Eat more to lose weight? The paradox of 'high energy flux'

We reduce portions, skip meals, eliminate entire food categories, and try to get by on as few calories as possible.

At first, the scale goes down. Then fatigue sets in. We move less. We feel cold. We think about food more. Training becomes difficult. Hunger increases. And, a few months later, many people end up regaining the weight they lost.

The idea behind high energy flux is simple: rather than trying to run your body on less and less energy, build a body that uses more energy. And this completely changes the way we think about weight loss.

First, something fundamental: an energy deficit remains necessary

I want to be very clear on this point. The laws of physiology do not disappear. To lose body fat, the body must, over a sufficiently long period, use more energy than it stores.

So no: eating more calories than you expend will not magically make you lose fat. When I talk about 'eating more,' I am talking about a much smarter strategy.

Eating more satiating, nutrient-rich foods. Sometimes more in volume. Enough protein. Minimally processed foods. Vegetables and fiber. Quality fat sources. And enough energy to be able to move, train, recover, and preserve muscle mass.

The result can be surprising: you sometimes feel as though you are eating much more than before, while your diet is actually better controlled in terms of energy.

The problem with 'always less'

Imagine someone who expends a great deal of energy every day. They walk. They work. They exercise. They have a decent amount of muscle mass. Then they decide to lose weight by drastically cutting back on what they eat.

At first, they lose weight. But our body is not a passive calculator. When a significant energy restriction is prolonged, it adapts. This is what we refer to notably as metabolic adaptation or adaptive thermogenesis: energy expenditure can decrease beyond what one would simply expect from weight loss.

But something much simpler also happens: you start moving less.

Your body economizes without you realizing it

When you are short on energy, you do not necessarily spend the whole day lying down. The changes are often far more subtle. You walk a little less. You sit more. You are more inclined to take the elevator. You move less when you talk. You get up less often. You put off your workout. Your training becomes less intense.

All of these small energy expenditures make up what we call NEAT — Non-Exercise Activity Thermogenesis: the energy expended in all movements that correspond neither to resting metabolism, nor to digestion, nor to an actual exercise session. And this NEAT can represent a considerable difference between two people.

You thought you were simply eating less. But gradually, your body also spends less. This is what I call, to put it simply, a low energy flux state: little energy comes in, little energy goes out, and the body becomes more and more frugal.

High energy flux: another way of thinking

Now, let's imagine a different strategy. Rather than looking for the minimum amount of food you can manage to sustain, we aim to build an active body.

You eat enough to train properly. You increase your daily activity. You walk more. You do strength training. You maintain or build your muscle mass. You recover properly. And your diet remains satisfying enough for you to maintain this strategy for months rather than a few weeks.

The energy coming in is greater than in an extremely restrictive diet. But so is the energy going out. That is high energy flux. And as long as a reasonable energy deficit persists, you can continue to improve your body composition.

"Eating more" means above all eating differently

This is probably the most important nuance. Take 500 kilocalories from highly palatable ultra-processed foods: the volume can be relatively small, they can be consumed very quickly, satiety can be limited, and a few hours later you may be hungry again.

Now compare that with a diet made up of proteins, vegetables, whole fruits, legumes according to tolerance, minimally processed carbohydrate sources and quality fats. For a comparable energy intake — sometimes even a lower one — the food volume can become much greater.

You therefore have the impression of eating more. But your nutritional density increases and the overall energy density of your diet can decrease. That is exactly what we are looking for.

Proteins become particularly important

When a person wants to improve their body composition, proteins occupy a central place. Why?

First, they contribute to the maintenance and building of muscle mass. Second, they generally have a strong satiating effect. Third, their thermic effect is greater than that of carbohydrates and especially fats: the body expends more energy to digest, absorb and metabolise them.

This obviously does not mean that one should eat exclusively proteins. It means that, in many poorly constructed weight-loss diets, protein intake is one of the things we need to monitor particularly closely. Because losing weight while losing a great deal of muscle is not the goal.

I don't just want you to lose weight

Imagine two people who each lose ten kilograms. The first loses mainly fat while preserving their muscle mass. The second loses fat, but also a significant amount of muscle. On the scale: –10 kg for both. Physiologically, however, the results are very different.

My goal is therefore not simply to lose weight. My goal is to improve body composition: reduce excessive fat mass, particularly visceral fat when it is present; preserve — and when possible develop — muscle mass; maintain physical performance; improve metabolic health; and build a body capable of sustaining these results over the long term.

To lose fat, you sometimes have to start by building muscle

Muscle is far more than an aesthetic element. It is a tissue that is essential to our metabolic health. It represents a major site of glucose utilisation and plays an important role in insulin sensitivity and functional health.

And above all, when you have enough energy to train properly, you can create a quality muscular stimulus. This is where nutrition and exercise become inseparable: you need to fuel training so that training can transform the body. Starving yourself while asking your body to build — or even simply to preserve — muscle is rarely the smartest strategy.

And what about sleep in all of this?

It is fundamental. Very restrictive diets can increase hunger, food-related preoccupations and, in some people, make sleep more difficult. Yet poor sleep considerably complicates weight management: it alters appetite regulation, it can impair insulin sensitivity, and it frequently increases cravings for highly energy-dense foods. And above all: when you are exhausted, you move less.

Once again, everything is connected. Nutrition, physical activity, muscle, sleep, stress, metabolism: these are not six independent problems. It is a system.

Another common misconception: carbohydrates are not the enemy

The problem is not eating carbohydrates. Fruit contains them. Legumes contain them. Potatoes contain them. Whole grains contain them. And depending on a person's physical activity level and metabolic situation, carbohydrates can perfectly well be part of a healthy diet.

What we are primarily looking to limit are ultra-processed foods that are highly energy-dense and poorly satiating, particularly when they combine refined sugars, refined starches, fats and high palatability. The problem is therefore far more complex than 'carbohydrates = bad'.

Your body needs energy to function

This is something we sometimes forget in diet culture. Your body doesn't only use energy for walking. It uses energy to maintain your temperature, to fuel your brain, your immune system, to renew your tissues, to synthesise proteins, to support liver function, to digest, to repair muscles after exercise, and to produce and regulate the many molecules that are essential to your physiology.

Food is not the enemy of your metabolism. It is its fuel and part of its building materials. The problem lies in supplying the wrong fuel, in the wrong quantities, with too little movement.

The best diet is not the one that teaches you to survive on as little as possible

It is the one that allows you to build a lifestyle your body can sustain. You need to be able to eat properly, have enough energy, train, walk, work, sleep, preserve your muscle mass, control your hunger, and continue living normally.

If your nutritional strategy leaves you exhausted, obsessed with food, constantly hungry, and unable to train, ask yourself one question: is this truly a strategy I will be able to maintain?

So, can you really eat more and lose fat?

Yes — but understand clearly what that means. It doesn't mean arbitrarily increasing calories. It sometimes means eating more food by volume and more nutrients, while choosing foods that are less energy-dense and more satiating.

It means providing enough protein. It means fuelling your body sufficiently to preserve muscle mass and support training. And above all, it means: increasing the energy your body is capable of using, rather than continually seeking to reduce the energy you give it. That is what I call high energy flux.

And if you were to take away just one sentence today: don't aim to feed your body just enough to survive; feed it intelligently so that it can move, build muscle, function, and age in better health. To lose fat sustainably, the answer is sometimes not to eat less and less, but to eat better in order to be able to expend more.