In spite of the most advanced medicines as well as medical technology cancer still continues as a severe threat to humanity and even in the most developed countries fatality among cancer patients has increased to alarming levels. In the US alone, about 1.5 million people are affected by cancer every year and every year more than 500000 people die there because of cancer. According to reports from American Cancer Society, wrong diet contributes to cancer in many cancer diagnoses. The World Cancer Research Fund (WCRF) and American Institute of Cancer Research (AICR) have highlighted the importance of proper food and nutrition also in their recommendations for cancer prevention and their recommendations were based on the studies conducted by a group of scientists from different countries and their studies were about the link between cancer risk, food and physical activity. About 35% of Americans are likely to get affected by cancer mainly because of improper dietary habits and also smoking.
Plant foods in general and fruits and vegetables in particular are rich sources of micronutrients like carotenoids and flavonoids. These micronutrients are powerful antioxidants which can protect the cells from the effects of harmful oxidation reactions which are caused by biological processes. Inflammation can facilitate development of cancer to considerable extent and the plant based micronutrients such as carotenoids and flavonoids can effectively reduce inflammation. Just like healthy cells, the cancer cells also require nutrients. The nutrients are supplied to the cancer cells through a newly created network of very small blood vessels. The formation as well as growth of this type of new blood vessels is caused by cancer and this process which is initiated by cancer is called angiogenesis. The various nutrients that are present in plant-based foods including fruits and vegetables effectively prevent angiogenesis. Hence, in order to prevent cancer it is very important to follow a diet system in which a wide range of fruits and vegetables are included. The highly recommended fruits and vegetables include berries, apples, papaya, pomegranate, pumpkin, broccoli, cauliflower, broccoli sprouts, garlic, red onions and leafy greens. Parsley, tomatoes and tomato puree are good for prevention of prostate cancer.
The plant chemicals that are present in broccoli, cauliflower and cabbage convert the bad oestrogens into good oestrogens and thereby reduce the risk of cancer. These chemicals also reduce the risk of a relapse. Asparagus and Brussel sprouts are also rich in antioxidants. In most of the cases the micronutrients in fruits and vegetables are present in the skin and hence it is recommended to consume the whole fruit/vegetable as far as possible. It is to be ensured that a major portion of the diet includes fruits, vegetables and whole grains. Plant-based foods can considerably lower the risk of colon, stomach, lung, esophageal and oral cancer. Many types of cancer can be prevented by consuming more plant proteins and less animal proteins. While the plant foods are low in fat as well as calories, they are rich in antioxidants as well as phytochemicals all of which effectively reduce cancer risk. Antioxidants that are present in fruits and vegetables include beta-carotene, vitamin C and lycopene. Hence the diet that is rich in fruits and vegetables will certainly reduce the risk of cancer. It is recommended that there should be 7 – 9 servings of fruits and vegetables daily and also every day one has to eat three different colours of fruits and vegetables. The bioactive ingredients that are present in the pigments of the fruits and vegetables also have cancer preventing characteristics.
It is to be mentioned here that the spice called cinnamon, beverages like fruit juice, tea, coffee and wine and fish, shellfish and dairy products also prevent angiogenesis. The proteins in fish, shellfish and dairy products have anti-cancerous properties. Fish and soy foods are highly recommended for prevention of prostate cancer. The other proteins-rich foods that can prevent cancer include lean meat, poultry, eggs, tauhu, taukwa, nuts, dried beans, chickpeas and dhals.
While fruits and vegetables in general are rich in fiber, lentils, peas, beans, whole grains, carrots, turnips, bananas, kiwi, peaches, mangoes, pears and strawberries can provide sufficient quantities of dietary fiber. Smooth and fast movement of food through the digestive track is facilitated by dietary fiber and as a result the carcinogens and estrogens are completely destroyed. High levels of carcinogens and estrogens will increase the risk of breast cancer.
1. Fish contains Omega-3 fatty acids and vitamin D, both of which protect from cancer.
2. Garlic contains the compound known as allicin which will reduce the risk of prostate, stomach and colorectal cancers.
3. Risk of prostate cancer can be reduced by consuming tomatoes since they contain the compound known as lycopene.
4. Flaxseed reduces the risk of breast and prostate cancer.
5. Regular intake of citrus fruits like lemons, limes, oranges and grapefruits can prevent cancer.
6. Curcumin, a chemical which is present in Turmeric can prevent many types of cancer.
7. Higher intake of olive oil can reduce the risk of cancer.
8. Brazil nuts and walnuts reduce the risk of cancer.
9. Cinnamon extract has anti-cancer properties.
10. The various compounds present in berries can prevent various types of cancer.
11. Beans can reduce the risk of colon cancer and colorectal tumors.
12. Carrots can decrease the risk of stomach, lung and prostate cancer.
13. Broccoli contains the compound known as sulforaphane which can eliminate the tumor cells.
14. By taking vitamin D supplements the risk of breast, colon and pancreatic cancers can be reduced.
Obesity is one of the main reasons for cancer. It is advisable to eat slowly and also eat small portion sizes more number of times. Overeating will add too much weight to the body and ultimately it will lead to obesity. Excess weight of the body will increase the risk of cancer by 50% for endometrical cancer as well as esophageal adenocarcenoma. Postmenopausal women who are overweight will be more prone to breast cancer. Obesity increases the risk of cancer of the following parts of the body: Uterus, Prostate, Colon, Gallbladder, Liver, Kidney, Thyroid, Rectum, Pancreas and Ovaries. Foods like artificially sweetened beverages, desserts and processed snacks provide only very few nutrients but too much of calories. In order to prevent cancer it is very important to avoid or at least considerably reduce the intake of solid fats and added sugars. The foods that are calorie-dense lead to obesity and will increase the risk of cancer. Only moderate amounts of animal proteins may be consumed. Eating too much quantity of processed meats such as hot dogs, bacon and ham will increase the risk of colon cancer. Alcoholic drinks will increase the risk of cancer of mouth, larynx, pharynx, esophagus, liver, breast, colon and rectum. People who consume more quantities of beer will have increased risk of rectal cancer. Studies had revealed that those who consume large amounts of salt, smoked, cured and nitrite-preserved food items are more prone to stomach and esophageal cancer. Too much consumption of grilled, deep-fried, barbequed or baked meat will lead to production of carcinogenic byproducts such as heterocyclic amines inside the body. Preserve foods such as jams, pickles, salted mustard green and century eggs may be avoided since they contain carcinogenic nitrites. Excessive intake of vitamin supplements is not good for cancer patients since they may act as antioxidants and interfere with chemotherapy.
Those who adhere to a regular schedule of physical exercises will be able to reduce their weight significantly and thereby reduce the risk of cancer.
Conclusion
While the diet that consists of fruits, vegetables, whole grains, spices, healthy fats and lean protein will prevent cancer the diet that consists of processed meat, salt, alcohol and refined carbs will increase the risk of cancer. A diet which is rich in fruits, vegetables and whole grains is not a remedy for cancer but, it can significantly lower the risk of cancer.