South Africa’s favourite pastime, the old fashioned braai, may be contributing to the rise in cancer.
“Braaiing meat at high temperatures results in the formation of a group of cancer-causing substances – or carcinogens– called hetrocyclic amines (HCA), “ says Anne Till, Discovery Vitality’s nutrition advisor and registered dietician.
“Food carcinogens contribute to cancer by causing different types of DNA damage to the mouth, throat, stomach and other organs related to the digestive system, such as the liver,” explains Till.
Studies link cooked meat and cancer
Recent studies done by the US’s National Cancer Institute have found a link between cooked meats and stomach cancer. The study evaluated the cooking habits of 176 people diagnosed with stomach cancer and 503 people without cancer.
The research revealed that people who ate well-done meat were three times more likely to develop stomach cancer than those who preferred their meat rare or medium rare. The study also discovered that the frequent consumption of cooked meat doubled the risk of developing stomach cancer.
Braaiing is particularly harmful, because it generates carcinogens in two ways:
- Cooking meat at high temperatures forms HCA’s
- Exposing the meat to smoke at the same time forms other carcinogens, called polycyclic aromatic hydrocarbons.
Temperature is important factor
“HCA’s can be present in the human diet in substantial concentrations depending on cooking habits,” says Till. “They develop when the high heat, used during braaiing or searing, breaks down an amino acid (creatinine) found in meat.”
Temperature is the most important factor in forming these particular carcinogens, but how long the meat is on the braai and how close it is to the open flame, can also play a role.
There are a number of ways to reduce the level of carcinogens, says Till. “Precooking meat in a non-plastic container in a microwave or oven for a few minutes significantly lowers the amount of HCA’s formed.” Research suggests that cooking in a microwave before braaiing decreases HCA’s by as much as 90%.
She also suggests :
- Cooking smaller portions of meat, which shortens the cooking time
- Avoiding the blackened and burnt parts, and
- Eating smaller portions.
Eat fruit and try different cooking methods
“Furthermore, a daily intake of fresh fruit and vegetables (five to nine servings daily) may reduce the risk of certain types of cancer and certainly improves your overall health,” Till advises.
She points out that, “There are other ways of preparing meat that use lower temperatures and do not contribute to the formation of HCA’s – such as roasting, stewing, microwaving, braising, boiling or poaching.”
Other carcinogens to be aware of include chemicals used to preserve meat and environmental chemicals like dioxins, which build up in the fat tissue of animals and humans. “Exposure to carcinogens should be minimised wherever possible,” Till warns. “One can reduce your exposure by removing fatty skin and fat from meat, fatty fish and poultry before cooking”.
“Although there are still some questions, there is sufficient evidence to suggest that dietary factors play an important role in causing cancer,” she says. While food carcinogens still have a smaller role in the development of cancer when viewed against other risk factors, it is still sensible to be informed and avoid foods known to have high levels of carcinogens. - (Press release from Discovery Health, August 2007)
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