sugar and less fibre and can be very easy to eat beyond 100 calories. The calories are equivalent as units of energy; the foods aren’t equivalent as nutrition.
The same applies if we compare 200 calories of sweets with 200 calories of eggs, yoghurt, lentils or vegetables. Protein has a particularly interesting effect because our bodies use more energy digesting and processing protein than they do fat, and protein can help us feel full while supporting muscle. Fibre can also influence fullness, digestion and gut health. The physical structure of food matters too. In other words, our bodies aren’t simply calculators receiving anonymous little units called calories.
So does calorie counting work? It certainly can. For some people, it’s incredibly useful because it teaches portion awareness. You may discover that the handful of nuts you’ve been casually eating is actually three handfuls, that the olive oil being poured freely into the pan contains considerably more energy than you realised, or that drinks and snacks are contributing a substantial amount to your daily intake. Tracking for a short period can be a really useful educational exercise.
But I don’t think everybody needs to count calories, and I certainly don’t think everybody needs to count them forever. Food labels aren’t perfectly precise, our energy expenditure isn’t perfectly precise, fitness watches can only estimate calories burned, and our own bodies aren’t identical machines. More importantly, calorie counting can make some people overly focused on numbers and less interested in the quality of what they’re eating.
You could theoretically create a calorie-controlled diet containing lots of highly processed food and very few vegetables, or eat the same number of calories from a varied diet containing protein, vegetables, fruit, beans, whole grains, nuts, seeds and healthy fats. The numbers might look similar on an app, but those two diets aren’t providing the same nutrition.
This is why I use calories as information rather than a judgement. If somebody wants to lose weight and genuinely has no idea how much they’re eating, looking at calories for a while can be enlightening. But then I want to move beyond the numbers and teach them to look at the actual food.
Where’s your protein? Where’s your fibre? Where are your plants? Are you getting healthy fats? Is this meal going to satisfy you? Are you actually hungry? How large is the portion? How does this way of eating make you feel?
Calories matter, but calories aren’t the whole story.
So yes, 100 calories of chocolate contains the same amount of energy as 100 calories of avocado. But your body doesn’t just need energy.
It needs nutrition.
And that’s why I would never choose my food simply by looking for the lowest number on the packet.
Selena
Personal Trainer, Yoga Teacher & Wellbeing Coach
In Flow Wellbeing Studio, Cheltenham
