Fat on the inside

But thin on the outside.

A scanning technique pioneered by British doctors has discovered that many outwardly slim people are storing up dangerous levels of fat in their bodies.

...

Prof Jimmy Bell, head of the molecular imaging group at the Medical Research Council's centre at Imperial College, London, said this hidden fat could trigger heart conditions and diabetes.

"The important message is people shouldn't be happy just because they look thin; it's not about looking fit or looking thin, it's about being healthy.

"You can look healthy, but have a lot of fat internally, which can have a detrimental effect on your health.