The most surprising outcome of the study is that less than 2 servings per week will increase cancer risk. “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 per cent,” said research team leader Mariana Stern at the Keck School of Medicine, University of Southern California.
“In addition, men who ate more than 2.5 servings of red meat cooked at high temperatures (per week) were 40 per cent more likely to have advanced prostate cancer,” added Stern, the journal Carcinogenesis reports.
Frying meat on a gas burner may be more harmful to health than using an electric burner, because of the type of fumes it produces.
Professional chefs and cooks may be particularly at risk. If you enjoy pan seared meat and restaurants, the method is commonly used to attract a specific clientelle who enjoy the flavor.
Cooking fumes produced during high temperature frying have recently been classified as “probably carcinogenic” by the International Agency for Research on Cancer (IARC).
One research team simulated the conditions found in a typical Western European restaurant kitchen, frying 17 pieces of steak, weighing 400 g each, for 15 minutes.
Potentially harmful polycyclic aromatic hydrocarbons or PAHs for short, heterocyclic amines, and higher and mutagenic aldehydes, along with fine and ultrafine particles, have all been found in cooking fumes, using vegetable oils, such as safflower, soya bean, and rapeseed oils, as well as lard.
Napthalene — a banned chemical contained in traditional mothballs — was the only PAH detected and ranged from 0.15 to 0.27 ug/m3 air in 16 of the 17 meat samples. The highest levels were produced when frying with margarine on the gas burner.
Higher aldehydes were produced during the frying of all the samples, while mutagenic aldehydes were produced for most samples.
Overall levels ranged from undetectable to 61.80 ug/m3 air, but the highest levels were found when frying on the gas burner, irrespective of the type of fat used.
The peak number of ultrafine particles during frying on the gas burner was considerably higher than when cooking with electricity. Particle size with gas was 40 to 60 nm compared with 80 to 100 nm with electricity. Ultrafine particles are more readily absorbed into the lung.
Attention to cooking methods of red meats, shows the risk of prostate cancer may be a result of potent chemical carcinogens formed when meats are cooked at high temperatures, especially on gas stove.
Information regarding cooking practices (pan-frying, oven-broiling and grilling) is typically obtained using specialized colour photographs that display the temperature achieved by each cooking process.
Although there other factors may have been involved, such as lifestyle and poor dietary habits, the University of Southern California report found a correlation between pan-fried red meat and disease in more than 1,000 of the men included in the study who were diagnosed with advanced prostate cancer.
The problem is not only confined to red meat. Heterocyclic amines (HCAs) can form when any muscle meats, including, pork, poultry or fish, are cooked at high temperatures. They are products of interaction between amino acids, which are the foundation of proteins, and the chemical creatine, which is stored in muscles. Past research has identified 17 HCAs that may contribute to cancer.
To take the investigation a step further, some researchers have even analyzed each DNA to find if it contained genetic variants in the HCA metabolism pathways that may interact with red meat intake to increase the risk of cancer.
People with seven or more unfavorable genotypes as well as high red-meat intake were at almost five times the risk of cancer.
“This research reinforces the relationship between diet and cancer,” said Xifeng Wu, M.D., Ph.D., professor in M. D. Anderson’s Department of Epidemiology and lead author on one study. “These results strongly support what we suspected: people, who eat a lot of red meat, particularly well-done red meat, such as fried or barbecued, seem to have a higher likelihood of cancer. This effect is compounded if they carry high unfavorable genotypes in the HCA-metabolism pathway.”
A solution? Adding a dash of rosemary extract to beef appears to reduce the amount of cancer-causing compounds created during the cooking process. nvestigators found that when they added antioxidants extracted from rosemary to ground beef, the hamburgers contained smaller amounts of heterocyclic amines, or HCAs, carcinogenic compounds that form when muscle meats like beef, pork and poultry are cooked at high temperatures.
They certainly doesn’t remove all the risks of consuming meat cooked at higher temperatures, but for those who insist on such dietary habits, keep a little rosemary on hand along with oregano, sage and basil to create an antioxidant cocktail to reduce cancer-causing compounds.