Well, I'm torn. I don't feel like I have the data to question the figure of 12-15 million extra, but at the same time, living here outside of London & SE, it doesn't seem impossible, if most of them are in the SE.

Did these food analyses account for the ongoing trend for everyone to eat enough for two? Obesity is a real thing...

Around here we've had clearly noticeable immigration. Population levels are, I would estimate anecdotally, back to pre-miner's strike (and steel and textile industry collapse) levels. For Yorkshire that suggests the population has bounced back up by half a million.

Now obviously, not all of those are from outside the UK, but a large majority are.

All the same, replicate that across the country and you only get 7-10 million increase, unless we assume (maybe not unreasonably) that Manchester, Birmingham and London/SE have had a much larger proportionate increase.

And the 60 million figure is the 2001 Census one, which doesn't include social support system info or even labour force survey info.

So, I guess I'm saying:

a) It does look possible.
b) I'm not sure that they are all "between the cracks" of society, so much as that the 60 million figure was known to be worrisome in 2001. There was the whole "1 million missing young men" (of whom I was one.) and numerous other issues.

BUT even if we say pop is 70 mil, with 7 mil "shadow pop" that is 10%, which is incredibly scary now I stop and think about it. 10% of the population...

Welcome to the Anglo disease...