The role of nutritional factors in prevention of cancer: A systematic review

The role of nutritional factors in prevention of cancer: A systematic review
Shekufe Zarei,^1,* Abbas Sattari,²
1. Department of Nursing, Faculty of Nursing, Bandar Abbas Branch, Islamic Azad University, Bandar Abbas, Iran.
2. Nurse, Persian Gulf Hospital affiliated with Social Security, Bandar Abbas, Iran
Introduction: Introduction: With the increasing prevalence of cancer in worldwide and changes in cancer patterns, the role of preventive agents of this disease has been considered. Nutritional patterns play an important role in preventing cancer. Therefore, the present study was conducted with the aim of a systematic review of the role of nutritional factors in prevention of cancer.
Methods: Methods: The present study was conducted by systematic review. To access the content related to nutritional factors and cancer prevention, articles indexed in databases, Proquest, Science Direct, Pubmed, Scopus, Googlescholar, SID were used. Keywords including nutrition, cancer, diet and prevention were searched over 2000 to 2020. According to the defined criteria, finally 25 articles were reviewed in this study.
Results: Results:The role of nutritional factors in cancer prevention in each type of cancer was investigated. The results showed that very hot drinks and foods and alcohol intake increase the risk of cancers oral cavity, pharynx and esophagus. Also,fruits and vegetables reduce the risk of these cancers. Grilled meat, salted fish and alcohol intake increase the risk of stomach cancer and fresh fruits and vegetables, green tea, garlic, saffron, omega-3 such as fish, tomatoe, Black raspberries, walnuts, hazelnuts, red grapes, black tea, onions, berries reduce the risk of stomach cancer. In colorectal cancer, increase the consumption of fiber and reduce the consumption of processed meats, vitamins A, C and beta-carotene, calcium, whole grains reduce the risk and red meat more than 4 times a week, fried foods, high-fat diet, grilled foods, Smoked fish, salty meat and pickles increase the risk. Aflatoxin and alcohol intake are related diet factors for liver cancer. Also, coffee reduces the risk of liver cancer. Some studies show that the risk of pancreatic cancer increases with high consumption of meat and decreases with vegetables. Although smoking is a major cause of lung cancer, studies have shown that low intake of vitamin A, fruits, vegetables and beta-carotene are involved in lung cancer. The only risk factor for breast cancer is alcohol. Fruits, vegetables and nutrients such as carotenoids and folate reduce the risk of cervical cancer. In total, fat, alcohol, salt, foods containing nitrate and nitrite, high-caloy foods high risk of cancer and high fiber, fresh vegetables, carotenoids such as tomatoes, vitamins C, E and selenium, legumes, carrots, broccoli , Sweet potatoes, pumpkin oil and pumpkin seeds reduce the risk of cancer.
Conclusion: Conclusions: Evidence for the crucial role of nutrition in cancer suggests that approximately 35% of cancer deaths are reduced with proper diet. Therefore, it is necessary to take measures to correct dietary patterns in order to prevent cancer. The Cancer Prevention Association has made recommendations to improve diet and prevent cancer, including diversifying meals, emphasizing the consumption of whole grains, breads and cereals, fruits and vegetables, eating low-calorie foods, and limiting salt intake and Alcohol. Therefore, health policy makers should design and implement careful planning in this regard to change dietary patterns in families.
Keywords: Nutrition, Cancer, Diet, Prevention