Introduce some of the in-text references with introductory phrases.  

This section provides a review of different sources relating to the topic of study with the aim of determining the gaps that have not been researched on by other scholars. In determining the relevance of the sources to the prevention of cancer, the relationship between nutrition and cancer either in causal perspectives and in protective perspectives will be assessed. Through a thorough analysis of the sources, a research gap will be determined through which this study aims at focusing on.

There is a high correlation between nutrition practices and colorectal cancer where nutrition plays a big part in both the protective role and in causal role. There are various nutrients that are associated with causing colon cancer which includes fat from red and processed meats. In preventing the development of the cancer, dietary rich in fruits and vegetables are recommended (Thanikachalam, 2019).

Nutrition practices have a great role in the development of breast cancer where dietary patterns featured with high intake of unrefined vegetables, cereals, nuts improve survival after diagnosis of breast cancer. Also, low consumption of red meat and saturated fatty acids increases chances of survival after diagnosis of the cancer (De, 2019).

Selenium can be used in preventing the development of cancer in the first place but when supplemented with other nutrients such as Vitamin E. Selenium is a mineral which plays an important role in the protection of the body against damages resulted from oxidative stress. It is also important in metabolism and thyroid function. Selenium is found in foods such as seafoods, Brazil nuts and organ meats in large quantities or other foods such as cereals and muscle meats though in smaller quantities (Vinceti, 2018).

Based in an assessment conducted by the use of the Scored-Generated Subjective Global Assessment (PG-SGA), nutritional practice of an individual has a direct relationship to their risk of developing a given type of cancer. Diets which cause nutritional conditions such as obesity increases the risk of the obese individuals in developing many types of cancer (Jager-Wittenaar, 2017).

Nutritional practices such as the use of the traditional Mediterranean diet is linked with improvement of life quality and longevity through reduction of the risk of most common pathologies such as cancer (Battino, 2019).

Based on the literature review of the existing research work on the relationship between nutrition and the development of cancer, it is evident that there is a need to establish the role of a complete balanced diet on the development of cancer. The study will determine the link between the two variables in the process of supporting ways in which cancer can be prevented through a nutrition practice of using a balanced diet.

Reference

Battino, M., Forbes-Hernández, T. Y., Gasparrini, M., Afrin, S., Cianciosi, D., Zhang, J., … & Giampieri, F. (2019). Relevance of functional foods in the Mediterranean diet: The role of olive oil, berries and honey in the prevention of cancer and cardiovascular diseases. Critical reviews in food science and nutrition, 59(6), 893-920.

De Cicco, P., Catani, M. V., Gasperi, V., Sibilano, M., Quaglietta, M., & Savini, I. (2019). Nutrition and breast cancer: a literature review on prevention, treatment and recurrence. Nutrients, 11(7), 1514.

Jager-Wittenaar, H., & Ottery, F. D. (2017). Assessing nutritional status in cancer: role of the Patient-Generated Subjective Global Assessment. Current opinion in clinical nutrition and metabolic care, 20(5), 322-329.

Thanikachalam, K., & Khan, G. (2019). Colorectal cancer and nutrition. Nutrients, 11(1), 164.

Vinceti, M., Filippini, T., Del Giovane, C., Dennert, G., Zwahlen, M., Brinkman, M., … & Crespi, C. M. (2018). Selenium for preventing cancer. Cochrane database of systematic reviews, (1).