OBESITY could overtake smoking as the biggest preventable cause of cancer in women 25 years from now, a new report has suggested.

More must be done to raise awareness of the “huge public health threat” posed by obesity, Cancer Research UK said.

If current trends continue obesity-related cancers in women could account for 23,000 cases by 2035 – just 2000 shy of the number which researchers said would be caused by smoking by that year.

By 2043, excess weight could cause more cancers in women in the UK than smoking, the charity’s report concluded.

Being overweight or obese as an adult increases the risk of 13 types of cancer. Some of the most common obesity-related cancers - such as breast and womb cancers - predominantly affect women.

Professor Linda Bauld, a prevention expert at the charity, said: “The decline in smoking is a cause for celebration.

“It shows how decades of effort to raise awareness about the health risks plus strong political action including taxation, removing tobacco marketing and a ban on smoking in indoor public places, have paid off.

“But, just as there is still more to do to support people to quit smoking, we also need to act now to halt the tide of weight-related cancers and ensure this projection never becomes a reality.”

Public Health Minister Joe FitzPatrick said: "This autumn we will consult on world-leading measures to restrict promotions of junk food where they are sold, such as multi-buys, which encourage over-consumption. Consumer spending on price promotions in the UK is the highest in Europe, so it is right we take action."