Its effect is incredible! It doubles the risk… This is the reason for 95 percent of the cases! Why do some foods trigger cancer?
Today, cancer is one of the leading chronic diseases that cause deaths. When it comes to cancer predisposition, a person’s genetic structure is also important, of course, but recent studies have shown that we can prevent almost one in every two cancers. In this context, nutrition is especially critical. So what determines which foods increase cancer predisposition and which ones are cancer fighters?
Why do some people develop cancer while others do not?
There is no single answer to this question. Some people are born unlucky and are more prone to cancer due to the genes they inherit from their ancestors. In some people, a random mutation that occurs during the body’s self-renewal process triggers cancer. When we consider that approximately 330 billion cells are renewed in our bodies every day, it becomes clearer how high the probability of such a mutation is.
However, the number of scientists who argue that the main factor in the development of cancer is how we live is increasing day by day. What we eat and drink, whether we exercise, whether we use tobacco products or whether we are exposed to environmental factors play an important role.
For example, a study published in the US last year tracked the daily habits of 2 million people for more than 20 years; it was found that approximately 45 percent of cancer cases are caused by lifestyle and are completely preventable.
Dr Sarah Blagden, lecturer in medical oncology at Oxford University, told the Daily Mail: “We now know that cancer develops long before symptoms appear or signs are detectable in blood tests. This can be 20-30 years for bowel cancer and decades for cancers such as pancreas and lung.”
“Regardless of the type of cancer, the progression from a mutation in a cell to a tumor is a long and not always linear progression,” said Prof. Dr. Marc Gunter, head of the department of cancer epidemiology and prevention at Imperial College London.
Gunter, who stated that 5 to 10 percent of cancers are caused by problematic genes inherited from ancestors, said, “But approximately 95 percent of cancers are caused by mutations that occur at some point in life, and many factors can play a role in this process. Even if a person has a gene that makes them prone to cancer, the development of cancer is not inevitable. It is never too late to adopt a healthier lifestyle to prevent the development of cancer. You can increase or decrease your chances with your lifestyle.”
Blagden agreed, saying, “Positive daily living habits can add up over the years and dramatically reduce your risk of developing cancer.”
These habits include combating obesity, which is among the risk factors for 18 different cancers, according to a study conducted by the World Cancer Research Fund in 2023.
WHAT SHOULD WE EAT, WHICH FOODS SHOULD WE AVOID?
Nutrition plays a very important role in the development of cancer in the long term. So what should come to mind when we talk about foods that trigger and prevent cancer?
EAT MORE OF THESE
Cruciferous vegetables: Vegetables like broccoli, cauliflower, kale, cabbage, asparagus and bok choy are rich in phytochemicals, which are protective compounds that prevent toxins like nitrates found in processed meats from turning into carcinogens that damage DNA in cells and trigger inflammation.
Dr Robert Thomas, consultant oncologist and sports and nutritional medicine specialist at the University of Bedfordshire, said: “Cruciferous vegetables are also a good source of sulforaphane, a compound that increases liver enzymes that help break down carcinogens absorbed in the gut.”
Eating five servings of these vegetables a week reduces the risk of lung, colon and pancreatic cancers, according to a study published last year in the journal Nutrition Reviews, which evaluated 226 studies.
Nuts: Nuts also have cancer-fighting properties. These foods improve intestinal health and also increase antioxidant enzymes and help repair DNA damage.
For example, many studies show that eating walnuts regularly reduces the risk of developing breast cancer and recurrence of colon cancer.
Onions, garlic, leeks: These three vegetables are rich in quercetin, a plant compound that fights cancer. Regular consumption of onions, garlic, and leeks reduces the risk of lung, esophageal , and pancreatic cancer.
Dietitian and cancer care specialist Jane Clarke said it is better to consume these vegetables cooked because the cell walls soften under the effect of heat and the amount of beneficial compounds released increases.
Forest fruits: Whether fresh or frozen, forest fruits directly increase our melatonin levels. Stating that melatonin is an important substance in the body’s sleep-wake balance, Thomas said, “Regular consumption can improve sleep quality.”
Forest fruits are also rich in protective phytochemicals and anthocyanins, the plant pigments that give these fruits their color, and their anti-inflammatory properties help protect against cancer.
Thomas recommended eating a handful of berries 4-5 times a week.
Olive oil: Olives are rich in lignans, a powerful plant compound. Studies have shown that lignans can weaken the HER2 gene, which is associated with aggressive breast cancer. But that’s not all. Extra virgin olive oil, in particular, is rich in omega-9s. An unsaturated fat, omega-9s also help reduce chronic inflammation associated with cancer, Thomas said.
Eating at least half a tablespoon of olive oil every day can reduce the risk of death from cancer by 17 percent, according to a 2022 study conducted by Harvard University’s TH Chan School of Public Health.
Carrots: Carrots are rich in beta carotene and vitamins A and K. Studies show that these substances reduce the risk of various cancers.
For example, according to a 2023 study published in the journal Nutrients, people who ate more than 32 grams of carrots per day (half a medium carrot) were 17 percent less likely to develop colorectal cancer.
Citrus fruits: Rich in vitamin C and bioflavonoids, a type of plant compound that protects cells, citrus fruits have been shown to prevent many cancers, including pancreatic, prostate, and stomach. A 2008 review published in the journal Gastric Cancer found that eating three servings of citrus fruits per week reduced the risk of stomach cancer by 28 percent.
Legumes and whole grains: “These foods are also rich sources of lignans and another type of compound called isoflavones,” Thomas said, noting that isoflavones have been associated with a lower risk of hormone-sensitive cancers such as breast and ovarian.
Legumes and whole grains also contain phytoestrogens, which partially block estrogen receptors and protect tissues from toxins such as plastics and exhaust fumes that mimic the effects of estrogen. Societies where these foods are consumed more often also have a lower risk of these types of cancers.
The high amount of fiber found in these foods also protects against cancer. One study found that every 10 grams of dietary fiber consumed from whole grains reduced the risk of developing colorectal cancer by 7 percent.
REDUCE THESE
Processed meats and red meat: There are studies showing that processed meat products such as sausage, salami, and pepperoni increase the risk of bowel and stomach cancer.
This is thought to be due to the nitrate and nitrite content found in these foods, which turn into N-nitroso compounds (NOCs) and cause damage to the cells lining the inner surface of the intestine.
According to the World Health Organization (WHO), consuming 50 grams of processed meat per day increases the risk of colorectal cancer by 18 percent.
On the other hand, according to WHO, consuming 100 grams of red meat per day increases the risk of colorectal cancer by 17 percent. This is because the heme compound found in red meat, which contains iron, breaks down in the intestines and forms NOC.
What’s more, meat fat contains dioxins, environmental chemicals that damage the immune system, disrupt hormones and have the potential to cause cancer.
Ultra-processed foods: These foods have been linked to various types of cancer, in part because they lead to obesity, which is one of the biggest risk factors for cancer. For example, a 2023 study found that a 10 percent increase in ultra-processed food consumption was associated with a 19 percent increase in ovarian cancer risk.
Refined sugar: Studies show that people who consume a lot of refined sugar have a higher risk of breast, endometrial and colon cancer.
For example, a 2014 study found that women who consumed more than 61 grams (15 tablespoons) of added sugar per day had twice the risk of developing breast cancer as women who consumed half that amount. Consuming too much refined sugar leads to weight gain, insulin resistance, and chronic inflammation, all of which are factors that increase cancer risk.
“Processed sugar has the potential to wreak havoc on the gut because it supports the growth of bacteria that trigger inflammation. Inflammation, a major driver of cancer, causes cells to divide very quickly. This increases the risk of spontaneous mutations and limits the time cells have to repair themselves,” Thomas said.
THINK TWICE WHEN FRYING
The foods you consume, as well as the way you prepare them, affect your cancer risk.
Cooking meat, especially processed meat, at high temperatures (frying, roasting and barbecuing means applying temperatures between 50-300 degrees) causes the formation of compounds called heterocyclic amines (HCAs) and polycyclic aromatic hydrocarbons (PAHs). These substances are associated with DNA mutations and an increased risk of colon, pancreatic and prostate cancer. ( HCAs are released when all types of animal protein, including fish , are cooked at high temperatures.)
Smoke itself is a carcinogen and can affect foods that are barbecued, grilled or cooked in oil.
Baking starchy foods like potato chips or foods with added processed sugars, such as breakfast cereals, baked at 120 degrees Celsius or above for more than three minutes also releases a toxic chemical called acrylamide, which has been linked to DNA damage and increased risk of cancer .
So what should we do?
“Steaming, cooking in water or in its own juices, or wet heat methods, produce fewer HCAs and PAHs. Or you can opt for pot roasts cooked at lower temperatures for longer periods of time. Barbecuing should only be an occasional treat,” Thomas said.
Aidan Goggins, a pharmacist who specializes in the relationship between nutrition and diseases, gave the advice of marinating meat with various herbs and said, “The cancer-preventing properties of herbs will help balance the negative effects of cooked meat.”