Fat may or may not be a feminist issue, but at Westminster these days it is certainly a political one.

Not only is obesity important in itself - it threatens to overtake smoking as the nation's biggest killer - but the topic is one that hits all the right political notes. As a result obesity, not long ago way off the political radar, is being discussed enthusiastically in New Labour circles.

It was a notable talking point at Labour's autumn conference, and MPs on the health select committee have joined in after beginning their inquiry in June.

The reason is partly straightforward: Britain is catching up with the US as a fast-food addicted overweight nation, and the health and economic implications are alarming.

But it has also attracted attention because it stands out as something different in the current political climate.

Non-confrontational and cross-departmental, the issue draws in everyone from the department of health and the treasury to media regulators.

It has also interested policy makers eager for serious issues outside the tit-for-tat of Westminster.

There is another reason why obesity crops up more and more in political debate: there is money in it. The food and health industries have huge buying power and plenty of smart, articulate lobbyists.

The food industry is terrified of the sort of restrictions that have long been imposed on smoking, and that is exactly what the health professionals want.