[carbocation]

The "science" behind this is a randomized, controlled trial. Why the scare quotes?

[WilliamLP]

For one thing, though scientific, any conclusion is going to be rather soft if it's drawn from one study where human beings self-report calories, and where the difference in weight (2kg) is within the variance of how much our weight can vary within a single day.

[jules]

Heck, if I go cycling in the morning and don't drink enough I can be 4kg heavier after dinner that day than right after cycling.

[carbocation]

Heh, I agree with you. Sadly those concerns would also be valid for many other RCTs!

[whatusername]

because controlled trials that involve large groups of people are very difficult to actually control.