The Effect of Special Diet on Progress of Colon Cancer

Introduction

Overview

This part covers the study background, research questions, academic and practical relevance, previous studies, methodology, sources of data and information, and limitation of the study.

Study background

Currently, cancer is the cause of nearly 12 percent of deaths across the globe translating to over 9 million people per annum. The number is anticipated to increase to over 12 million people in 2030 (Nooyi and Al-Lawati 1736). As stated by Ferlay and Bray, “the colon cancer is the third most predominant malignancy in men and positions second in ladies” (2893). The prevalence rate is higher in the advanced economies compared to developing economies. Be that as it may, the pattern is changing. Despite the fact that the trend and frequency for colorectal cancer from the advanced nations have been accounted for in most studies, there is a shortage of such information from the Arab world, and up to the present time, very few studies have been conducted in Oman (Kumar, Burney, Furrukh and Al-Moundri 4855).

In Oman, colon cancer is common in men than women, and the prevalence rate in the country is showing no sign of decline. With enhanced life expectancy in Oman, the outright cost of colon cancer might become equally higher in the near future (Kumar, Burney, Furrukh and Al-Moundri 4853). It is the fourth most predominant cancer among the Omani residents. With respect to gender, it is the second most predominant cancer among men and fourth most ubiquitous among women (Kumar, Burney, Furrukh and Al-Moundri 4854).

At the moment, the current data show that Oman has a higher incidence of colon cancer in the Gulf region despite the fact that they have the same culture and way of life. The data on colon cancer incidence in the GCC countries is readily available due to the introduction of compulsory cancer diagnoses notification. Nevertheless, the mortality figures attributed to colon cancer may not be accurate because the figures are mainly based on individuals who have passed away in the infirmary. Because many individuals pass on at home, mortality figures based on hospital figures inescapably underestimate the actual mortality (Kumar, Burney, Furrukh and Al-Moundri 4856).

Numerous studies have linked dietary and nutritional factors to the etiology of colorectal cancer. In addition, many theories have been suggested to explain the effect of different dietary components on the development and progress of colon cancer. In actual fact, diet is one of the leading risk factors for colorectal cancer. However, few studies have been conducted to determine the correlation between diet and colon cancer on its own. As a result, the effect of diet on the progress of colon cancer is unclear (Lofano, Principi, Scavo and Di Leo 7).

The larger parts of risk factors for colon cancer are adaptable, and incorporate the consumption of food rich in saturated fats and obesity. Disproportionate consumption of red meat (boiled, grilled or barbequed) is an additionally known risk element. As an aftereffect of these lifestyle elements, there is a considerable difference in frequency and death rate from colorectal cancer all over the globe (Ferlay and Bray 2894). According to Winkels et al., “there is a well-known disparity between rectal and colon cancer with regard to lump growth and development, reappearance, and endurance, but few studies have been conducted to establish the impact of dietary risk factors on colon cancer” (1473).

Winkels et al. assert that excessive ingestion of red and processed meat and alcoholic drinks, as well as low ingestion of diets comprising of dietetic fiber compellingly, enhances the risk of colon and rectal cancer (1473). They link colorectal cancer incidence and mortality to excessive body fat and obesity. Women with a body mass index (BMI) exceeding 29, compared with a body mass index of below 21, have an attuned risk reduction for colorectal cancer incidence of 1.45 at 95% confidence interval). In addition, a BMI of 30 to 35 for both gender have an attuned risk reduction for colorectal cancer mortality, compared with individuals with a body mass index of 18 to 25 of 1.47 at 95% confidence interval (Winkels, Heine-Broring, van Zutphen, van Harten-Gerritsen, Kok, van Dujnhoven and Kampman 1474).

This thesis will emphasize on the relationship between different dietary and nutritional components on the development and progression of colon cancer, with special focus on Oman people. Oman has experienced numerous changes in lifestyle and eating habits over the last decades. Many studies attribute the increase in colon cancer incidence and mortality in the country to these changes. The incidence of colorectal cancer in Oman is also linked to increased consumption of red meat, fast food, and obesity. For this reason, the thesis provides a broad overview of the relationship between these dietary components and colon cancer and the development of these relationships over time.

Research questions

There are three fundamental questions that are to be answered in this study. The first question is how various dietary and nutritional components affect the development and progression of colon cancer. This question will be answered with the help of the following sub-questions:

  1. How is the cancer incidence in Oman with a specific focus on colorectal cancer?
  2. How is the incidence of colon cancer varying from one geographical location to another in Oman?
  3. What is the pattern of food consumption in Oman:
  4. What is the connection between dietary patterns and risk of colon cancer in Oman?
  5. What is the effect of excessive intake of red meat and low intake of staple plant foods on the development and progression of colon cancer in Oman?
  6. How is obesity linked to the risk of colon cancer?

The second question is what steps should be taken by the government and other stakeholders to avert the high incidence of colon cancer in Oman. To answer the above research questions, the thesis is organized as follows: chapter II explores the cancer incidence in Oman with a specific focus on colorectal cancer. The chapter will also look at the pattern of food consumption in Oman. Last but not least, the chapter will examine the relationship between the dietary patterns and risk of colon cancer. Chapter III will deal with the impact of excessive intake of red meat on the development and progression of colon cancer in Oman. In addition, the chapter explores the link between obesity and colon cancer. Chapter IV is the most significant chapter of this thesis: it explores different measures that should be undertaken by the government and other stakeholders to minimize the incidence of colon cancer in Oman. Finally, Chapter V presents conclusion and recommendation.

Academic and practical relevance

This thesis presents an analytical synopsis of the relationship between various dietary and nutritional components and the development and progression of colon cancer with a specific focus on Oman. This paper presents information that will be useful for researchers, academicians, students and other individuals interested in the topic under study. Numerous essays and reports have been carried out on the subject, especially in the developed economies. However, there are very limited studies that have been conducted in the Arab world, and up to the present time, very few studies, if any, have been conducted in Oman. Therefore, the thesis will be among the pioneer studies that have been carried out to establish the link between various dietary and nutrition components and colon cancer in Oman. In addition, it will add to the growing body of literature related to the incidence of colorectal cancer in the Arab world. Last but not least, the findings of this study will be beneficial to policy makers to come up with strategies and plans to help in combating the spread of colon cancer in the country.

Previous research

  1. Cancer Incidence in Oman 2012. This is a report prepared by Al-Siyabi, Al-Lawati, A-Gharbi and Al-Wahaibi in 2012. The paper was submitted to the department of Non-Communicable Diseases and Directorate General of Primary Health Care in the Ministry of Health. The report explored incident rates and diagnosis of common cancers in the Sultanate of Oman from 1996 to 2012. The data used in the analysis was acquired from the National Cancer Registry and the Directorate General of Civil Status. The study established a high incidence of cancer in Muscat (8.7 per 100000) and Dhofar (7.9), while the lowest incidence rate was recorded at Al Wusta (0.0 100000). The high incidence rate in Muscat is due to the fact that many cancer cases are referred to the Royal hospital in the capital.
  2. Cancer Incidence in Oman. This is also a discussion paper written by Nabil Al-Siyabi. The paper was submitted to the Department of Non-Communicable Disease Surveillance and Control. It explored the country’s cancer statistics and proposed various measures to combat different types of cancer in the country, including colorectal cancer. The paper emphasized on the ideal use of the available resources with increased corporation and coordination between the state and different stakeholders to prevent the spread of colon cancer.
    The highest incidence rate was recorded in Muscat (8.7 per 100000) and Dhofar (7.9), while the lowest incidence rate was recorded at Al Wusta (0.0 100000).

Methodology

This includes is the output of a progression of choices of the researcher in regards to how the study will be directed. The research methodology is nearly connected with the system of the study and aides making arrangements for executing the study. The study will use a qualitative technique to carry out the research on the relationship between various dietary and nutritional components and colon cancer in Oman. Qualitative research is usually utilized in the social sciences, but also in other fields. Qualitative research is largely acknowledged as the best technique for assessing policies and programs because it provides clarifications to the various issues arising in a unique way that is dissimilar to other approaches.

The study will adopt a contextual analysis. The contextual analysis incorporates a point by point investigation of a subject, as well as its associated elements. Contextual analysis comes with an amazing recap of renowned works. Just about anyone with training can put forth a defense for having done a pertinent study at some point or another in their life. Relevant studies can be conveyed by following a proper research strategy. In carrying out a contextual examination, the subject being focused on might be an individual, association, event, or exercise, existing at a specific point. For example, therapeutic science has presented both known contextual studies of individuals and relevant investigations of medicinal practices.

The study depended on desk research, which is an array of existing data accessible in the secondary sources, that is, government portal, private information and web database (Outhwaite and Turner 22). The auxiliary information was gathered from books, journals, pertinent articles, and the web. While gathering optional information, especially from online sources, the accompanying techniques were utilized: initially, online inquiries depended on catchphrases and equivalent words; second, titles and features were examined in order to assess the helpfulness and significance of the information gathered; third, every one of the information sources were bookmarked and characterized as per goals that had been set before the information accumulation process; fourth, the researcher applied the trump card methodology keeping in mind the end goal to minimize typing long search strings; ultimately, the prescribed links to the web page were visited at the outset.

Sources of information

Two different categories of information sources were used in this study. The first and the most important category are the primary sources. Primary sources include empirical information materials as regards the impact of different dietary components on colon cancer. These materials consist of official statements, press releases and government websites. The second categories are secondary sources. Secondary sources include books, journals and online articles published by different authors on the subject under study and the history of their relations to promote better understanding of the ties.

The study will employ a search strategy to appraise the two sources of information owing to the fact that a methodological approach minimizes the probability of missing significant materials. It also assists in locating previous studies. As a result, this thesis will pursue the following search strategy, namely: article review and listing key references and words and limitation. Article review gives a sense of what the study will include and serves as an initial point for noting down key words. On the other hand, key references help in learning more about the subject of study. References also assist in refining and identifying the keywords.

The references include articles, journals, books, and websites. The original list of keywords included: “colorectal cancer”, “colon cancer”, “incidence”, “progression”, “risk factors”, “dietary components“ , “body mass index”, “preventions”, “overweight”, “obesity”, “food pattern”, “red meat”, socioeconomic, and “staple food”. Each title was searched using the above keywords. Limits were established so as to have a clear-cut search. Since colon cancer is mainly linked to dietary components, the main focus was on red meat, dietary fiber, and processed food. Exhaustive molecular science was beyond the scope of the study. Owing to the massive volume of information on dietary components and colon cancer, the study was restricted to government and institutional reports.

Extent of the study

The extent of the study alludes to the parameters on which the study works. The study focuses on Oman due to the fact that it is leading in the Gulf region in terms of colon cancer incidence and mortality. Furthermore, the trend and frequency of colorectal cancer from the Arab world has not been properly accounted for in many studies. Lastly, the study was mainly based on qualitative approach. The qualitative approach was advantageous because of constrained time and resources.

Cancer Incidence and Risk Factors

The colorectal cancer Incidence in Oman

Regionally, colorectal cancer is the eighth most predominant cancer in the Gulf region. However, Oman and Kuwait account for the highest number of incidences and mortality (Ahmedin and Bray 70). Given the fact that Gulf member states are assumed to have the same culture and way of life, it might appear unusual that colon cancer is highest in Oman compared to the rest of GCC member states (Nooyi and Al-Lawati 1735). Cancer recording in Oman began in 1985, though infirmary-based. In 1996, a nationwide cancer registry was set up to incorporate the entire populace. In any case, it was until early 2000 that cancer notification got to be mandatory (Nooyi and Al-Lawati 1736).

The data and information regarding colorectal cancer incidence are available in the yearly cancer reports published by the National Cancer Registry. In 2012, the Country recorded an average of 116 cases per annum for both men and women. The yearly age-standardized incidence rate was 10.2 and 8.5 (95 percent confidence interval) per 100000 for men and women, in that order. The incidence rate varied between the key geographical areas in the country. The highest incidence rate was recorded in Muscat (8.7 per 100000) and Dhofar (7.9), while the lowest incidence rate was recorded at Al Wusta (0.0 100000). The high incidence rate in Muscat is due to the fact that many cancer cases are referred to the Royal hospital in the capital.

Population distribution in the country by regions in 2012. Source: (Al-Siyabi, Al-Lawati, A-Gharbi and Al-Wahaibi 10)
Figure 1: Population distribution in the country by regions in 2012. Source: (Al-Siyabi, Al-Lawati, A-Gharbi and Al-Wahaibi 10)
Colorectal cancer cases by regions (incidence rates per 100 people). Source: (Al-Siyabi, Al-Lawati, A-Gharbi and Al-Wahaibi 45)
Figure 2: Colorectal cancer cases by regions (incidence rates per 100 people). Source: (Al-Siyabi, Al-Lawati, A-Gharbi and Al-Wahaibi 45)

The incidences in South Al-Batinah and South Ash Sharqiya were also high. The 95 percent confidence interval for the standardized morbidity ratios for Musandam and Madha are relatively large because of less number of inhabitants (Al-Siyabi, Al-Lawati, A-Gharbi and Al-Wahaibi 45). According to Al-Siyabi, Al-Lawati, A-Gharbi and Al-Wahaibi, the population of Musandam and Al-Wusta in 2012 were 23,413 and 20,360 respectively. According to the 2012 yearly cancer report, Oman and Kuwait had the highest age-standardized incidence rate of colorectal cancer for both men and women below and above 45 years compared to other GCC countries”. Among men, all the GCC member states have a statistically lower risk of colorectal cancer than Oman at 95% confidence interval, with the exception of Kuwait (Al-Siyabi, Al-Lawati, A-Gharbi and Al-Wahaibi 44).

Age-standardized incidence rates of colon cancer in Oman and other GCC countries. Source: (Al-Siyabi, Al-Lawati, A-Gharbi and Al-Wahaibi 44)
Figure 2: Age-standardized incidence rates of colon cancer in Oman and other GCC countries. Source: (Al-Siyabi, Al-Lawati, A-Gharbi and Al-Wahaibi 44)

The pattern of food consumption in Oman

A survey conducted by the Ministry of Health in collaboration with the Institute of Research for Development found that the vast majority of Omani citizens consume grain and grain products. In fact, it is their key source of energy. Fruits and vegetables are consumed in adequate amounts. However, the consumption of fruits and vegetables is comparatively low among children and teenagers. Red meat is highly preferred over fish for protein. Additionally, fats are habitually consumed, but in limited quantities (Moursi 8).

Normally, nearly all the age groups have at least three meals a day in Oman. Morning and afternoon snacks are becoming a habit among the urban residents. As stated above, grain and grain products constitute the bulk of the Omani citizens’ diet. The most common grain and grains products include rice, bread, and pasta. The amount of grain and grain products consumed are highest among male adults, followed closely by teenagers and then adult females, and lastly children (Moursi 8). This does not come as a surprise because many recipes in Oman are hinged on grain and grain products, for instance, Biryani, Orsea, and Harees. Most of the grain and grain products are consumed in refined form. The country’s staple foods are rice and bread. The breads are often eaten in an assortment of ways and are served in almost all the meals, whereas rice is commonly served at lunch hours. The different sorts of bread include roqal, roqaq, boori, brata and tannoor (Moursi 9).

The dietary components rich in high-quality proteins and accessible micronutrients are common among all the age groups, particularly animal-source foodstuffs. Red meat is more often consumed than fish (73% versus 45% in that order), which means that 50g of meat is consumed per individual every day as compared to 27g of fish. Milk, was for the most part, less much of the time consumed than other dairy products, for instance, ghee and butter. However, the level of milk consumption is high among the young children (Moursi 10).

The primary sorts of fats consumed by the Omani populace are vegetable oil and ghee added to food in the food preparation process. Despite the fact that fats are normally consumed among all the age groups, the amount consumed is comparatively low on a daily basis. The adults consume more fats (10-11g) compared to children and adolescents (5g) (Moursi 10). The consumption of fruit and vegetables is high among the adults (843-85%) and comparatively low among the teenagers and children (60-65%). However, the consumption of fruits and vegetables rich in vitamin C (oranges and fresh lemons) is high and consistent among all the age groups. Fruits and vegetables rich in vitamin A (mangoes, papayas, and carrot) are uncommon among all the age groups (Moursi 11).

The daily intake of refined grains and grain products in Oman exceeds the WHO cut-point. On the other hand, daily consumption of fruits and vegetables fall below the acceptable standards, except for fruits rich is potassium. The daily consumption of red meat for children and youngsters are close to the acceptable standards, whereas the daily consumption of red meat for adults exceedingly surpasses the acceptable standards. Besides, milk consumption among the children is exceedingly high and low among the adolescents and adults. Last but not least, the consumption of legumes and pulses are way much below the recommended amounts, as well as fats (World Health Organization 5).

A report released by the Department of Nutrition in 2009 noted that change in lifestyle as a result of urbanization and globalization has led to significant alterations in the Omani diet (Department of Nutrition 13). High fat and processed foodstuff are increasingly becoming common among the Omani population with children and adolescents being the greatest victims of the unhealthy feeding habits. The vast majority of the urban residents, especially the working-class have a high affinity for snacks and junk foods. This has led to an increase in the pervasiveness of chronic ailments and obesity; a trend that is also replicated in the neighboring nations (Department of Nutrition 14).

Moreover, the nutritional trend in Oman has changed from a normal intake of nutrient rich foodstuff, for instance, vegetables and fresh fruits to increased intake of inundated greasy foods, processed energy giving foods and fast foods. The unhealthy eating habits and deskbound way of life are the main causes of corpulence which is highly attributed to non-communicable ailments among the grown-ups in Oman. Unless essential precautionary measures to fight corpulence are introduced, non-communicable sicknesses will keep on draining the healthcare system (Department of Nutrition 14). Last but not least, westernization in the MENA nations has led to countless western impacts, mainly in the greater accessibility of diets that are rich in fats, sugar, and starches. Therefore, westernization has also played a key role on the escalation of obesity. On the other hand, individuals living in segregated provincial ranges still keep up a Bedouin way of life and eat customary nourishments and subsequently have lower corpulence rates than those in urbanized areas (Rabay and Salameh 650).

The relationship between the dietary patterns and risk of colon cancer

Dietary components are believed to contribute approximated 30 percent of cancer in Europe and America, making it the second avoidable cause of cancer after tobacco. Nonetheless, the contribution of dietary factors to cancer in the least developed economies and developing economies is thought to be about 20 percent. For this reason, unearthing the impact of dietary factors on cancer is of great significance to the public health. However, current studies have not adequately unraveled the actual effects of dietary factors on cancer, leaving exasperatingly enormous areas of a doubt (National Institutes of Health 2).

Vast numbers of the unmistakable speculations on the impact of eating regimen on cancer risks have been developed from the study of the relationship between eating trends and cancer rates in many jurisdictions across the globe. In the 1970s, it was noted that advanced economies had food rich in animal proteins, fats, and sugar. Besides, these countries recorded the highest cases of colorectal, breast and prostate cancer (National Institutes of Health 2). On the contrary, least developed economies and developing economies characteristically have diets that are full of starch, low animal proteins, low fats and low sugar. These countries are also associated with low rates of colorectal, breast and prostate cancer, and high rates of the esophagus, stomach and liver cancer. Nonetheless, cancer rates in the least developed and developing countries are changing with time. This is attributed to globalizations and adoption of western culture, for instance, the formerly low levels of colorectal cancer in Japan has increased due to the Westernization of the Japanese diets (National Institutes of Health 3).

A broad catalogue of food that could enhance or lessen the dangers of colorectal malignancy has been suggested in many kinds of researches. Some of these foods have been investigated exhaustively, while others have been tried in one or two studies. A report published by the World Cancer Research Fund titled “Food, Sustenance, Physical Exercises and the Deterrence of Malignancy” reviewed all the available studies on the impact of various diets on the growth and development of cancer in the body (World Cancer Research Fund 70). The review acknowledged the different etiological factors linked to colorectal cancer. Nonetheless, the findings were not arranged in accordance with the subsite, hence the findings are less conclusive.

Table 1 below was adapted from a study conducted by Lima and Gomes-da-Silva. Whereas there is no substantial proof regarding any sort of diet being a risk factor for colorectal cancer, the report postulates that fruits and non-starchy vegetables are plausible shields against colorectal cancer (Lima and Gomes-da-Silva 237). Vegetables such as Broccoli, cauliflower, Brussels and sprouts contain folic acids which protects against DNA damage that are linked to cancerous growth in the colorectal pathways. On the other hand, citrus fruits contain carotenoids that are probable anti-tumorigenic except for its antioxidative characteristics (Lima and Gomes-da-Silva 238).

Dietary components which may minimize the risk of colorectal cancer. Source: (Lima and Gomes-da-Silva 238)
Table 1: Dietary components which may minimize the risk of colorectal cancer. Source: (Lima and Gomes-da-Silva 238)
Dietary components which may minimize the risk of colorectal cancer. Source: (Lima and Gomes-da-Silva 238)
Table 1: Dietary components which may minimize the risk of colorectal cancer. Source: (Lima and Gomes-da-Silva 238)

Dietary fiber and colorectal cancer

Lofano et al. also emphasize on the role of diet in the etiology of different categories of cancer (1). They explain that colorectal cancer is, by and large, high in populations with excess consumption of meat and low consumption of food rich in dietary fibers (principal plant foods). Food rich in dietary fiber enhances fecal mass and, therefore, speeds up the peristalsis process and minimizes the period of exposure to carcinogenic elements. Throughout the years, a number of theories have been proposed to explain the anticarcinogenic nature of dietary fibers. These theories assert that the fibers are essential in the dilution of colorectal carcinogens, the obstruction of cell growth and proto-oncogenes expression, and the facilitation of colonocytes separation (The International Agency for Research on Cancer 102).

Be that as it may, the defensive role of the utilization of these nourishments against cancer is still questionable. Indeed, a report released by the World Cancer Research Fund (WCRF) in 2007 stated that there is no conclusive evidence to confirm that staple plant foods (fruits and vegetables) safeguards against colorectal cancer. The report downgraded the previous reports released by the same organization describing the relationship between dietary fiber and colorectal cancer as probable. However, the organization was in the forefront in advocating for adequate consumption of fruits and vegetables to reduce risks of various types of cancer. It recommended no less than five bits of fruits and vegetables every day, corresponding to about 400g per day (World Cancer Research Fund 75).

By and large, the scientific data do not demonstrate a reasonable relationship between dietary fiber (fruits and vegetables) and the danger for colorectal malignancy, in spite of the fact that they are attuned with a petite decrease in the risk (World Cancer Research Fund 75). One of the recent studies highlighted the relationship between dietary factors and colorectal cancer. According to the study, dietary factors and recommended body weight can reduce the risk of colorectal cancer by 30 percent. The study was based on body mass index, aggregate caloric consumption across different age groups and gender. However, the findings of other prospective studies have been unclear (Burkitt 965; Beliveau and Gingras1908), and extensive studies have postulated that increased consumption of dietary fiber has at least considerable effect on reduction of colorectal cancer (Aykan 289).

Dietary fibers also play a huge part in cell reinforcements and other conceivably bioactive phytochemicals such as flavonoids. The cell reinforcement agents (antioxidants) hold unrestricted radicals and receptive oxygen particles, safeguarding against the negative effects of oxidation. What’s more, some antioxidants straightforwardly repress the expression of cytochrome enzymes, which assist in breaking down toxic substances that are linked to the growth and development of various cancer cells (Aykan 290).

High-fat diet and colorectal cancer

Some studies link high intake of food containing high amount of fats and oils to increased risk of colorectal cancer (Calle and Thun 78), but the actual relationship is yet to be confirmed (Lofano, Principi, Scavo and Di Leo 2). However, there is a high probability that general consumption of fatty acids may contribute to the development and progression of colorectal cancer. For instance, a number of studies have established an inverse relationship between n-3 polyunsaturated fatty acids and colorectal cancer (World Cancer Research Fund 33), despite the fact that the outcomes are definitely not totally persuading. A small number of studies have reviewed the association between colorectal tumors and trans-fatty acid intake. However, the results are very inconsistent (World Cancer Research Fund 36).

Calle and Thun argue that unsaturated fats are the molecules upon which enzymes act for eicosanoid creation and eicosanoids can cause proinflammatory passageways that encourage colorectal carcinogenesis (6365). Prostaglandin E2 (PGE2), originating from arachidonic acid assumes a critical role in the development of cellular populaces in the colorectal chamber and consequent development of adenoma. Cyclooxygenase inhibitors, on the other hand, prevent propagation, prompt apoptosis and restrain angiogenesis in the colorectal pathways. Inhibition of both cyclooxygenase 1 and cyclooxygenase 2 tend to be efficient in preventing polyp development and extraordinarily lessens the risk of colorectal cancer. It gives the idea that decreasing the level of prostaglandin E2 in ordinary tissue could minimize the risk of polyp development; furthermore, prostaglandin E2 has been recognized as a suitable prevention terminal point (Calle and Thun 6366).

Protein and colorectal cancer

An all-inclusive appraisal by the World Cancer Research Fund and the American Institute for Cancer Research concluded that the proof that red meat and processed animal protein are among the etiological causes of colorectal cancer is undoubted. Therefore, they recommend low consumption of red meat and processed protein. Nonetheless, they acknowledge that this would negatively affect the meat processing industry. The study showed that 120g per day increase in red and processed meat enhances the risk of colorectal cancer by nearly 30 percent (World Cancer Research Fund and American Institute for Cancer Research 44).

In the analysis, the average relative risk linked to the intake of red meat is modest. However, it is noteworthy in a three-pronged analysis (comparative risk=1.16, 1.36, and 1.27 in that order), as is the risk linked to the intake of processed meat (comparative risk=1.48, 1.33, and 1.21, correspondingly). The three-pronged analysis approximates that one gram of processed meat enhances the risk of colorectal malignancy eleven times, six times and two times more than unprocessed meat in that order (World Cancer Research Fund and American Institute for Cancer Research 44). A number of theories have been used to clarify the link between red meat consumption and risk of colorectal malignancy. Red meat improves the development of well-known cancer-causing N-nitroso compound in the human waste. Over-heated meat contain a sweet-smelling chemical agent (aromatic amine) that initiate the growth of tumors in the colon, mammary glands and prostate as it has been witnessed in rats and apes (World Cancer Research Fund 16).

Be that as it may, the chemical agent plays a significant role in the development and progression of colorectal cancer. In addition, the dosage of aromatic amines that induces malignant growth in animals is a thousand times greater than the dosage presents in human food (World Cancer Research Fund 17). Red meat also has heme, an iron-rich constituent of the red-blood cell. Dietary heme enhances the proliferation of colonic epithelial and increases the toxicity of fecal water in rodents. Empirical studies have shown that dietary heme stimulates the development of preneoplastic lacerations in the colorectal pathways. Besides, dietary heme enhances the volume of phospholipid hydroperoxides in fecal water and toxicity of the same (World Cancer Research Fund 18).

Carbohydrates and colorectal cancer

Many studies posit that reduced consumption of carbohydrates minimizes the risk of colorectal cancer by inhibiting the development of colonic polyp. The intricate long-chain carbohydrates are regarded as extremely defensive as compared to refined saccharose (FAO/WHO 9). Scientists have affirmed that constant hyperglycaemia and the ensuing insulin discharge are impetuses for increased proliferation of colorectal epithelium and elements associated with the progression of colorectal cancer. However, this relationship has not been established in other studies. The intricate long-chain carbohydrate is supposed to convey nearly three-quarter of the entire energy, whereas processed saccharose is supposed to convey not more than 10 percent of the energy. For this reason, excessive consumption of saccharose and processed sugar are risk factors for colorectal cancers, whereas multifaceted long-chain carbohydrates found in starchy food have a shielding effect (FAO/WHO 11).

Vitamins and colorectal cancer

There is an expanding proof that that calcium and vitamins, especially vitamin D play a critical part in minimizing the risk of colorectal cancer. The two are biologically bound and have a protective effect. Studies using cell cultures and animal models have shown that calcium and vitamin D act by promoting apoptosis. The proapoptotic activities of vitamin D are associated with the risk of colorectal cancer. Patients with tumors in the epithelial tissues have three times higher odds at 95 percent confidence interval (Aykan 293). On the other hand, there has been a conflicting report regarding folic acid, which is one of the soluble vitamins. Epidemiological research indicates that folic acid is significantly linked to low risk of colorectal cancer, implying that folic acid has a protective effect. In contrast, the American cancer prevention research established that the folic acid supplementation group had a high risk of having colorectal cancer. Therefore, the role of folic acid may be double-pronged, that is, it prevents the development of colorectal cancer in the early stage and promotes progression of cancer in the later stage (Aykan 294).

The Continuous Update Project (CUP) being undertaken by the World Cancer Research Fund in collaboration with American Institute for Cancer Research established an inverse relationship between dietary folate and colon cancer (7). On the other hand, the study established a direct relationship between dietary folate and rectal cancer. To be precise 100mcg/d of dietary folate reduces the risk of colon cancer by 16 percent, but the study did not reach statistical significance.

Risk factors for colorectal cancer in Oman

The information regarding the etiological factors of any form of ailment is very crucial, particularly for policy makers to initiating corrective measures. However, there are cases where the etiological factors are problematic to find. This poses a huge challenge to the policy makers as regards the measures to be undertaken or the most appropriate measure. Due to numerous biases, many environmental studies are hinged on hypothesis building as opposed to finding a causal relation. The most common bias is ecological fallacy which is associated with the disparity in individual and group observation (Al-Riyami and Afifi 601).

As already been established, the rate of colorectal cancer incidence in Oman is higher than the neighboring GCC member states. This begs the question on what is causing this huge disparity. The speedy financial improvement and changing lifestyle in the Sultanate of Oman in the last two decades have played a huge part in the epidemiological transition. The healthcare sector which was troubled with communicable maladies in the past is presently overburdened with non-communicable diseases such as cancer. The associated risks factors are almost the same as in most advanced economies. Nevertheless, numerous studies have established that high incidence of colorectal cancer in Oman are linked to weight gain, changing eating habits and lifestyle, socioeconomic factors and low consumption of dietary fiber (Department of Nutrition 31; Al-Riyami and Afifi 602).

Weight gain and obesity

Just like in the Western countries, the problem of weight gain in Oman has gotten to an epic level. A national cross-sectional study carried out in early 2012 established a significant increase in weight gain among Omani men and a reverse trend among women. The increase in weight gain was almost the same as in the United States. Both overweight and obesity are partially attributed to speedy urbanization. Owing to the increased petroleum revenue and rapid urbanization, a growing number of Omani men have been streaming to the capital in search of white-collar jobs. In addition, increased levels of education, the overall decrease in fertility rates and greater consciousness of self-image among the Omani women are associated with the general decrease in weight and obesity among women (Al-Riyami and Afifi 602).

Rapid urbanization and improved literacy level have brought about the change in lifestyle, including dietary changes, sedentariness, and increased levels of cigarette smoking (Al-Riyami and Afifi 601). The consumption of high-fat calorie-dense food, processed sugar and salt are on the rise, while people have become lazier. Owing to increased standards of living and advancements in technology, people have become more inactive (Al-Riyami and Afifi 602). Many families own a car, which means few people are walking to work. Besides, the office jobs in the public sector are preserved for the citizens, while physical jobs are often carried out by expatriate (Al-Riyami and Afifi 603).

The increased number of overweight females is associated with the sociocultural restrictions imposed on women. Apart from the capital Muscat, the requirement for male and female separateness applies. Even though the number of overweight males has increased and the number of overweight females decreased, obesity is still widespread among females. As a result, most women cannot access gym facilities and the available women-gyms are very few and costly, making it next to impossible for women to exercise (Al-Riyami and Afifi 603). In addition to improved standard of living and advanced technology, cultural norms have also played a significant part in promoting physical inactivity. For instance, women are not allowed to walk or exercise alone without being accompanied by a member of the family. In addition, many women play the role of a ceremonial housewife. Most of the domestic the daily routines are carried out by expatriate housemaids (Lyons and Langille 10).

Based on the World Health Organization’s cut-point, nearly 80 percent of individuals aged 20 and above in Oman are either overweight or obese compared to 70 percent in Kuwait, 30 percent in Saudi Arabia and 20 percent in the United Arab Emirates. Kuwait (35%) and Saudi Arabia (23%) have higher prevalence rates of obesity than Oman. In comparison less than 5 percent of individuals in Africa are obese (Musaiger 228). Based on the same WHO threshold, the highest numbers of individuals who are overweight and obese are from the southern region, while the southern region has the least number. This is because the southerners’ diets are rich in saturated fat compared to the rest of the country. Moreover, morbid overweight is considered as a symbol of healthiness and affluence in the southern region and, therefore, obesity is cherished and sought after (Musaiger 229).

The prevalence rate of overweight and obesity is relatively high in the urban areas than in the countryside. The rural lifestyle is still linked to physical activities, healthy eating habits and food scarcity (Musaiger 229). On the other hand, the urban areas are associated with physical inactivity due to improved standards of living and changing lifestyle. The problem of adiposity in the Sultanate of Oman has increased the burden of weight-related ailments such as diabetes and cancer. Experts warn that if the trend is not reversed, the country should be ready for a greater burden of non-communicable diseases (Guffey 88).

Changing eating habit and lifestyle

Changing eating habits and way of life are regarded as the main factors linked to food-related maladies in the GCC regions. Studies show that dietary quality, especially in the urban areas has significantly declined in Oman. The consumption of fruits and vegetables has gone down, while the consumption of junk foods and soft drinks has substantially increased. The changing dietary habits have to a large extent affected the adolescents and the youths (Lumeng, Bodzin and Saltiel 176).

Most of the urban adolescents, especially women have the habit of skipping breakfast, low consumption of fruits and vegetables, and increased consumption of soft drinks, confections and fast foods. Ladies skip breakfast as a technique of dieting or keeping their body in shape. In contrast, men skip breakfast due to time constraints or accessibility of food (Majno and Joris 27). Besides, the noteworthy epidemiological changes that have taken place in the last decades have led to a further deskbound lifestyle, hence a significant decrease in the level of bodily activities, an upsurge in the consumption of fast food, and the escalation of stress-related activities (Majno and Joris 28).

A study on the contemporary dietary patterns in Oman show that most of the urban residents consume a lot of food rich in saturated fats and calories and, therefore, increases the risk of obesity and its associated ailments (Majno and Joris 28). Individuals who skip breakfast have a habit of compensating it with in-between meals, which are rich in high calories and saturated fats. Snacks and light meal intake are popular among the urban residents. The consumption of fruits and vegetables is very low. To be specific, less 25 percent of the population takes fruits and vegetables on a regular basis, but the consumption is relatively high among the elderly people (Majno and Joris 29). Fast food is turning out to be an integral part of the lifestyle of the Omani population, especially those living in the urban areas. The consumption of fast food is high among the women compared to men due to cultural limitations on movement and the increase in home delivery services. However, men consume larger portions of fast foods compared to women (Beliveau and Gingras 1906).

Fast food offer unwholesome choices particularly among youngsters and teenagers elevating their risk of obesity due to hefty portion sizes, high calories, excess fat and sugar, straightforward starches, excess salt, and high food density (Obesity Action Coalition standard. 3). An individual could without much of a stretch take in 1,500 calories from a single meal. A typical fast food menu has the following: burger containing 850 and 25 gram fat and French fries containing 350 calorie and 20 gram fat (Obesity Action Coalition standard. 3). In Oman, most fast food chain are situated in Muscat region, for instance, 14 out of 21 McDonalds are in Muscat, 3 in Sohar , 2 in Salalah , and one in Nizwa and Buraimi. The weight rates and colon malignancy rate are high in this area.

A good number of people spend too much of their time watching television or browsing the internet, instead of participating in outdoor activities and physical exercises. As a matter of fact, the TV watching and internet browsing has changed the way the majority of Omani people use their leisure time. TV watching and internet surfing are also linked to poor eating habits among the youths (Beliveau and Gingras 1906). They are associated with snacking and less consumption of proper meals. The snacks have high calories and saturated fats and, therefore, increase the risk of overweight and obesity. However, the risk of adiposity is linked to the time spent in front of the television or computer (Beliveau and Gingras 1907).

There is an increasing trend of tobacco smoking among the Omani population. The majority smoke cigarettes (81%) followed by shisha (6.3%), gouza (7.6%), and other tobacco products (4.4%). Most of the tobacco smokers are men who start smoking as early as 15 years. Only a small number of women smoke tobacco. Shisha smoking is popular among the youths, especially the partygoers or revelers. However, the incidence of tobacco smoking in Oman is comparatively lower than in other GCC countries (Al-Riyami and Afifi 602). The low number of smokers in Oman is attributed to religion and culture. The majority of the Omani people are Muslims and smoking is highly prohibited (Al-Riyami and Afifi 603).

Generally, smoking is considerably associated with different types of communicable diseases, for instance, stroke, cancer, serious respiratory problems and heart diseases. Even though tobacco smoking is commonly linked to lung tumors, it is also very injurious to the colon and rectum. Studies show that more than 10 percent of colorectal cancer deaths are caused by smoking. The risk factors related to smoking history incorporate styles of smoking, length of smoking, and quantity of tobacco consumed per day (Centers for Disease Control 15).

Low consumption of dietary fiber

As already been stated, the eating pattern in Oman has transformed from normal consumption of heavy nutritive foods, for example, staple plant foods to increased consumption of high-fat calorie-dense food, processed meat and junk foods (Department of Nutrition MoH Oman 41). According to the medical and nutrition experts, unhealthy eating habits and deskbound lifestyle are the main causes of adiposity, which is one of the major causes of non-communicable maladies in Oman. Unless essential precautionary measures to battle weight gain are presented, non-transmittable illnesses will keep on draining the country of both human and financial capital (Department of Nutrition MoH Oman 42).

Dietary fiber also recognized as roughage is well-known for combating carcinogenic elements in the body. For a considerable length of time, studies have shown the way that enhanced fiber consumption diminishes the risk of colorectal cancer (Ferguson and Harris 17). This defensive impact might be because of fiber’s propensity to add mass to your digestive framework, shortening the measure of time that waste goes through the colorectal pathways. As this waste frequently carry cancer-causing agents, it is ideal that it is emptied as fast as could reasonably be possible. For this reason, expanded fiber diminishes chances for intestinal infection (Ferguson and Harris 18).

What’s more, when microscopic organisms in the lower digestive tract break down fiber, a chemical substance known as butyrate is produced. This chemical substance helps in inhibiting the development and progression of malignant tumors in the colon and rectum (American Dietetic Association 26). In short, food rich in dietary fiber speeds up the peristalsis process and minimizes the period of exposure to carcinogenic elements. In addition, they assist in the production of butyrate, which inhibits the growth and development of colorectal cancer (Ferguson and Harris 18; American Dietetic Association 26).

The United States polyp prevention experiment on colorectal benign tumor reoccurrence assessed the impact of strict maintenance of the following diet for 200 individuals over a four-year period: low quantity of fat, high amount of fiber, and high amount of fruits and vegetables. The experiment started in 1991 and ended in 1998 with the results published in 2009. The study showed a broad range of individual differences in the level of conformity among the subjects who took part in the study. The participants who had high levels of conformity were compared with the control group. This group had a 35 percent reduced odd of benign tumor reoccurrence. The results suggest that increased adherence to low-fat diet and high-fiber food minimizes the risk of both benign and malignant tumors in the colon and rectum (American Dietetic Association 13).

Fiber has also been known to be protective against all forms of cancer, including lung, esophagus, prostate and breast cancer. The high-fiber foods have low fat content and this may explain the advantage of consuming high-fiber grains and grain products, pulses (legumes) and vegetables and fruits (American Dietetic Association 13). Elevated quantities of fiber filter the amount of estrogen that goes to the blood stream. Estrogen is a chemical compound that is very much known for causing cancer. This is achieved by binding to estrogen and expunging them from the body through the digestive tract. By itself, fiber is capable of expelling nearly all the carcinogenic elements in the body. In addition, it should be noted that fiber-rich vegetables and fruits have a high amount of cancer-repulsing antioxidants (American Dietetic Association 15).

At the present time, Omani population consumes approximately 10 grams of fiber every day. This is way below the recommended standard. Latest studies recommend that little increments in fiber, for example, adding vegetables to French fries or having a cheeseburger on an entire wheat bun, do not provide adequate cover. Then again, when people learn to supplant high-fat, animal products such as sausages, bacon, eggs, gizzards, cheese, and liver with staple plant foods, they will without difficulty boost the level of fiber to where they offer real protection to the body against carcinogenic elements (Department of Nutrition MoH Oman 46).

Dietary fibers are both solvent and insolvent. Solvent fiber breaks up in water and is found in an assortment of natural fruits, pulses, vegetables, and grains. It condenses cholesterol in the body, stimulates a feeling of completeness, and moderates the discharge of sugars from nourishment into the blood. These activities minimize the risk of contracting communicable and non-communicable maladies. Great wellsprings of dissolvable fiber are oat, cellulose, apple, citrus fruit, strawberry, dried pulses, grain, rye powder, tubers, uncooked cabbage, and dried flour paste (American Dietetic Association 17).

On the other hand, insolvent fibers do not break down in water. They are found in grain bran, soft fleshy part of fruits, and vegetable peelings and coatings. It is the kind of fiber most emphatically connected to protection from malignant tumors and enhanced waste expulsion. Great wellsprings of insoluble fiber are bran, products of whole wheat, cereals produced from wheat bran and whole wheat product, crispy vegetables, grain products, grains, dried flour paste made from whole wheat, and rye powder. It should be noted that fiber-rich foods are excellent in combating carcinogenic elements in the body compared to fiber supplements. They provide an all-inclusive range of cancer-repellant plant compounds or phytochemicals (American Dietetic Association 18).

Socioeconomic factors

Regardless of advances in knowledge regarding the risk factors prevention and enhancements in timely identification and treatment of malignant tumors, socioeconomic factors still affects cancer incidence, deaths, and survival in Oman (Merletti, Galassi and Spadea 4). As been stated earlier, the national cancer registry is, for the most part, the legitimate wellspring of information for describing incongruities in cancer burden among various groups and regions in the country. Be that as it may, these data are mainly based on infirmary records and managerial data and, therefore, do not provide adequate information regarding an individual’s socioeconomic status (Merletti, Galassi and Spadea 56).

Nonetheless, a great deal of information regarding the socioeconomic status of the Omani population can be obtained from the census report. The country’s rate of unemployment (15%) is comparatively higher than its neighboring countries, while its income per capita ($24024) is the lowest (Ferlay and Bray 2897). Merletti, Galassi and Spadea assert that disparities in cancer incidences and mortality are linked to social and economic status, existing culture, and social inequality with poverty playing a significant part. They explain that the incidences of colorectal cancer in Oman have are high in the urban areas than in the rural areas due to socioeconomic and cultural factors. Colorectal cancer tends to be more frequent among individuals in the higher socioeconomic class. Besides, food is more available and accessible in the urban areas than in the countryside. Last but not least, weight gain and obesity are considered as a symbol of healthiness and affluence in some parts of the country and, therefore, corpulence is appreciated and desired (Nooyi and Al-Lawati 1735).

Red Meat and Obesity

The effect of excessive intake of red meat on the development and progression of colon cancer in Oman

Disproportionate consumption of red meat is a well- known risk factor for many types of cancer, including colorectal cancer. Red meat is highly preferred as a source of protein in Oman than fish and pulses. Besides, studies have shown that the daily consumption of red meat in Oman exceptionally surpasses the World Health Organization’s set standard (World Health Organization 12). Many scientific studies have linked colorectal cancer to haem, a colorant originating from the hemoglobin. Hemoglobin is protein compound found in the red blood cells. In fact, hemoglobin is what makes the blood red and is responsible for transportation of oxygen and carbon dioxide in and out of the body. Therefore, red meat is “red” due to haem.

When haem is broken down in the stomach, it releases N-nitroso compounds. N-nitroso compounds have been found to be very harmful to the deoxyribonucleic acid (DNA) of cells that line the colorectal pathways (Scowcroft par.16). To entangle things a bit it appears, that when the lining of colorectal pathways is harmed, it responds by directing the current cells to divide even more quickly to create new cells. This “additional” cell division may likewise elevate the odds of development and progression of colorectal cancer, on the grounds that each time a cell divides, it risks making a duplicating mistake in its DNA (Scowcroft par.17). Dietary heme also enhances the proliferation of colonic epithelial and increases the toxicity of fecal water in rodents. Experiential studies have shown that dietary heme stimulates the development of preneoplastic lacerations in the colorectal pathways. Besides, dietary heme enhances the volume of phospholipid hydroperoxides in fecal water and toxicity of the same (Aykan 288).

The processed meat is usually well-preserved using nitrogen-based preservatives, which are more strongly associated with different types of cancer. These preservatives are regarded as mutagenic and strong cancer-causing agents. When the processed meat is cooked, heterocyclic amines are formed on the surface. Heterocyclic amines are associated with the development of colorectal cancer by causing mutation of the K-ras and APC genes. Heterocyclic amines can also be produced when the processed meat is grilled, pan-fried or barbequed for a considerable long time.

Heterocyclic amine is formed when processed meat is cooked under a high temperature. Extremely high temperature causes reaction of amino acids, creatine, and sugar to produce an assortment of heterocyclic amine (U.S. Institute of Medicine 21). Studies have also shown that meat preparation methods are highly linked to the reoccurrence of cancer. Meat cooked under extremely high temperature increases the risk of recurrence of cancer, including colon and rectal cancer by 17 percent at 95% confidence level (Scowcroft par.19).

Red meat also contains a considerable amount of saturated fatty acid. These fats stimulate the secretion of bile acids and cell loss. Empirical studies have shown that high consumption of fat and saturated fatty acid from meat increases the risk of obesity, which consequently elevates insulin resistance and, as a result, promotes the growth of malignant tumors (U.S. Institute of Medicine 23).

Red meat also contains carcinogenic Omega-6, particularly arachidonic acid, and Cyclooxygenase (U.S. Institute of Medicine 23). As already been mentioned, Prostaglandin E2 (PGE2) originates from arachidonic acid. Prostaglandin E2 is responsible for the development of cellular populaces in the colorectal chamber and consequent development of adenoma. Cyclooxygenase, on the other hand, promotes the propagation, prompt apoptosis, and angiogenesis in the colorectal pathways. The expression of both cyclooxygenase 1 and cyclooxygenase 2 tend to encourage polyp development and extraordinarily increases the risk of colorectal cancer (Calle and Thun 6366).

Red meat also has high levels of cholesterol which produce significant quantities of cholic and chenodeoxycholic acid. The two are known to create chaos in the colorectal epithelial cells by inducing membrane agitation, oxidative deoxyribonucleic acid damage, cell division stress, and mitochondrial damage. The stress in the epithelial cells may cause an inflammatory response, which is one of the factors that promote carcinogenesis (U.S. Institute of Medicine 25). So, excessive intake of cholesterol-dense red meat creates a suitable environment for colorectal carcinogenesis, hence increased the risk of colorectal cancer. Last but not least, red meat contains sialic acids. Exposures to sialic acids in the presence of specific bacteria can lead to the production of auto self-reactive antibodies. Studies have shown that these antibodies can promote the development and progression of the colorectal tumor (Calle and Thun 6368).

The relationship between obesity and colorectal cancer

Obesity is one of the top environmental risk factors that are associated with the development and progression of colorectal cancer. Studies have shown that a large number of Omani populations are overweight and obese. In fact, obesity is considered as a symbol of health and affluence in some parts of the country and, therefore, cherished and sought after (Nooyi and Al-Lawati 1735). Excess body weight, as characterized by the body mass index, has been connected with numerous illnesses and incorporates individuals who have excess weight (BMI ≥ 25-29.9 kg/m (2)) or suffering from obesity (BMI ≥ 30 kg/m (2)) (Vrieling and Kampman 471).

Excess weight and corpulence are among the main causes of death across the globe, representing no less than 3 million deaths annually. Additionally, approximately 12 percent of colorectal incidences in the Western nations have been linked to excess weight and corpulence. Experimental studies show that obesity is linked to over one-third of the colorectal cancer cases in men, but the connection is less dependable in women (Okayama, Schetter and Harris 12). As a matter of fact, a 5 kg/m2 increment in the body mass index has been emphatically linked to the risk of colorectal cancer. Owing to the changing lifestyle and increased consumption of junk food, obesity levels have increased dramatically in the Sultanate of Oman. Without a doubt, the incidence of obesity has reached 30 percent with no sign of decreasing. While there is a wealth of information to support the connection between corpulence and colorectal cancer, the mechanism involved has not been completely explained and are likely to be interceded by an intricate system of biochemically and immunologically components generated by the fatty tissues (Guffey 19).

Lumeng, Bodzin and Saltiel has linked obesity to low-grade inflammatory conditions, which are directly associated with colorectal cancer (175). Remember unsaturated fats are the molecules upon which enzymes act for eicosanoid creation, and eicosanoids can cause proinflammatory passageways that encourage colorectal carcinogenesis (Lumeng, Bodzin and Saltiel 176). Empirical studies have indicated that roughly 60 percent of fat tissue cells express the phagocytic cell marker in corpulent rats, though just 15% of fat tissue cells from slim rats express the phagocytic cell marker. What’s more, fat tissue phagocytic cells display a proinflammatory, established phenotype in fat rats, while those from slim pests have an alternatively-initiated, mitigating phenotype (M2).

The results show that obesity is closely linked to pro-inflammatory phagocytic cell behavior. Given the tendency of fat tissue phagocytic cells to assume a seditious phenotype and the all-around portrayed connection between inflammation and colorectal cancer, it is likely that phagocytic cells assume an essential part in the link between obesity and colorectal cancer (Okayama, Schetter and Harris 13). Be that as it may, no studies have utilized control systems to specifically determine the role of fat tissue phagocytic cells in the development and progression of colorectal cancer. However, the current proof of the significant role of macrophage-actuated inflammations in the progression of the disease is enough to link obesity to colorectal cancer (Okayama, Schetter and Harris 14).

Following extreme fat buildup, malignancy growth necrosis factor alpha is created by fat tissue phagocytic cells and to a slighter level by adipocytes and pre-adipocytes. Even though malignancy growth necrosis factor alpha has been broadly linked with fat tissue, information on obesity-related malignancy growth necrosis factor alpha is starting to show up in many studies (Lumeng, Bodzin and Saltiel 178). For example, Majno and Joris reported a more than 70 percent upsurge in expression and convergence of malignancy growth necrosis factor alpha in the colon following four months of consuming high-fat calorie-dense food, which was associated with an elevation in β-catenin, the significant enabler of Wnt signaling (99).

Moreover, a study carried out by Onsorio-Costa and Carvalheira assessed the role of malignancy growth necrosis factor alpha on corpulence-induced colorectal cancer in rats. The study found out that consumption of high-fat calorie-dense food elevated the expression of the malignancy growth necrosis factor alpha in the colon, which was linked to increased number of cancerous growths and reduced apoptosis. When the malignancy growth necrosis factor alpha was repressed, there was a reverse effect. The inhibition of malignancy growth necrosis factor alpha reinstated the number of cancerous growth and apoptosis to a level similar to a lean rat (Onsorio-Costa and Carvalheira 12).

A latest clinical research analyzed malignancy growth necrosis factor alpha among 10 women who were approaching menopause before and after shedding off some weight. Weight reduction (10percent) was linked to a noteworthy reduction in malignancy growth necrosis factor alpha concentration which led to a decrease in colorectal inflammation (U.S. Cancer Statistics Working Group 55). Be that as it may, another study showed no change in the levels of malignancy growth necrosis factor alpha in corpulent patients or colorectal cancer patients compared to the control group. Likewise, there was no relationship reported amongst body mass index and circulating malignancy growth necrosis factor alpha and risk for colorectal cancer in colorectal benign tumor patients. Despite the fact that the clinical proof is moderately constrained, most of the latest controlled trials in rats uphold the role of malignancy growth necrosis factor alpha in corpulence-enhanced colorectal cancer (Onsorio-Costa and Carvalheira 17).

Prevention Measures

How to thwart colorectal cancer incidences caused by dietary factors

The Sultanate of Oman has the highest number of colorectal cancer incidence in the Gulf region. As already been established, most of these incidences are attributed to weight gain, changing eating habits and lifestyle, socioeconomic factors and low consumption of dietary fiber. The change in lifestyle and eating habits are linked to increased urbanization and globalization. High fat calorie-dense food and processed foodstuff are increasingly becoming common among the Omani population with children and adolescents being the greatest victims of unhealthy feeding habits. The vast majority of the urban residents, especially the working-class have become addicted on junk foods. These changes have prompted the Omani government to take necessary measures to arrest the situation given the ubiquity of non-communicable ailments attributed to bad eating habits.

In May 2009, the department of nutrition in the ministry of health came up with a healthy eating guideline. This was part of the government’s wide effort to combat malnutrition and micronutrient deficiency among the Omani population, as well as fighting obesity and non-communicable diseases. Despite publishing this report nearly 6 years ago, the unhealthy dietary trend has not changed. The majority are still consuming inundated greasy foods, processed energy giving foods, and fast foods, instead of normal nutrient rich foodstuff, for instance, vegetables and fresh fruits.

For this reason, increased public awareness is necessary to avert the situation. Awareness is defined as an understanding of the undertakings of others, which offers a standpoint for an own undertaking. Increased public awareness is necessary for the development of healthy eating habits and prevention of non-communicable diseases such as colorectal cancer. Increased public awareness can also help in doing away with retrogressive sociocultural practices in Oman that promote bad dietary habits and increased risk of obesity. Retrogressive cultures also include cultures that promote gender separation and restrict women movement. Moreover, the southerners who regard corpulence as a symbol of healthiness and affluence should be made aware of the dangers associated with it.

There should be a deliberate effort to promote indigenous food crops, which are rich in dietary fiber. The study has shown that Food rich in dietary fiber enhances fecal mass and, therefore, speeds up the peristalsis process and minimizes the period of exposure to carcinogenic elements. The government should also increase the production of fiber- rich foods, for instance, bran, whole wheat products, cereals produced from wheat bran and whole wheat product, crispy vegetables, grain products, grains, dried flour paste made from whole wheat, and rye powder. Fiber-rich foods are excellent in combating carcinogenic elements in the body. They provide an all-inclusive range of cancer-repellant plant compounds or phytochemicals. Additionally, food availability and accessibility should be enhanced. Food scarcity attributed to socioeconomic disparity also plays a huge role in the development and progression of colorectal cancer. Lastly, the government should promote the Bedouin way of life, which promotes the consumption of healthy traditional foods.

Conclusions and Recommendations

Conclusion

Colorectal cancer is the fourth most prevalent cancer in the Sultanate of Oman. With respect to gender, it is the second most predominant cancer among men and fourth most pervasive among women. The cancer incidences are attributed to weight gain, changing eating habits and lifestyle, socioeconomic factors and low consumption of dietary fiber. Even though there is no substantial proof regarding any sort of diet being a risk factor for colorectal cancer, a number of studies suggest that fruits and non-starchy vegetables are plausible shields against colorectal cancer, while excessive consumption of meat and salts are possible risk factors. Food rich in dietary fiber enhances fecal mass and, therefore, speeds up the peristalsis process and minimizes the period of exposure to carcinogenic elements. However, the same studies also show that excessive consumption of fiber-rich foods such as pulses can increase the risk of colorectal cancer. For example, the upsurge in colon cancer incidence among the Asian immigrants in the United States is attributed to Soy, which is considered as the foundation of most Asian diets.

In addition, studies have linked colorectal cancer colorant pigment (haem) found in red meat. When haem is metabolized in the stomach, it releases N-nitroso compounds. N-nitroso compounds have been found to be very harmful to the cells lining the colorectal pathways. Haem is also known to stimulate rapid cell division. Additional cell division often elevates the odds of development and progression of colorectal cancer, on the grounds that each time a cell divides, it risks making a duplicating mistake in its DNA.

Last but not least, obesity is one of the main risk factors that are linked to the development and progression of colorectal cancer. Experimental studies show that obesity is associated with over 30 percent of the colorectal cancer cases in men. Whereas there is a wealth of information to support the association between obesity and colorectal cancer, the mechanism involved has not been totally expounded and are likely to be interceded by an intricate system of biochemically and immunologically components generated by the fatty tissues. Nonetheless, most of the latest controlled trials in rats uphold the role of malignancy growth necrosis factor alpha (originating from the white fatty tissues) in corpulence-enhanced colorectal cancer.

Recommendation

As it has been mentioned in chapter 4, the government should increase public awareness on the dangers of unhealthy dietary habits and corpulence which are cherished and desired in some parts of the country. The awareness should also include education on healthy diets and proper cooking of red meat. Studies show that overcooked increases the risk of recurrence of cancer, including colon and rectal cancer by 17 percent at 95% confidence level. Last but not least, individuals living in the countryside should be encouraged to continue with their Bedouin way of life, which is known to promote the consumption of healthy traditional foods.

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