- Diabetes and colorectal cancer have a strong link, although the reason they’re connected is still the subject of research.
- Diabetes and colon cancer share many of the same risk factors and disease pathways, making it easier to reduce the chances of getting either or both.
- At-home colon cancer tests, regular exercise, a higher-fiber diet, and other regular interventions can reduce your risk.
Diabetes and colorectal cancer are increasingly seen as linked. What do the studies tell us, and what can people with diabetes do to manage their risk of colon cancer? Here’s what you need to know.
Is There a Link Between Diabetes and Colorectal Cancer?
The evidence is increasingly pointing towards a strong link between diabetes and colon cancer. A 2014 survey of studies found that both cohort studies, which involve people who share a common characteristic over a long period of time, and case control studies found that the risk of colon cancer was up to three times as high for people with diabetes.
Considering the lifetime risk of getting colorectal cancer is 4.3% for men and 4% for women, that’s a considerable increase. Another study from around the same time found that obesity could also be a factor; a particular concern as the majority of people with diabetes are overweight or obese. Other cohort studies have found that diabetes may set the stage for early-onset colon cancer as well.
This doesn’t mean you’re guaranteed to get colon cancer if you’re diabetic or that diabetes is a direct cause of colon cancer. Both are common diseases, with one in ten Americans having diabetes. While colon cancer numbers have been steadily declining, about 106,000 new cases will be diagnosed in 2022.
There are also other risk factors for colon cancer, such as smoking, family history, and inflammatory bowel disease. Still, considering the risk, many doctors take a “better safe than sorry” approach. If you’re diagnosed with diabetes, you can generally expect to add colon cancer screenings to your annual battery of tests.
How Are Diabetes and Colon Cancer Linked?
Why diabetes raises your risk of colon cancer is an open question researchers are still working on. But there are some clues.
First, there’s the interplay between your insulin levels, your metabolism, and your body. For example, hyperinsulinemia, or too much insulin in your blood, is closely connected to both obesity and cancer, to the point where some doctors may use insulin tests as part of a cancer diagnosis.
Since body weight is seen as a risk factor for cancer, the connection may seem obvious. However, it’s not clear whether obesity is a direct cause of cancer, a symptom of another condition, or an indirect source of stress on the body that aggravates other risk factors. There’s a good chance that all of these factors play a role.
Similarly, people with diabetes have a higher risk of liver, endometrial, bladder, and breast cancer. Again, it’s not clear if this is due to the overall strain on the system from diabetes or whether there’s a direct cause, and It doesn’t apply to all cancers. Men with diabetes, for example, have a higher risk for high-grade prostate cancer but may have a significantly lower risk of low-grade prostate cancer.
However, there is evidence of a possible deeper connection between diabetes and some forms of cancer. A 2017 follow-up study on the topic notes that diabetes and cancer share some methods of harming the body, to the point where some drugs are tested both as cancer and diabetes-related treatments.
A 2020 study suggests that they may share pathways (ways that a specific disease makes you sick). More research is needed to understand how and why.
What Risk Factors Are Shared Between Colon Cancer and Diabetes?
Diabetes and colorectal cancer, as well as other forms of cancer, do overlap in terms of some possible key risk factors.
- A low-activity lifestyle. People who exercise less than three times a week have an elevated risk.
- Diet. Diets high in processed foods such as processed meats are particularly risky.
- Age. As we age, the possibility of all diseases rises, including cancers and diabetes.
- Family history. If you’ve got a family history of any disease, make sure your doctor knows. They will probably recommend regular testing.
- Tobacco use. Tobacco is a well-known risk factor for cancer, yet smokers also have a 30% to 40% higher chance of getting diabetes.
Remember that these are only risk factors, not guarantees you’ll get either or both, but lowering the odds is a smart move.
What Can I Do To Reduce My Risk of Diabetes and Colorectal Cancer?
While there’s no single action that can absolutely prevent any common disease, there’s plenty you can do to reduce your risk or catch it before it gets worse.
- If you’re prediabetic or diabetic, ask your doctor about cancer symptoms you should look out for.
- If you smoke, quit. Smoking cessation is one of the most effective things you can do for your overall health.
- Reduce or eliminate your alcohol consumption. Even moderate alcohol consumption can be a risk factor for a number of diseases.
- Add more activity to your day, such as regular walks or exercise classes.
- Eat a diet higher in vegetables, fiber, and unprocessed foods. Processed meat products, in particular, are indicated to be a risk for colorectal cancer.
- Develop a weight-reduction plan with your doctor or specialist. In many cases, increasing your exercise and eating more vegetables will help with weight loss, but it’s also important to set reasonable goals and consider how and where you eat.
- Get regular colorectal cancer screenings, either at your doctor’s or with an at-home colon cancer test. The wider availability of testing has made it easier than ever to catch colon cancer earlier and begin treatment.
Start Now to Manage Risk
Working to prevent risk for diabetes and colorectal cancer now will pay dividends in the future. Follow the eDrugstore blog for evidence-based information about at-home testing, lifestyle changes, men’s health issues like erectile dysfunction, and much more.
Dan is a long-time freelance writer focusing on technology, science, health, and medicine, with a lifelong interest in physics, biology, and medicine. His work has taken a particular focus on scientific studies “beyond the headlines,” reading the study to more closely examine the results.