To those of us who read the New Scientist this is old news.

There is a scientist who can prove it by statistics. Yea, quite. His theory is not universally accepted but he is almost arrogant in his assertions.

The only problem I have with the stats is that all too often two seemingly linked phenomena like the prevalence of the antibodies to a specific virus and obesity can sometimes be chance and more often is linked by a common cause but neither are the cause - only the effect of the as yet unidentified stimulus.

But the guy is probably on to something. AND it doesn't cause obesity - it pre-disposes people. Like being tall gets you noticed in a crowd. The rest is down to - well you've heard it all before.