Men who eat more than two servings of red meat cooked on a high heat are 40 percent more likely to get prostate cancer, according to a new US study.
Researchers from the University of Southern California (USC) and the Cancer Prevention Institute of California found pan-frying meat is the worst cooking method.
It appears cooking meat at high temperatures creates potent DNA-damaging carcinogens called heterocyclic amines (HCAs) and polycyclic aromatic hydrocarbons (PAHs).
HCAs form when protein is cooked at high temperatures for a long time, while PAHs form when fat from the meat drips onto an open flame, creating smoke that deposits PAHs on the meat.
The researchers examined data from almost 2000 men who answered questionnaires about their red meat and poultry intake. They were also asked to photograph their cooking methods and how charred their meat was.
More than 1000 of the participants had advanced prostate cancer.
"We found that men who ate more than 1.5 servings of pan-fried red meat per week increased their risk of advanced prostate cancer by 30 percent," said Dr Mariana Stern, associate professor of preventive medicine at the Keck School of Medicine at USC.
"In addition, men who ate more than 2.5 servings of red meat cooked at high temperatures were 40 percent more likely to have advanced prostate cancer."
Stern, whose study was published in the journal Carcinogenesis, also found eating processed meats, such as hamburgers, increased people's risk of prostate cancer.
"We speculate that these findings are a result of different levels of carcinogen accumulation found in hamburgers, given that they can attain higher internal and external temperatures faster than steak," Stern said.
The men who ate baked poultry had a lower risk of prostate cancer, however those who pan fried it had a higher risk.
"The observations from this study alone are not enough to make any health recommendations, but given the few modifiable risk factors known for prostate cancer, the understanding of dietary factors and cooking methods are of high public health relevance," Stern said.