Body · Nutrition basics
What is a calorie deficit?
The short version
A calorie deficit means eating less energy than your body uses over time.
It's the underlying requirement for losing body fat. It doesn't need to be extreme.
The full version
What it is
When you consistently take in less energy than you use, your body makes up the difference from stored energy — including body fat. Over weeks and months, that's what drives fat loss.
Bigger isn't better
A bigger deficit can make the scale move faster at first, but excessive restriction tends to make training, hunger, recovery, energy and sticking with it all harder. You're also more likely to lose muscle along the way.
Make it sustainable
The question should be "what can I keep doing?", not "how little food can I survive on?". A moderate deficit, higher protein, regular training and plenty of filling foods usually works better over months. That's the idea behind the founder story, too.
What actually matters
Aim for a moderate deficit you can live with, keep protein up, keep training, and judge progress over weeks — not single weigh-ins. Under 18? The calculator won't set a deficit target.
Key takeaways
- 01Fat loss needs a deficit over time
- 02Moderate beats extreme
- 03Keep protein and training up
- 04Sustainable wins
Related
RELATEDView sources
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