Types Of Cancer

ARE barbecued beef, fried chicken and other charcoal-roasted or grilled meats your favorite foods? If so, beware. According to the US National Cancer Institute (NCI), fried and barbecued meats contain mutagens (chemicals that may damage the DNA) and carcinogens (compounds shows to cause cancer) such as heterocyclic amines (HCAs) and polycyclic aromatic hydrocarbons (PAHs).

How the chemicals form

HCAs are formed when amino acids (the building blocks of all proteins) and creatine (a chemical found in muscles) react at cooking temperatures. They are created in greater quantities when meats are cooked at high temperatures.

PAHs are formed by burning fat during open flame cooking. The smoke resulting from the burnt fat contains PAHs that are deposited on the surface of the meat.

In beef, pork, fowl and fish

Research conducted by the NCI, as well as by Japanese and European scientists, has identified at least 17 HCAs that result from the cooking of muscle meats such as beef, pork, fowl and fish. And western food lovers take note. About half of the HCAs identified were found to be present in foods Americans eat most often!

Cancer in animals

In animal studies, mice, rats and monkeys fed HCAs in their diet had increased rates of certain cancers. The most abundant HCAs in cooked muscle meats. PhIP causes lymphomas (cancer of the lymph system) in mice as well as mammary and large intestine tumours in rats. Another HCA (known as IQ) was found to cause liver cancer in the majority of monkeys to which it was fed. Both PhIP and IQ (which were absorbed into the monkeys’ bodies) have also been found to alter the structure of the DNA. (This is however, nothing new as HCAs have long been found to be mutagenic, i.e. since the 1980s.)

Potential cancer risk to humans

These research results have raised concerns that HCAs may also be human carcinogens. This is compounded by the results of another different study – in which human volunteers ate 320 grams (about 10 ounces) of cooked ground meat patties – which show that most of the HCAs eaten were absorbed into the body.

(In animal studies, most of the cancer-causing chemicals from meat eaten were found to be absorbed into the animals’ bodies, where they were activated into cancer-causing chemicals, with only a small percentage excreted unchanged).

Risky high-temperature cooking

Four factors influence HCA formation: type of food, cooking method, temperature and time. Of the 4, temperature is the most important factor. According to the NCI, frying, broiling and barbecuing produce the largest amounts of HCAs because the meats are cooked at very high temperatures (over 212°F or 100°C).

“Well done” meat linked to stomach cancer

In another NCI study which assessed the diets and cooking habits of 176 people diagnosed with stomach cancer and 503 people without cancer, it was found that people who:
ate their beef “medium well” or “well done” had more than 3 times the risk of stomach cancer than those who ate their beef “rare” or “medium rare”.
ate beef 4 or more times a week had more than twice the risk of stomach cancer than those who ate beef lass frequently.

Hamburgers and lymph node cancer

According to a report published in the Journal of the American Medical Association in April last year, a study of 35,000 older women shows that those with diets high in meat and animal fat, especially hamburgers, have double the risk for lymph node cancer – also known as non-Hodgkin’s lymphoma. Researchers believe that it may be related to the way the hamburgers are cooked.

Avoid Meat

Traditional wisdom decrees that one should always cook meat thoroughly to kill any food poisoning bacteria that may be present. But this recent study has indicated that cooking meat thoroughly can lead to cancer.

Eating meat is thus a case of between the devil and the deep blue sea! Not only that, meat consumption can also result in high medical bills, as was the case in the US.

According to a 1995 report in Preventive Medicine by a doctors group, Americans spend between US$28.6 billion (now worth about RM 109 billion) and US$61.4 billion (now worth about RM233 billion) a year in medical costs for treatment of hypertension, heart disease, cancer and other illnesses attributed to meat consumption. (The report also says that eating meat is comparable to smoking tobacco and the health threat is “of a similar magnitude when you keep it up over a lifetime”.)

With all these evidence, some of you might want to avoid meat completely. If so, take heart. You can still get protein from other food sources like beans and bean products, tofu, tempeh, lentils, seed and nuts.

And here’s another consolation: Study after study have confirmed that vegetarians are healthier than meat-eaters. So why not start today?

Safer cooking methods

If you must eat meat, the NCI advises that you adopt less risky cooking methods.

According to the NCI:

• Oven roasting and baking are relatively safer than frying or barbecuing as they are done at lower temperatures.

• Stewing, boiling or poaching are done at or below 212°F, which is also quite safe.    If possible, avoid making gravy from meat drippings.