Cancer and lifestyle – research round up

Park SY et al. Alcohol Intake and Colorectal Cancer Risk in the Multiethnic Cohort Study. Am J Epidemiol. (2018) Sep 15 DOI: 10.1093/aje/kwy208  https://thescpn.org/2CrDtb7

The WCRF reported convincing evidence that alcohol is a risk factor for colorectal cancer (CRC) above 30g per day. Due to homogeneity in previously studied populations limited evidence existed for different ethnic groups. This study investigated the association between alcohol and risk by ethnicity, gender and lifestyle factors (n=215, 000). An increased risk of CRC was identified in drinkers (>15g/day) of all ethnicities other than Afro Americans, as well as underweight individuals and those with a lower fibre and folate intake confirming the findings of the WCRF.

Conclusion: Individuals of all ethnicities are at greater risk of cancer if they consume alcohol and that risk increases according to the amount and frequency of drinking.

Wiseman M. Nutrition and cancer: prevention and survival. British Journal of Nutrition Epub ahead of print DOI:10.1017/S0007114518002222 https://thescpn.org/2PsjQ5L 

More and more the evidence points to cancer as a disease process which may begin many years before symptoms. With regard to nutrition and cancer it is becoming clearer that it is the whole set of nutritional exposures over our lifetime that determines the individual’s susceptibility to exogenous and endogenous carcinogenic exposures. The protection of our body from these exposures depends  on the oxidative metabolism and healthy cell regeneration but this process may be impoverished by poor nutrition and ageing. The WCRF have identified modifiable lifestyle behaviours which impact on cancer risk but increasingly it is being recognised that each risk factor does  not act in isolation and it is a patter n of diet and activity conforming to the WCRF recommendations that helps to reduce risk of several cancers and of total mortality.

Conclusion: It is important to adhere to as many WCRF guidelines as possible to minimise the risk of developing cancer.

Song M. et al. Cancer prevention: Molecular and epidemiologic consensus Science 361 (6409), 1317-1318 DOI: 10.1126/science.aau3830 https://thescpn.org/2EhUgPM

The authors of this paper argue that decreases in cancer mortality have lagged behind those of cardiovascular disease, another preventable disease despite there being a body of strong evidence that exposure to environmental and lifestyle risk factors impacts on cancer risk. This is attributable to a lack of funding for cancer prevention, only 2 to 9% of global cancer research funding is in cancer prevention, with  treatments for established cancer being favoured for ease of conducting research, financial reasons and an emphasis on reaction rather than proaction. More research is needed into epidemiology and molecular biology to identify the mechanisms through which diet, exercise, and other lifestyle factors that are unambiguously associated with cancer lead to the disease. Further research will hopefully discover additional preventable causes e.g. early-life exposures, allowing for the development of further guidance to reduce cancer mortality. In addition the authors argue for more behavioural and policy research into barriers to adoption of effective evidence-based interventions.

Conclusion: The authors envisage a 70% reduction in cancer mortality globally if the proposed research came to fruition, even without the development of any new therapies.