Maintenance calories: your body already ran the experiment

Every calorie calculator on the internet is guessing about you. It takes your age, your height, your weight, and drops them into a formula built from a pile of other people. Then it guesses how much you move. That’s two guesses stacked on top of each other. Your body isn’t guessing. It already ran the experiment, and it wrote the answer down in your weight.

What maintenance actually is

Maintenance is one number. It’s the calories where your weight holds flat. Eat that, and the trend goes sideways for weeks. Eat under it, you drop. Over it, you climb. Every formula on every website is just trying to predict that one number. You don’t have to predict it. You can measure it.

The four-week experiment

Log everything you eat for four weeks. All of it. The olive oil in the pan, the two bites off your kid’s plate, the Tuesday beer. Weigh in every morning and watch the trend, not the daily bounce. At the end, do some easy arithmetic.

Take your average daily calories across those weeks. Then look at what the trend weight did. If it held flat, that average is your maintenance. Done. That’s the number. If you lost about a pound a week, you were running roughly 500 calories a day under maintenance (3,500 calories to a pound, split across seven days), so add those 500 back. Lost half a pound a week? Add 250. The scale did the measuring. You just read it.

The one way this breaks is a soft log. A “close enough” log hands you a close-enough number, which is a wrong number wearing a nice shirt. So weigh the food for these four weeks. Just four. You are not doing this forever. You’re calibrating an instrument once.

Why your number beats the calculator’s

Two people at the same height and weight can have maintenance numbers 500 calories apart. Different jobs, different fidgeting, different amounts of muscle, different guts. A formula can’t see any of that. Your logbook sees all of it, because it’s watching the one body that actually matters here.

Four weeks of honest logging buys you a number you can trust for the next year. That’s a great trade. Go run the experiment. You did the hard part the moment you decided to log it straight, champ.