Of course one can say basic things like "average daily calories should be between 800 and 3000", but even a range that covers 95% of the population isn't right for everyone, and isn't precise enough to really help anyone. Individuals differ not only in terms of lifestyle, which conceivably could be studied, but also in terms of genetics, which no study to date has examined in more than a rudimentary way. The various statistics sins that we complain about on HN are exacerbated when important factors like genetic background are left unstudied. And we haven't even mentioned the fact that most published (and unpublished) nutrition studies are funded by the food and supplement industries!

A rejection of a particularly poor practice of science is not a rejection of science. I doubt we'll see decent nutrition science until we're all equipped with a network of bloodstream nanobots that measures the actual physical response we each display to nutritional input.