Rising Incidences of Breast and Colon Cancers
Recent reports have shown an increase in the incidence of breast and colon cancers in several regions around the world.
The reasons behind these rising cancer rates are a topic of intense investigation among the world’s leading cancer researchers.
We know the answer is multifactorial: an increase in diets with more processed foods and reduced fiber, sedentary lifestyles, and even exposure to pollution and artificial light. 1
Perhaps the most obvious explanation points to the role of obesity and metabolic syndrome, conditions which have been associated with driving cancer risk through increasing inflammation throughout the body and causing the dysregulation of key hormonal pathways.

Factors Driving Trends in Breast and Colon Cancers
A few factors are driving these trends, and public health experts are focusing on them closely. Here’s a breakdown of some key points:
Breast Cancer
- Rising Rates in Younger Women
There has been an uptick in breast cancer diagnoses among younger women, particularly in their 30s and early 40s. This trend is most noticeable in high-income countries. While the overall incidence of breast cancer is still highest in older women, these rising rates in younger populations are concerning.
The reasons behind this include lifestyle factors (such as increased alcohol consumption, obesity, and lower rates of breastfeeding) and changes in reproductive patterns (later pregnancies, fewer children). 2
- Global Trends
The global burden of breast cancer has been increasing, with more cases being diagnosed in low- and middle-income countries as well, where access to early screening and treatment may be more limited. In these regions, breast cancer often presents at a later stage, which contributes to poorer outcomes.
- Impact of Screening and Awareness
In countries with advanced healthcare systems, early screening and awareness campaigns have led to better detection rates, which might partially explain the increase in diagnoses. However, this does not negate the overall rising trend, which suggests environmental and genetic factors are also at play.
Colon Cancer
- Increasing Incidence in Younger Populations: Like breast cancer, colon cancer has seen a concerning rise among younger individuals, particularly in people under 50. In the past, colon cancer was mostly diagnosed in older adults, but this is shifting. The American Cancer Society, for example, has observed that the incidence of colorectal cancer (CRC) among people aged 20–49 has been steadily increasing. 3A major factor here is likely the westernized lifestyle—poor diet (high in processed foods, red meat, and low in fiber), sedentary behavior, and increasing rates of obesity. In addition, genetic factors and the rise in inflammatory bowel diseases (such as Crohn’s disease and ulcerative colitis) also contribute to higher risks. 4
- Public Health Response: To address these trends, there has been a push to lower the recommended age for routine colon cancer screening. In the past, screenings typically began at age 50, but recent guidelines recommend starting at age 45 for individuals at average risk, due to the increasing rates of colon cancer in younger populations. 5
Environmental and Lifestyle Factors
A major contributor to the increasing rates of colon cancer is the growing consumption of high-fat, low-fiber diets, especially in developed countries. Additionally, sedentary lifestyles, smoking, and alcohol use are significant contributors. 6
There is ongoing research into the role of gut microbiota, inflammation, and the environment in the development of colon cancer, as well as studies exploring the genetic predispositions to the disease.
Advancing Awareness, Treatment and Prevention to Lower Cancer Rates
- Awareness and Education: Awareness campaigns are focusing on the importance of early detection through screening, especially for those at higher risk.
- Advances in Treatment: For both breast and colon cancers, there have been significant advancements in targeted therapies and immunotherapies, improving survival rates for many individuals.
- Prevention: Public health officials continue to push for lifestyle changes—promoting healthy eating, regular physical activity, and reducing alcohol and tobacco use—as strategies to lower cancer rates.
“Cancer mortality can be significantly reduced in the next few decades if we choose to focus our efforts on the prevention and early detection of the disease.” ~ Richard Béliveau Ph.D. Scientific Director, Chair in Cancer Prevention and Treatment, UQAM
Conclusion
The rise in breast and colon cancer incidences is multifactorial, including lifestyle changes, better detection, and possibly environmental and genetic factors. Public health initiatives and promoting lifestyle and nutrition changes are crucial to addressing this issue.
For nutritional cancer support contact Marsha Fenwick, C.N.P. R.R.T., and Certified Cancer Coach.
References:
- The Guardian. (2025). Ultra-processed food, ‘forever chemicals,’ and declining birth rates: What’s behind rising cancer rates in the under 50s? Retrieved from https://www.theguardian.com/science/2025/jan/26/ultra-processed-food-forever-chemicals-declining-birth-rates-whats-behind-rising-cancer-in-the-under-50s
- Society for Women’s Health Research. (n.d.). Rising breast cancer rates among younger women: Trends, risk factors, and racial disparities. Retrieved from https://swhr.org/rising-breast-cancer-rates-among-younger-women-trends-risk-factors-and-racial-disparities
- Yale Medicine. (n.d.). Colorectal cancer is on the rise among young people. Here’s why. Retrieved from https://www.yalemedicine.org/news/colorectal-cancer-in-young-people
- 6. City of Hope. (n.d.). What’s behind rising colorectal cancer rates in young adults? Retrieved from https://www.cityofhope.org/whats-behind-rising-colorectal-cancer-rates-in-young-adults
- UC Davis Health. (2024). Colon and rectal cancer on the rise in young adults. Retrieved from https://health.ucdavis.edu/news/features/colon-and-rectal-cancer-on-the-rise-in-young-adults-/2024/03
Marsha Fenwick, C.N.P. R.R.T.
Marsha is not your typical nutritionist. She began her career 20 years ago as a Registered Respiratory Therapist. Later, she earned her certifications as a Registered Nutritional Consultant Practitioner, Certified Nutritional Practitioner, and Registered Orthomolecular Health Practitioner. Marsha is also a Certified Cancer Coach. Her clinical practice specializes in: sustainable healthy weight loss, digestive health, women's hormones, diabetes, heart health, and cancer prevention and recovery. For more information and to book a FREE 15 minute consultation go to www.marshafenwicknutrition.com
