This is a question which has been niggling me for ages, but I'm finally prompted to ask it by the numbers in this BBC news story:
How many calories should you eat? 2,500 calories for men daily 2,000 calories for women daily 1,800 calories for children aged five to 10 daily Source: NHS
(And indeed it's easy enough to find this info on the NHS site too). Now I'm pretty sure a decade or two ago you'd read the nutritional information on the side of packages and it would recommend 2000 for men and 1800 for women, and then at some point it seemed to creep up to 2200 for men and 2000 to women. And now I'm really surprised to see 2500 suddenly. Certainly the government can and does change these numbers (and the above may even be out of date!): see this article.
I also vaguely remember seeing some comments (either in or associated with the TV programme "The Men Who Made Us Fat" or some commentary/review/blogging associated with the book "Why Calories Count: From Science to Politics") claiming that the food industry has an obvious interest in seeing such numbers pushed upwards and actively lobby for such. But it's harder to find any concrete evidence for this; of course it's also hard to find anything which gives me any confidence the numbers are arrived at by a transparent process.
Update; subsequent finds:
- There is some history on the old "2000" number here which implies it was already considered to be too low when it was introduced.
- NHS has information on the recent increases in the UK recommendations here.
- The SACN report which lead to those increases can be referenced can be found here (228 pages!).
Anyway I think it's clear recommended calorie allowances certainly have increased and that part of the question is answered well enough; but the extent to which increases may have been influenced by industry/politics remains opaque.
(Actually, some responses to the first draft of the SACN report can be seen here and there's only one obvious industry response from the "Sugar Bureau" in it; of course at that point the draft report was out and "the industry" was probably quite happy to see a proposed increase! I note also a response from "Safefood" who "expressed concern about... the seemingly paradoxical message of increased energy requirements for many population groups in the face of an obesity crisis"!)