There is “enough evidence that vegetables are the least cancer-causing food” Dr William G Nelson, a leading cancer researcher at Johns Hopkins University, told Today in an interview recently.
“For fruits and vegetables, the colours are the antioxidants that seem to be protective – blue in blueberries, red in chillies …
“Cauliflower, broccoli, daikon (radish), bak choy, which are more common in Asian cuisine, have these protective substances in them,” he added.
Studies have also shown that condiments, such as wasabi and Chinese mustard, offered some form of protection against carcinogens in laboratory animals which had been fed with them.
While, as Dr Nelson put it, “there’s no downside to vegetables”, red meat is something that you may want to think twice before indulging in generous amounts.
“If you look at prostate cancer/breast cancer, colorectal cancer … the risks seem to be higher when people eat in particular, red meats,” said Dr Nelson, who is Marion I Knott Professor of Oncology and Director of the Sidney Kimmel Comprehensive Cancer Centre at Johns Hopkins.
Research has suggested a link between the way red meat is prepared and cancer.
“The risk seems to be higher when people eat in particular – red meats cooked to very high temperatures or over a flame”, Dr Nelson said.
This is because carcinogens are created in food at high temperatures. Some safer food preparation methods are baking and steaming, rather than pan-frying and charbroiling, he added.
“Eating things that are extremely hot … can increase the risk of cancer. You want to avoid eating scalding food; this increases the risk of oesophagus cancer,” said Dr Nelson, who was in Singapore last week to meet local cancer researchers.
Ultimately, the key to reducing the cancer risk may lie in a simple practice – whatever food you take, have it in moderate amounts.
“If you’re eating that type of food three or four times a day, that’s not good for you,” said Dr Nelson, who is his early 50s.
Dr Nelson, whose focus of research is prostate cancer, noted that the disease is “at an epidemic level in the Western world”. And while it is “not as high in Asia”, it is increasing. “Overall, 70 to 80 per cent of cancer can be attributed to environmental lifestyle, which includes cigarette smoking and the next most common is diet,” he said.
As to the genetic element, Dr Nelson said the risk of “genetics hit around 40 per cent”. Studies have shown that Asian migrants to North America typically lose their gastric cancer risk within one generation. However, the very same group increase their risk to “Western world” cancers, such as prostate and colorectal cancer.
“The question is what did they do? It is not genetics in this case, a lot of it is lifestyle, and most people think it’s diet.”
Thus, a person who is “genetically susceptible” to cancer may have a greater risk of getting the disease due to his diet or lifestyle.
As such, “personalised treatment” for people with “personalised risk” may be the way of the future when it comes to treating cancer patients, Dr Nelson added.