[mavhc]

Problem is you only know the max potential input, not the actual input, which depends on your gut bacteria.

And also you're not directly measuring the output, which is different for everyone, and adjusts based on the input.

It's useful for making you think about everything you eat though, shall I eat this thing? Well, I'd have to record it in my spreadsheet, won't bother.

[jjoonathan]

Direct control over an upper bound is quite sufficient to force a number downwards. All of the error terms point in the direction of undereating when the problem is overeating.

The real problem with calorie counting is that it is difficult.

[makeitdouble]

You aren’t even controlling the upper bound, because as explained these calories have not much to do with how your body processes them. For instance you might think you reduced the calorie count by forgoing 200 calories of bread to eat 150 calories of tofu, but if your body processes tofu better than bread, you’ve effectively increased your energy consumption while the count is lower on your spreadsheet.

Same way you might be eating the same amount of tofu everyday, assuming you have a steady calorie intake, while your actual ingestion rate will be all over the board. If/when you’ll be decreasing quantities your ingestion rate might go up enough to effectively increase the energy you take from it, creating weird states that don’t make any sense looking at the numbers from outside.

The lowering the upper bound only start to make sense when the body is really starving, in that your daily life has become hell, and you start lacking elements other than calorie. Some see that as a success, I see it as dangerous for most people.

The people dropping out of these diet don’t do so because they don’t have the guts, but because they end up worse that where they were at the beginning. It’s not everyone ending up there, so we’ll still hear the success stories of course.

[adrianN]

Generally you not only count potential calories, but also measure you weight. You can then adjust calories up or down to keep hitting your targets as your body and your activity levels change.