The increase in the obesity could lead to as many as 1500 more cancers a year in Britain by the year 2010. Cancer Research UK which carried out the survey claims that too few people are aware of the link between excess weight and the risk of developing tumors.

"I could lose a whale weight if I must do now."

Louise Diss is determined she'll never go back to the days when she weighed over 20 stone. She knew it wasn't good for her, but she had no idea her weight was putting her in great risk of developing cancer. Then, doctors found an abnormal growth in her womb. In the end, it wasn't cancer, but the scare was her spur to lose weight.

I was absolutely determined to do something about it, I've got children, I want to be live to be old and healthy. And I, I realized that I was worth more than, you know, getting ill and getting old, or getting the ill before I go old.

She's not alone, there is widespread ignorance of the cancer risks of being overweight.

After smoking, obesity is one of the biggest preventable causes of the disease.

But according to Cancer Research UK, only 29 per cent of overweight or obese people know that. They say excess weight causes 3.8 percent of all cancers. And if obesity rates keep rising, there will be 15, 00 extra cases a year by the end of the decade.

It's very worrying, because obviously these cancers are largely preventable by changes to lifestyles. So it's important that we get the message out there and encourage people to find ways to reduce their risk of cancer where they can.

But with one in four Britons now clinically obese, we are used to hearing warnings about the risks. The question is whether this one would be able to make a difference.

Jane Hughes BBC News.

NASA has set plans to start work on a permanently-occupied base on the moon. It's sown the centre could be used as a staging post for any manned mission to Mars.

James Westhead reports.