Cancer has long been associated with older age, but recent trends indicate a troubling increase in cancer rates among individuals under 50. This week, an investigative report by ABC 4 Corners suggests that chemicals, including plastics, might be contributing to this rise in early-onset cancers. But what does the evidence actually say about the causes of this increase, and what measures can be taken to mitigate these risks?
Understanding Cancer’s Age-Old Connection
Traditionally, cancer has been more prevalent among older adults. This is largely due to the accumulation of DNA mutations over time. Each cell in the human body contains DNA, which can be damaged or mutated, leading to uncontrolled cell growth and cancer. As we age, the likelihood of accumulating harmful mutations increases, partly because our bodies become less efficient at identifying and eliminating mutated cells. This explains why cancer is more common in older populations.
Environmental Factors in Younger Populations
The increase in cancer rates among younger people suggests the involvement of environmental factors that are not yet fully understood. Environmental factors encompass a wide range of external influences, including chemicals, viruses, bacteria, lifestyle choices, and diet. These factors can enhance the probability of DNA copying errors or directly damage DNA, thereby increasing cancer risk.
For instance, ultraviolet (UV) radiation from the sun is a well-known environmental factor that can lead to skin cancer, while smoking is linked to lung cancer. Public health campaigns have successfully reduced the incidence of these cancers in Australians under 50 over the past three decades. However, other cancers, such as those affecting the liver, pancreas, prostate, breast, and kidney, are on the rise among young people, particularly in wealthier, Western nations.
The Spotlight on Chemicals
Researchers are increasingly focusing on chemicals as a potential cause of rising cancer rates. Modern life exposes individuals to more chemicals than previous generations, including air pollutants, food additives, and plastics. While many chemicals linked to cancer are typically found in industrial settings, plastics are ubiquitous, making them a significant concern for public health.
Experts agree that plastics pose a substantial risk to both human health and the environment. However, pinpointing specific plastics responsible for particular health issues, including cancers, is challenging due to the vast number of different plastics in use. Animal studies can provide strong evidence, but the complexity of human exposure to numerous environmental factors complicates the identification of definitive links between specific chemicals and cancer types.
Case Study: Colorectal Cancer in Young Adults
Colorectal cancer, or bowel cancer, serves as a pertinent example. While rates of bowel cancer in older adults are decreasing, thanks in part to improved screening and early detection, early-onset cases are rising. Some researchers speculate that increased exposure to plastics may play a role, as the digestive system is directly exposed to these substances through food consumption.
Potential culprits include nano- or micro-plastics and chemicals such as PFAS (per- and poly-fluoroalkyl substances) that can leach from plastics into food. Other factors, such as diet, lifestyle, obesity, and alcohol consumption, are also correlated with increased cancer rates. Additionally, the microbiome, or the types of bacteria in the digestive system, may influence bowel cancer risk, with certain bacterial toxins linked to higher risk levels.
Mitigating Cancer Risks
While definitive evidence linking chemicals to increased cancer risk in young people is still lacking, ongoing research in this area is crucial. Reducing exposure to plastics and other potentially harmful chemicals is advisable for overall health. Additionally, maintaining a healthy lifestyle through regular exercise and a balanced diet can help lower cancer risk.
Individuals with concerns, especially those with a family history of cancer, should consult healthcare professionals for personalized advice. As research continues, funding from organizations such as Cure Cancer Australia and Cancer Council Victoria supports efforts to uncover more about these complex relationships.
Sarah Diepstraten and John (Eddie) La Marca, both involved in cancer research, emphasize the importance of continued investigation into environmental factors and their potential links to cancer. La Marca is affiliated with the Olivia Newton-John Cancer Research Institute and the Walter and Eliza Hall Institute of Medical Research, highlighting the collaborative effort required to address this public health challenge.
