He said it was his duty to highlight issues “that can have a detrimental effect on people” (writes Grant Smith).

Mr Luke also rejected comments from the media and the public about MPs’ workloads.

He pointed out that he had recently spoken publicly about breast cancer and had visited Northern Ireland yesterday.

Mr Luke is one of 12 MPs to date to sign an early day motion attacking the show.

They say it is “discriminatory and unfair” as it judges people on their looks rather than solely on their talent as singers.

It was wrong to pressurise young people into conforming to a preconceived image, they argued.

Early day motions, which are circulated in written form among MPs, are a common way for topical issues to be raised.

They do not necessarily lead to debates in the House of Commons.

However they can be a useful way for members to put pressure on the Government or to bring an issue to public attention.

The motion criticising Pop Idol is still open and more signatures may be added.

Of those who have signed so far, half represent Scottish constituencies.

That has led to comments from some newspapers about whether or not this was a fitting subject for MPs to involve themselves in.

For example, one national newspaper said that teenagers had enough pressure in their lives without having to worry about looking like their pop heroes.

However, another said it was not a proper matter for Parliament and suggested the Scottish MPs should get a life and find some real work to do.

There have been comments along similar lines from some members of the public.

They reckoned their elected representatives ought to be dealing with more important topics than a TV show.

Mr Luke responded by explaining that he had a particular interest in the media, having spoken on the topic many times as a backbencher and had discussions with the BBC and ITV over their programmes.

He said, “I am keen to see that standards in the media are kept high.

People may think it is trivia, but TV has such a big impact on people’s lives.”

Reality TV shows such as Pop Idol had become a phenomenon in the last few years, he said and there was a growing awareness that they were set up in such a way as to provoke strong reactions from participants.

That could cause problems.

“As MPs we have a role to play in picking up issues that may have a detrimental effect on people’s lives,” he insisted.

Mr Luke added that he and his fellow Scottish MPs had important work to do on matters affecting Scotland and the whole of the UK.

A search of the list of early day motions shows that Mr Luke has added his signature to 100 of them in the past year.

Among the most recent are ones welcoming Network Rail’s decision to stop using outside contractors for track maintenance and supporting a Bill that would pave the way for a referendum to be held on joining the Euro.

He has also lent his support to criticism of airline company Easyjet for hiking fares to Holland for football fans wanting to travel to Scotland’s crucial European championship play-off.