Cancer Risk Factors


Cancer refers to a set of diseases that are marked by abnormal cell growth and cell duplication  due to various triggering factors, ranging from genetics and other diseases to lifestyle habits. 

Rapid cell replication often leads to the accumulation and formation of a mass of cells known as a tumour. A tumour can be either benign or malignant. A benign tumour is harmless and will not cause life-threatening complications, whereas malignant tumours may be fatal depending on their type, location of origin, and rate of spread. 

These malignant tumours are cancerous and lead to a variety of clinical symptoms that affect day to day activities and cause long term damage. Cells are usually programmed to undergo cell death (apoptosis) at a certain point. However, this does not occur during cancer.

Healthy lifestyle choices, such as proper nutrition, regular physical exercise, and general mental wellbeing, paired with regular health check-ups and knowledge about the signs, and symptoms can equip you with the knowledge to prevent cancer.1  


Nutrition refers to dietary intake for growth, development, and wellbeing within the body.  Research has demonstrated the importance of good nutrition in preventing cancer. 

Deficiencies of minerals and vitamins have a high risk of causing illness. Additionally, high sodium intake (salty foods), pickled vegetables, consumption of red and processed meat, fast food, and high sugar content food items have a higher risk of damaging our internal health systems and increasing the risk of cancer due to the carcinogenic capabilities of the components found in these foods. 

Conversely, fruits, leafy vegetables, whole grains (such as brown rice), lentils, and nuts can improve your health and reduce the risk of developing serious health problems.2 For more information on nutrition myths, as well as preventing cancer, click here.  

Physical Activity  

Not all cancers are preventable. However, exercise can function as a preventive measure and improve our general health. Physical activity can reduce the risk of mental illnesses such as major depressive order, dementia, heart diseases, osteoporosis and other bone problems.

 In addition, maintaining a healthy weight reduces the risk of obesity and, most importantly, the risk of cancer. It does so by reducing hormone levels that dictate rapid cell division and replication, improving the immune system, reducing inflammation (our body’s response to damage, often causing fever, cell damage, and scar tissue if left untreated) and by improving digestive, respiratory, nervous, and pulmonary health. 

If you lead a sedentary lifestyle, making small but regular changes is vital to incorporate a new and healthier way of living. This can be as simple as walking or cycling or taking part in any other activities that will help you remain motivated, active, and healthy.  


Smoking and cancer incidence have a strong correlation. There are no ‘safe’ levels of tobacco  use. It has a variety of toxins and carcinogens, which are cancer-causing agents. These can create problems throughout the body by damaging cells and the DNA within these cells. Cancers occur when carcinogens bind to the DNA, thereby damaging it and causing cells to divide and replicate abnormally. These cancerous growths can then spread throughout the body (known as metastasising). 

The toxins in tobacco can immunise the immune system, decreasing the body’s capacity to fight cancer. In particular, smoking primarily increases the risk of oral, oesophageal, lung, larynx, stomach, colon, and pancreatic cancers.3 


High levels of alcohol consumption are associated with a heightened risk of developing cancer.  Alcohol has the potential to increase the risk of liver, mouth, oesophageal, colon, rectum, breast,  gut, and pancreatic cancers. 

Alcohol, upon entering the bloodstream post-consumption, can cause DNA damage. It can release toxic chemicals when the body breaks down the chemical components of alcohol (ethanol). It can also increase the hormone levels in the body. These  hormones can dictate rapid cell growth and affect the balance of fluid systems within the body (homeostasis). 

Chronically decreased homeostasis can have long-term ill effects on the body. Alcohol is also known to cause DNA mutations within the cells after causing irritations and inflammation in the tissues. When attempting to repair the inflammation, the body’s responses are subdued by the chemicals in alcohol. 

Additionally, it decreases the nutrient-absorbing capabilities of the body, thereby causing decreased nutrition in the cells. This also leads to vital mineral and vitamin deficiencies. It also increases the risk of cardiovascular disease and obesity which can further contribute to the risk of cancer.4 


Sleep disorders, in combination with other factors, have the potential to contribute to an increased risk of cancer. Sleep disorders include insomnia, sleep disturbances, sleep apnoea, sleepwalking, and sleep hypoxia.

 Poor sleep can impact the secretion of the hormone melatonin, which affects our circadian rhythms (24-hour body clock) and can decrease our immunity to diseases. Sleep disorders are linked with an increased risk of oesophageal, stomach, squamous cell and breast cancers. 

Disruptions in regulatory cycles, coupled with weakened immunity, promotes the growth and progression of tumours via uncontrolled rapid and abnormal cell division.5 This is an emerging research area, with much left to explore. 

However, the take-away point is the importance of sleep in not only preventing cancer, but also promoting generalised health and wellbeing at the physical and mental levels. 


Obesity and being overweight do not always result in cancer. However, it does increase the risk of developing cancer over time. Obesity, weight changes, and body fat distribution have been associated with 20% of all the cancers as causative agents.6 

The association between cancer and obesity can be primarily determined by lifestyle choices and  anthropometric measurements. Anthropometrics (measuring the body) look at weight gain, body fat, visceral fat, and body mass index, while lifestyle factors include lifestyle and dietary habits, such as a lack of exercise and a highly calorific diet. These further cause hormonal imbalances, reduce the important activities of chemical components within the body and affect regulatory cell functioning. They can also cause inflammation, cell death, cell damage, and other problems throughout the body.7  


It is not often possible to determine the exact cause of cancer, however, it is important to note the risk factors, such as the ones discussed above, that can influence the incidence and prevalence of cancer.

Owing to years of epidemiological research, it is now possible to identify certain risk factors and implement associated preventive measures. It is important to take these risk factors into consideration and gain as much knowledge as possible about what you can do to prevent cancer and lead more fit and healthy lives. 


  1. Roy, P. S., & Saikia, B. J. (2016). Cancer and cure: A critical analysis. Indian journal of cancer,  53(3), 441–442.
  2. Key, T., Bradbury, K., Perez-Cornago, A., Sinha, R., Tsilidis, K., & Tsugane, S. (2020). Diet,  nutrition, and cancer risk: what do we know and what is the way forward?. BMJ, m511. 
  3. Hermans, K. E., van den Brandt, P. A., Loef, C., Jansen, R. L., & Schouten, L. J. (2021). Alcohol  consumption, cigarette smoking and cancer of unknown primary risk: Results from the  Netherlands Cohort Study. International Journal of Cancer, 148(7), 1586-1597. 
  4. Bagnardi, V., Rota, M., Botteri, E., Tramacere, I., Islami, F., Fedirko, V., Scotti, L., Jenab, M.,  Turati, F., Pasquali, E., Pelucchi, C., Galeone, C., Bellocco, R., Negri, E., Corrao, G., Boffetta,  P., & La Vecchia, C. (2015). Alcohol consumption and site-specific cancer risk: a  comprehensive dose-response meta-analysis. British journal of cancer, 112(3), 580–593. 
  5. Brzecka, A., Sarul, K., Dyła, T., Avila-Rodriguez, M., Cabezas-Perez, R., Chubarev, V. N.,  Minyaeva, N. N., Klochkov, S. G., Neganova, M. E., Mikhaleva, L. M., Somasundaram, S. G.,  Kirkland, C. E., Tarasov, V. V., & Aliev, G. (2020). The Association of Sleep Disorders, Obesity  and Sleep-Related Hypoxia with Cancer. Current genomics, 21(6), 444–453. 
  6. Calle, E. E., & Kaaks, R. (2004). Overweight, obesity and cancer: epidemiological evidence and  proposed mechanisms. Nature Reviews Cancer, 4(8), 579-591
  7. De Pergola, G., & Silvestris, F. (2013). Obesity as a major risk factor for cancer. Journal of  obesity, 2013, 291546. 

Ishana Gole

Master of Science - MS, Bioscience Entrepreneurship, UCL (University College London)
Ishana is a Biomedical Science student with a keen interest in neuroscience and past experience in online consulting, marketing and advertising. presents all health information in line with our terms and conditions. It is essential to understand that the medical information available on our platform is not intended to substitute the relationship between a patient and their physician or doctor, as well as any medical guidance they offer. Always consult with a healthcare professional before making any decisions based on the information found on our website.
Klarity is a citizen-centric health data management platform that enables citizens to securely access, control and share their own health data. Klarity Health Library aims to provide clear and evidence-based health and wellness related informative articles. 
Klarity / Managed Self Ltd
Alum House
5 Alum Chine Road
Westbourne Bournemouth BH4 8DT
VAT Number: 362 5758 74
Company Number: 10696687

Phone Number:

 +44 20 3239 9818