Eating 1,000 Calories Per Day Without Losing Weight?

“I’m eating 1,000 calories per day and not losing weight,” said the person not eating 1,000 calories per day.

They might think they’re only eating that much, but consider the following resting metabolic rates (the amount of calories burned at rest):

• 200-pound man: ~1,900 calories per day
• 150-pound man: ~1,700 calories per day
• 150-pound woman: ~1,500 calories per day
• 100-pound woman: ~1,100 calories per day

Thus, it requires about 1,100 calories of energy just to keep a 100-pound woman alive, and if she were bedridden, she’d still lose weight (albeit slowly) eating just 1,000 calories per day.

Now consider how total daily energy expenditure changes with just 1-to-3 hours of exercise per week:

• 200-pound man: ~,2400 calories per day
• 150-pound man: ~2,100 calories per day
• 150-pound woman: ~1,900 calories per day
• 100-pound woman: ~1,600 calories per day

Thus, while it’s essentially impossible to eat less than, say, 1,200 calories per day without losing weight, it’s remarkably easy to think you’re eating less than 1,200 calories per day without losing weight, when in fact, you’re eating a lot more than that.

In most cases, this occurs through a consistent combination of oversized portions and habitual snacking, but sometimes it’s more insidious.

Sometimes, it looks something like this:

• Monday: 🥚🧀🍏🥗🍗🥑🥩🥦🌊 (~1,800 calories per day)
• Tuesday: 🥚🧀🍏🥗🍗🥑🥩🥦🌊 (~1,800 calories per day)
• Wednesday: 🥚🧀🍏🥗🍗🥑🥩🥦🌊 (~1,800 calories per day)
• Thursday: 🥚🧀🍏🥗🍗🥑🥩🥦🌊 (~1,800 calories per day)
• Friday: 🥚🧀🍏🥗🍗🥑🥩🥦🌊 (~1,800 calories per day)
• Saturday: 🥞🥓🍔🍟🥤🍩🍕🍺🍦 (~4,000 calories per day)
• Sunday: 🥞🥓🍔🍟🥤🍩🍕🍺🍦 (~4,000 calories per day)

Average daily calorie intake Monday through Friday? 1,800. Average daily calorie intake Monday through Sunday? 2,400.

And so, if this person were burning ~2,300 calories per day throughout the week, they’ll lose nearly a pound of fat by the weekend, but then, if they were burning just ~2,000 calories per day on Saturday and Sunday, they’ll gain it all back by the time they return to “clean eating.”

So, here’s the takeaway:

Energy balance is simple, but it isn’t forgiving, and losing weight is straightforward, but it isn’t easy.