Cancer has existed for centuries and has become more threatening to humanity than in the past. Some people get cancer while others do not. Scientists have gathered the general characteristics of people diagnosed with cancer and investigated the reasons that increase the probability of cancer. As it is known, factors that increase the probability of getting any disease are called risk factors, and factors that decrease this probability are called protective factors.
While some risk factors can be avoided (such as quitting smoking, eating regularly), we cannot change some risk factors (characteristics we inherit from our family, etc.). Cancer prevention can be done by avoiding some risk factors and increasing the protective factors that reduce the possibility of cancer.
Chemical prevention (chemoprevention) is the use of substances such as drugs and vitamins to prevent the changes caused by environmental risk factors in cells and thus cancer. The main purpose of chemical prevention is to reverse the biological processes that cause cancer by using natural or synthetic substances. Therefore, it is aimed to reverse the pre-cancer or early stage disease, to prevent the disease in people at high risk, and to reduce the frequency of certain tumors. Thus, it is considered a public health initiative in societies where the risk is high.
Among the causes of cancer, environmental causes and genetic causes can be counted. Among the environmental causes, the most important factors are smoking, edible food, obesity, hormones, viruses, physical and chemical agents. It is also frequently observed in the background of cancer, chronic inflammatory events and benign tumors. Cigarette smoking, which is one of the leading causes of cancer, is one of the most important health problems for our society.
Today, many factors, including edible foods, additives to foods, sweeteners, chemicals that color foods, and the way foods are cooked, are counted among the causes of cancer. In addition to the innumerable contributions of biotechnology and the chemical industry’s entry into the food sector, it should not be overlooked that it will have such fearful effects. Although its harmful effects are not shown today, the use of genetically modified corn as feed in the livestock sector can start a public debate.
Today, in the fight against cancer, the measures taken to avoid the disease are considered more prominent. This means staying away from cancer-causing factors as much as possible, investigating the risks associated with familial cancer if there is a risk, and having regular controls for early diagnosis. The most important goal is for every individual in the society to live a healthy life away from cancer.
The first step in cancer prevention is regulation of diet.
There is no single food or food component that protects you against cancer. However, it is accepted that the inclusion of many plant-based nutrients in the daily diet together (combined) is protective against the development of cancer. Minerals, vitamins and phytochemicals in plant foods interact with each other and increase the protective effects of each other against cancer. In addition, vegetables, fruits, whole grains are low in calorie density and protect our body against weight gain. An increase in body fat is a risk factor for the development of cancer. A plant-based diet has a protective effect on the individual from the development of colorectal cancers, breast, esophagus, endometrium, pancreas and kidney cancers, which are associated with an increase in body fat ratio by preventing excessive weight gain. At least two-thirds of a meal portion should contain fruits, vegetables and grains. Many studies show that a diet rich in fruits, vegetables, grains and legumes is protective against cancer. The mechanisms by which this protective effect occurs and which nutritional components play a fundamental role are being studied intensively.
Poor diet also poses a risk for the development of cancer. The points to be considered in general are as follows:
1- Salt should not be consumed excessively and very salty foods should not be taken,
2- Diet should contain fiber and vitamins,
3-Reducing and limiting fat,
4- Consumption of foods with nitrate and nitrite added should be reduced,
5- Smoked foods should be avoided,
6- Excessively purified foods should be avoided,
7- Adjusting the ratio of saturated and unsaturated fats in lipids,
8- Overweight should be avoided.
Cancer Preventive Foods:
Pulses
Beans, lentils and peas are in this group along with many varieties. Soybeans are included in this category, their anti-cancer benefits are described in the soy section.
Active substances in legumes, saponins, protease inhibitors and phytic acid are components that have a protective effect against cancer. These compounds naturally found in plants are called phytochemicals. They protect our cells against cellular damage that causes cancer. In laboratory studies, it has been shown that compounds called saponins in legumes prevent the emergence of cancer cells and slow down tumor growth in different tissues. Protease inhibitors prevent the proliferation of cancer cells. It prevents the substance called protease secreted from cancer cells from damaging the surrounding cells. Phytic acid significantly inhibits the growth of tumor tissue. Legumes are also rich in fiber. It has a protective effect for colorectal cancers.
Strawberries
Fruits such as strawberries, blueberries, blackberries, acai, goji are in this group. They are rich in vitamin C and fiber. As foods rich in vitamin C and fiber, they have a protective effect against esophageal and colorectal cancer. All berries, especially strawberries and raspberries, are rich in ellagic acid. In laboratory studies, this phytochemical has been shown to prevent cancer of the skin, bladder, lung, esophagus, and breast. These effects are due to its antioxidant properties. It helps the body to deactivate some cancer-causing substances and to stop the cancerous process. Strawberry is also a fruit rich in a wide variety of phytochemicals called flavonoids. These flavonoids are considered to be the most effective chemicals, especially in the prevention of cancer. Blueberries are rich in anthocyanoside (anthocyanoside), which is in the group of phenolic compounds. This compound is the most powerful antioxidant known among phytochemicals.
Cruciferous
Vegetables such as cabbage, cauliflower, broccoli, brussels sprouts, white or red radish are in this group. They have a protective effect against cancer of the mouth, pharynx, larynx, esophagus, and stomach. The anti-cancer effect of cruciferous vegetables is due to the phytochemical called isothiocyanate they contain. The richest cruciferous vegetables in isothiocyanates; cabbage, curly lettuce, broccoli and especially black cabbage. In order for this substance not to deteriorate, cruciferous vegetables should be eaten as raw and fresh as possible. Isothiocyanate is produced when vegetables are chopped, chewed and digested.
In addition, glucosinolate, kramben, indole-3-carbinol substances are also found in cruciferous vegetables. It has important functions in the regulation of enzyme complexes involved in the mechanisms of protection against cancer.
Green Leafy Vegetables
Spinach, kale, lettuce, mustard greens, chicory, and chard are excellent sources of fiber and folate. They also contain lutein, zeaxanthin, carotenoids, a wide range of saponins and flavonoids. These components prevent the development of cancer by neutralizing the formation of free radicals at the cellular level. The folate contained in them has a preventive effect against the development of pancreatic cancer, and the fibers prevent the development of colorectal cancer.
Flaxseed
Flaxseed is available in the form of flaxseed meal, flaxseed meal flaxseed oil. Flaxseed is the best food source for substances called lignans. Lignans have estrogen-like effects in the body because lignans are classified as phytoestrogens. It is also rich in omega-3 fatty acid, alpha-linolenic acid (ALA). It has been shown in some studies to provide potential protection for heart disease and some types of cancer. Its effects on breast cancer are controversial.
Garlic
It is a member of the allium plant family, which includes vegetables such as garlic, onions, and leeks. The foods in this group have a protective effect especially in terms of stomach cancer. In addition, garlic reduces the risk of developing colorectal cancer. The protective effect of garlic is dose related. In other words, as the amount of consumption increases, its protective effect also increases. Vegetables belonging to the allium family, such as garlic, are rich in organosulfur compounds such as quercetin, allixin, allicin, alliin and allyl, which have a protective effect against cancer. In laboratory studies, the protective effects of diallyl disulfide, a component of garlic, against skin cancers, colon and lung cancer have been demonstrated.
Grape and Grape Juice
Polyphenols in grapes are antioxidant compounds. Antioxidants have the feature of protecting cells from oxidative damage by molecules called free radicals. Free radicals cause permanent damage to important cellular elements such as proteins, cell membrane and DNA. These harmful effects are held responsible for carcinogenesis. Polyphenols are found in many fruits and vegetables, including grapes. Polyphenols have been shown to have aromatase inhibitory effects. Peripheral estrogen synthesis is of great importance, especially in the development and maintenance of breast cancer. The most important enzyme involved in this synthesis is aromatase. Aromatase inhibitors have been used successfully in the adjuvant treatment of hormone-sensitive breast cancer and metastatic disease. Demonstrating the aromatase inhibitory effects of polyphenols in grapes is of great importance in the prevention of breast cancer development.
Green tea
Since ancient times, tea has been used as both a beverage and a medicine. Black and green tea both contain numerous active ingredients, including polyphenols and flavonoids, powerful antioxidants. Tea is the best source of catechins in the human diet, and green tea contains about three times more catechins than black tea. In laboratory studies, it has been proven that green tea completely prevents the development of cancer in colon, liver, breast and prostate cells. With regular use of green tea, the risk of bladder, colon, stomach, pancreatic and esophageal cancers is reduced.
Soybean
Scientists think that various active substances in soy, such as isoflavones, saponins, phenolic acids, phytic acid, phytosterols and protein kinase inhibitors, are protective against cancer. Soy seems to contain some components that are similar to very weak forms of the body’s natural hormones. As a result, these substances in soy can mimic the actions of these hormones under certain conditions or have the opposite effect. Due to this complex effect, it is being investigated whether soy products have a negative effect on the development of hormone-related breast and prostate cancer. Soy has been shown to inhibit the growth of various prostate cancer cells under laboratory conditions. It has also been associated with inhibition of breast cancer cells in some laboratory experiments, but this has not been demonstrated in all studies. It is generally recommended to include soy in the diet.
Tomato
Tomatoes get their red color mainly from the phytochemical called lycopene. The tendency of lycopene and related compounds in tomatoes to accumulate in prostate tissue has attracted particular interest from prostate cancer researchers.
In animal models, consumption of tomato compounds has been shown to reduce the development of prostate cancer. Lycopene is a powerful antioxidant, laboratory studies have shown its various anti-cancer potential. In laboratory studies, tomato components have been shown to inhibit the proliferation of many cancer cells, including breast, lung, and endometrial.
