Cancer is one of the most predominant non-communicable diseases globally despite the improvements in life expectancy, living standards, and healthcare access. There has been an increase in cancer mortality by 40% over the past 50 years, and this is estimated to increase to 60% over the next 20 years.
Out of the various cancers, colorectal cancer (CRC) is the third most common cancer worldwide. It is a slow-onset tumor in the large intestine or the rectum. The highest prevalence is seen in developing nations due to adopting a westernized lifestyle. CRC is normally associated with the risk factors such as increased age, male gender, and positive family history. However, recently the increased prevalence of CRC is contributed by unhealthy dietary habits, smoking, alcohol consumption, and a sedentary lifestyle.
Diet and Colorectal Cancer:
An unhealthy diet causes offensive actions against the colon and rectum. Consumption of red and processed meat has elevated the risk of CRC as these foods contain carcinogens such as N-nitroso compounds formed by fats and omega six. In addition, different modes of cooking like smoking, curing, and cooking meat at really high temperatures can contribute to the occurrence of CRC. Therefore, according to Public Health England, it is best to improve the diet by limiting the consumption of red and processed meat to 500 grams per week to reduce the incidence of CRC and to avoid these modes of cooking. Additionally, a prudent diet containing 10% fiber, 300mg calcium, and vitamin D should be adopted daily as it promotes good bowel activity.
Sedentary lifestyle and Colorectal Cancer:
This is commonly witnessed in developed nations like the UK and USA. However, it is now seen in developing nations like India. A sedentary lifestyle causes inflammation of the large intestine and the release of carcinogens. It is estimated that there is 25% less risk of developing CRC in active individuals in contrast to 50% elevated risk in sedentary people. Therefore, it is advisable to educate the public about the importance of physical activity such as a brisk walk for 5 hours a week and daily exercise for 30 minutes as this will reduce the risk of CRC drastically.
Smoking and Colorectal Cancer:
Smoking was one of the most predominant causes of CRC but there has been a reduction in the prevalence of smoking from 1980 to 2013 due to the firm smoking policies adopted by developed nations. However, there has been an increase in smoking in underdeveloped and developed nations. Smoking causes molecular abnormalities and carcinogenesis in the large intestine. Many studies have proved that non-smokers have higher life expectancy than former and current smokers.
Alcohol and Colorectal Cancer:
Consumption of alcohol at moderate to high levels elevates the risk of CRC. Alcohol causes lots of calamitous consequences in the large intestine by developing harmful by-products and immunological changes. It is estimated that individuals who consume two to three drinks per day have a 20% risk of CRC whereas individuals who consume more than three drinks show an elevated risk of 40%.
Action against Colorectal Cancer:
WHO has developed policies to combat the rising incidence of CRC by raising awareness about healthy lifestyle options and adopting different screening tests such as colonoscopy, sigmoidoscopy, faecal occult blood test, faecal immunochemical test, and double contrast barium enema. They have advised the healthcare systems of every nation to act before it’s too late.
Dr Michael Oludipe who worked as a resident medical officer in the Oncology Department at Federal Medical Center Abeokuta, Nigeria, follows the WHO policies and advises the public to adopt a healthy lifestyle, be aware of their bowel habits, make a habit to move their bowels once a day and advises colonoscopy after the age of 50 years. He said that these interventions have reduced the incidence of CRC in the region. Fortunately, these initiatives have been showing immense success not only in Nigeria but globally too which proves there are still hopes to change the future statistics of CRC for the better.
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