[galdosdi]

Even something as commonplace as chewing more carelessly will result in finding seeds in your faeces.

But what's the point of giving you more specific examples? You seem to be eager to "no true scotsman" your way out of this by labelling every example of varying calorie consumption as an exception.

Even the top article referenced in this wikipedia article admits it's based on a study of bushmen who -- surprise surprise -- were in very healthy average weight and also did tremendous physical activity. What a coincidence. But sure, keep telling yourself exercise doesn't matter and it's all about Calories In Calories Out and that the body is as trivial and simple a machine as an internal combustion engine.

[Kirby64]

> Even something as commonplace as chewing more carelessly will result in finding seeds in your faeces.

Most people’s diets do not consist of fully intact seeds, or at very least it is not a large proportion of their calories. And any processing of said seeds would give you all the calories in them. This is a trivial example to discard, since most people do not have undigested food bits consistently in their stool (unless you constantly eat corn, then maybe).

To be clear, I never said exercise is not capable of burning calories. It clearly does, however the impact is pretty muted compared to the relatively easy task of adjusting one’s intake. For people that have to do enormous physical activity or just walk a ton, they are going to burn quite a bit more calories. But your natural expenditure individually doesn’t vary that much unless you wildly change your behavior around exercise.

[galdosdi]

And my point that I've repeated over and over, is that the benefit of exercise is far broader than just merely numerically burning calories. It is in all these other beneficial effects that it can indirectly help. Focusing solely on calories in calories out is a big mistake when improving health and/or tackling obesity.