Are you a non-smoker but addicted to junk grub? Beware!

Fast food can lead to obesity which has become the main cause of cancer, particularly in people who don't puff fags.

Yes, according to a study by researchers in Britain, though smoking is still the single biggest cause of cancers, obesity is claiming lives of a number of non-smokers every year, The Daily Telegraph reported on Saturday.

"Already the majority of people don't smoke and for them obesity may be the most important identified cause of cancer. Eating a balanced diet is important to maintain a healthy weight," lead researcher Professor Tim Key of Cancer Research-UK was quoted as saying.

According to the study, obesity increases the risk of breast cancer in women by raising the level of hormones such as estrogen; it also raises the chance of bowel cancer, particularly in overweight men.

Moreover, the researchers have found that obesity is also a major cause of kidney cancer and it has also been linked to other rarer cancers.

In fact, they came to the conclusion after spending over five years collecting data about the effect of bodyweight, diet and physical activity on the risk of developing cancers.

The study has been endorsed and funded by the World Cancer Research Fund and will be published in the form of a report, titled Food, Nutrition, Physical Activity and the Prevention of Cancer: A Global Perspective, at an international conference at The Royal Society in London [Images] next month.