[dbrunsek]

"I've lost 30lb in four months without eating less or moving more."

- That's not impossible. However you've probably used drugs affecting your metabolism to increase your expenditure.

"How accurately are you really measuring your calories out, and how your diet and exercise impacts that?"

- Why would measuring anything affect how physiology and physics work? (And yes, energy expenditure and consumption can be measured extremely precisely in labs.)

"Or how the composition and combination and timing of the foods you eat impacts your digestion (calories in)?"

- In healthy people it doesn't.

I'm sorry to tell you but you were eating less than you we're burning. I know it hurts.

[itsybitsycoder]

No drugs. I just stopped eating certain types of foods, and started eating more of other types of foods. For a couple weeks I added up my calories consumed for kicks, and I'm eating just as much, calorie-wise, as when I was gaining weight, and some days more. Haven't changed my exercise. No real health problems either, so unless you want to make a circular argument, where you claim I'm unhealthy because the composition of my diet affects my metabolism, you are just wrong.

[dbrunsek]

Composition of food (amount of protein, carbohydrates and fat) can affect energy expenditure through TEF (thermic effect of food) but it's practically insignificant (+/- 5% of consumed energy).

I agree your metabolism is not a static thing. When starving it can adapt to as much as 30%, yet this only means you're burning less energy and you need to adjust your intake (or modulate your expenditure somehow - by exercising, not having too big of a caloric deficit etc.).

Stopping to eat certain kinds of food and/or starting to eat other kinds of food will not make you lose weight. Eating at a different time will not make you lose weight. Combining foods differently will not make you lose weight.

Weight loss is a result of a negative energy balance. Now, all these things you listed can impact your energy intake (and thus energy balance), especially if you eat calorie less dense food. But you're losing weight because you're eating less. All the things you listed are (more or less successful) ways to modulate your hunger. You're not necessarily eating less by volume, but certainly less by energy value.

Physics is clear - psychology and hunger management not so much. But I'm strictly speaking of physics and the fact that you stated that you lost weight without increasing energy expenditure or decreasing energy intake.

[itsybitsycoder]

As I've mentioned, I spent a few weeks counting my calories to see whether that was actually true or not. The fact is, I lose more weight with no exercise and a 1700-2100 calorie diet of a controlled composition, than I did running 3 days a week on a 1200-1400 calorie diet of uncontrolled composition. Nutritional science is not nearly as nailed down as you seem to think it is, and frankly the claim that our metabolic systems are magically inaffected by the types of food we choose to eat (unlike every other part of our body) comes off as more than a bit silly when you simultaneously admit that other substances can affect metabolism. I won't claim to have all the answers, but you sure as heck don't have them either.

[jacques_chester]

Calories in - calories out is often substituted for calories on food label - calories on treadmill display.

This is a categorical error that leads to people thinking that thermodynamics and the conservation of matter and energy are wrong.

The labels on food are estimates. The exercise databases are estimates. Therefore when you perform the equation with those inputs, it is approximate only.