Seventy-five percent of people in the UK are unaware that there is a link between obesity and cancer, according to a new report by Cancer Research UK.

The survey also showed that more than three-quarters (78 percent) of those asked didn't know obesity is linked specifically to ovarian cancer, while 69 percent weren't aware of the link with breast cancer and 53 percent pancreatic cancer.

Awareness of the link with bowel cancer slightly better, at 60 percent, and liver cancer, at 55 percent, according to the report.

The findings are cause for concern because, as the charity notes, being overweight or obese is the single biggest preventable cause of cancer after smoking and is linked to an estimated 18,100 cancer cases each year in the UK.

A recent report by CR UK and the UK Health Forum estimated that, if current weight trends continue, there will be a further 670,000 cancer cases over the next 20 years.

"Cancer isn't at the forefront of people's minds when talking about obesity and that's really concerning. Few understand that excess weight increases the risk of several cancers, including some of the most common such as breast cancer," said CR UK's director of prevention, Alison Cox.

"It's the Government's responsibility to inform the public of the link and also to take action to tackle the obesity epidemic, starting with the health of the nation's children. It's great the Government's childhood obesity plan includes a sugary drinks tax, but it's not enough to curb the rising tide of ill-health," she added.

The government recently launched its long-awaited strategy to tackle childhood obesity, but the plans have received a rather luke-warm reception, largely because they stopped short of introducing curbs on junk food advertising and multi-buy promotions.

The NHS in England already spends more than £5 billion a year on overweight and obesity-related ill-health.