New US research suggests emulsifiers commonly used in processed foods may trigger colon cancer and may be to blame for the increase in incidence of the disease.

A common food additive used to extend shelf life promotes the growth of colon cancer in mice, according to a new study.

Emulsifiers are added to most processed foods to aid texture and keep them fresh but the findings of the US study, published in journal Cancer Research, suggests they are toxic to the body and potentially deadly.

Researchers at Georgia State University found regular consumption of dietary emulsifiers in mice exacerbated tumour development.

It's believed the emulsifiers alter the microbiota inside the intestines to create the ideal conditions for cancer growth.

The team of researchers fed mice with two very commonly used emulsifiers, polysorbate 80 and carboxymethylcellulose.

They observed that consuming the emulsifiers drastically changed the composition of the gut microbiota in a manner that made it more inflamed.

This change in the intestinal microbiota enhanced tumour development.

Dr Emilie Viennois, who led the study, says the findings support the belief that environmental factors have played a pivotal role in the dramatic increase in the incidence of colorectal cancer.

"The incidence of colorectal cancer has been markedly increasing since the mid-20th century," said Dr Viennois.

"A key feature of this disease is the presence of an altered intestinal microbiota that creates a favourable niche for tumorigenesis," he said.

In Australia, bowel cancer is the second most common cancer in both men and women and is more common in people over the age of 50.

Bowel cancer, also known as colorectal cancer, develops from the inner lining of the bowel and is preceded by growths called polyps, which may become invasive cancer if undetected.

The risk of being diagnosed by age 85 is 1 in 11 for men and 1 in 15 for women.

It is the country's second biggest cancer killer, second to lung cancer, with more than 4000 deaths in 2013.