The claims about "cancer-causing foods" are all over the board. So, which foods actually have a basis for causing cancer, and what are their "cancer risk levels"? To clear up the confusion, the Life Times has invited Zhong Kai, an associate researcher at the Department of Risk Communication at the National Center for Food Safety Risk Assessment, to help us see through the haze.
Carcinogens are divided into 4 levels.
Carcinogens are "bad substances" that can induce cancer in humans. Their scope includes any chemical or physical substance, as well as lifestyles and work practices, that can increase the risk of cancer in humans.
In 1965, the International Agency for Research on Cancer (IARC) began the work of identifying carcinogens and has been updating information on carcinogenic factors annually. Ultimately, it classified carcinogens into 4 levels, many of which are related to food.
Level 1
Carcinogens with a proven carcinogenic effect, such as tobacco, alcoholic beverages, aflatoxin, areca nut, and Chinese-style salted fish.
People in their daily lives might think smoking and drinking are no big deal, but over time, they can become the "culprits" of cancer.
Aflatoxin is mainly found in moldy nuts, rice, and corn. When eating these foods, it is crucial to pay attention to proper cleaning and storage.
In addition, if you drink alcohol, men should not exceed one liang (about 50g) per day, and women should not exceed 0.5 liang (about 25g).
Level 2
Substances with a higher probability of being carcinogenic, such as acrylamide, lead, and 4-methylimidazole.
The carcinogenic effect of these substances has been clearly confirmed in animal experiments, but the evidence from human studies is still relatively limited.
In daily life, if you frequently use high-temperature frying or high-temperature smoke to cook food, you have a greater chance of being exposed to acrylamide and should try to avoid it. (There is also a category of 2B carcinogens, which refers to substances with a lower probability of being carcinogenic, with insufficient evidence in both animal and human studies.)
Level 3
Carcinogens that cannot yet be classified, such as Sudan red pigment, cholesterol, caffeine, melamine, and saccharin.
For these substances, the evidence for carcinogenicity is insufficient in both animal and human studies, or the evidence is sufficient in animal experiments but clearly shows no carcinogenic effect in human studies.
Of course, this does not mean that these foods can be eaten without regard to quantity, because although they are not carcinogenic, they can pose other health risks.
Level 4
Among carcinogens, there is also a 4th level, which refers to substances for which there is no sufficient evidence in related studies to prove their carcinogenicity. There are relatively few such substances in food.
"The 'harm' of the 4 levels of carcinogens in the diet cannot be generalized," says Zhong Kai. "Level 1 and 2A carcinogens should be avoided as much as possible. There is no need to be overly anxious about 2B carcinogens. For level 3 and 4 carcinogens, there is even less to worry about, as current research has not found that they can cause cancer."
Misconceptions about carcinogenic foods
Today, with food safety concerns, people are terrified of "cancer-causing foods." Many people, upon seeing that a certain food is linked to cancer, immediately put it on their "blacklist" and stop eating it.
>Zhong Kai says that people don't need to panic about this. Having a carcinogenic risk does not mean it will definitely cause cancer.First, "dose" determines toxicity. Carcinogens in food require a long process to "poison" the body. For example, eating one rotten peanut will not immediately give you liver cancer, but if you eat fried foods and barbecue every day, over time, it will inevitably cause the body to "heat up," which is very likely to be linked to cancer.
Second, many "cancer rumors" cannot withstand scrutiny. For example, rumors like "milk causes cancer," "bringing boxed lunches causes stomach cancer," and "microwaved food causes cancer" are all caused by scientific errors. The causes of cancer are multifactorial, including genetic inheritance, unhealthy lifestyles, and more, and cannot be simply attributed to a single carcinogen.
Anti-cancer diet model: "One-Two-Three-Two"
Although there is no specific food that is definitively carcinogenic when eaten, improper eating habits can indeed increase the risk of cancer, and this is what deserves more of our attention.
Related research shows that 30% of cancers are caused by improper diet, common ones include: eating too few vegetables and fruits, unscientific cooking methods, unreasonable eating habits, and eating too many high-fat foods, all of which increase the risk of colorectal cancer, stomach cancer, lung cancer, etc.
Zhong Kai recommends that the anti-cancer diet model should be "one adequacy, two no's, three reductions, and two persistences."
One Adequacy
It refers to consuming an adequate amount of vegetables and fruits every day, eating 25 types of food, and trying to eat more whole grains and legumes.
Two No's
It means controlling yourself to not smoke and not drink, staying away from tobacco products, secondhand smoke, and alcohol.
Three Reductions
It means eating less or no processed meats, such as cured meats and canned meats, and reducing oil and salt in your daily diet.
Two Persistences
It means persisting in exercise, exercising regularly every day, maintaining a healthy weight, persisting in health check-ups, and undergoing reasonable cancer screening.