If you think that your slow metabolism is plotting against your skinny jeans, you’re not alone. But the reality is, metabolism isn’t just a secret code for weight loss—it’s the body’s way of operating, full stop. Intrigued? You should be. Because when it comes to sabotaging your weight loss, some daily habits (and not-so-daily surprises) can sneakily stall your progress without you even realizing it.
Understanding Metabolism: More Than Just a Weight-Loss Buzzword
Let’s set the record straight: metabolism isn’t only about slimming down. As dietitian-nutritionist Nathalie Négro explains, metabolism is really the term for how the human body works. Think of it as the engine under the hood—managing everything from how you use carbs for fuel (glucidic metabolism) to how energy is used and produced (energetic metabolism). So, it’s way more complex than just a number on a scale.
The star of this show is the basal metabolic rate (BMR), which represents a whopping 60% to 70% of your daily energy use. To break it down, your BMR is the number of calories your body burns just to keep you alive while you’re lounging, Netflixing, or even sleeping—simply to keep your vital organs humming, your muscles slightly engaged, and your body temperature steady at around 37.5°C. And if you’re a kid or teenager, BMR is also fueling your growth!
Basal Metabolic Rate: What Determines It?
Wondering how to figure out your own BMR? It’s expressed in calories (Kcal). Here’s a quick cheat sheet:
- For women: Multiply your weight (in kilos) by 20
- For men: Multiply your weight (in kilos) by 25
This gives you the bare minimum you need just to function—what Négro calls your « vital minimum. » For example, a woman weighing 55 kg requires at least 1100 Kcal a day for her body to function correctly. If you want to get fancier, medical professionals turn to impédancemetry (no, not a Harry Potter spell) to determine your muscle mass, since BMR mostly supports your muscles and their tone—even while you sleep.
But not everyone burns calories at the same speed, and that’s where things get interesting (or, if you’re trying to lose weight, a tad infuriating). BMR depends on a few basic things, like:
- Sex
- Age
- Height
- Weight
- Muscle mass
In short, those with more muscle mass generally have a higher BMR. Yes, your gym-obsessed friend does have a metabolic edge.
What Secretly Slows Down Your Metabolism?
Here’s where the plot thickens. Sometimes, people consume a suspiciously low number of calories at rest. But why does this metabolic snail race happen?
- Certain illnesses: Conditions like hypothyroidism (which affects 1% to 2% of the French population, mostly women over 40) can put the brakes on your BMR.
- Medications: Some drugs, like mood stabilizers used for bipolar disorder, can lead to a less efficient metabolism.
- Endocrine disruptors: Sneaky chemicals in the environment (perturbateurs endocriniens) can slow down overall energy metabolism.
Feeling like your metabolism is on a coffee break? These factors may be the reason.
Boosting Your Metabolism—And Your Weight-Loss Results
Luckily, you’re not powerless against a slow BMR. If you want your metabolism to burn more calories at rest (and who doesn’t?), physical activity is your golden ticket. According to Nathalie Négro, the BMR’s main purpose is to maintain muscle mass and muscle tone throughout the body. So the more muscle you have, the higher your BMR—mathematically speaking!
Pick your favorite activity: cycling, fitness training, Nordic walking, hiking, swimming, Pilates, yoga, dancing, zumba, climbing… Take your pick and get moving! The key is to find a sport or activity you enjoy and can stick with, helping you lose weight more quickly without resorting to extreme diets.
Of course, no weight loss plan is complete without balanced eating, especially in tandem with your physical exploits. That means less sugar, less salt, fewer saturated fats and ultra-processed foods, and more of the good stuff:
- Fruits and vegetables
- Animal and vegetable proteins
- « Good » fats
Don’t hesitate to seek advice from your GP or a dietitian-nutritionist—there’s no shame in getting a little expert help to steer your metabolic ship in the right direction.
So, the next time you’re tempted to curse your metabolism, remember: it’s not just about burning fat. By moving more, eating smarter, and being aware of the sneaky things that can sabotage your efforts, you can give your body’s engine the tune-up it deserves—and put yourself back in the weight-loss driver’s seat.
John is a curious mind who loves to write about diverse topics. Passionate about sharing his thoughts and perspectives, he enjoys sparking conversations and encouraging discovery. For him, every subject is an invitation to discuss and learn.
