Eating large amounts of meat and dairy products may increase the risk of prostate cancer, a new research has found.
The foods raise the levels of a hormone in the body, called Insulin like Growth Factor 1, which can spur on tumour growth, according to a new study.
To reach the conclusion, a University of Oxford team examined the results of 12 studies, featuring a total of nearly 9,000 men.
They found men with high blood levels of IGF1 were up to 40percent more likely to develop prostate cancer than those with low levels.
The study has been published in the journal Annals of Internal Medicine.
IGF1 plays a key role in the growth and development of children and adolescents. While in adults, it continues to regulate cell growth and death, but it can also inhibit the death of cells, which have come to the end of their natural life cycle.
Lead researcher Dr Andrew Roddam said the degree to which diet influenced IGF1 levels was unclear.
But he said levels could be up to 15 percent higher in people who ate a lot of meat and dairy products.
"There is a need to identify risk factors for prostate cancer, especially those which can be targeted by therapy and/or lifestyle changes," BBC quoted Dr Roddam, as saying.
"Now we know this factor is associated with the disease we can start to examine how diet and lifestyle factors can affect its levels and whether changes could reduce a man's risk," the expert added.
Dr Roddam said raised levels of IGF1 were likely not only to increase the risk of developing prostate cancer, but also to aid the spread of tumours.
Research shows that cells fed IGF1 grow much more quickly.
However, Dr Roddam said there was no evidence to suggest that measuring IGF1 levels could be used to develop a new test to screen for prostate cancer.