Researchers analyzed global data from 1990 to 2021 to understand how colorectal cancer affects people aged 65-74 years old. They found that while fewer people are dying from this cancer thanks to better treatments, new cases are still increasing in many parts of the world—especially in middle-income countries and East Asia. The study also identified that not eating enough milk-based foods is a major risk factor. These findings suggest that different regions need different strategies to prevent and treat colorectal cancer in this age group.

The Quick Take

  • What they studied: How colorectal cancer (cancer of the large intestine) affects people aged 65-74 worldwide, including how many people get it, how many die from it, and what factors increase the risk.
  • Who participated: This wasn’t a study with individual participants. Instead, researchers analyzed health data collected from countries around the world over 31 years (1990-2021) to understand global trends in colorectal cancer.
  • Key finding: Deaths from colorectal cancer dropped by about 20% between 1990 and 2021 in people aged 65-74, which is great news. However, the number of new cases increased slightly overall, with bigger increases in middle-income countries and East Asia. Men showed increasing rates while women showed decreasing rates.
  • What it means for you: If you’re in this age group, the good news is that treatments are working better and more people are surviving. However, prevention remains important, especially in developing regions. Eating more dairy products like milk and cheese may help reduce your risk.

The Research Details

This research used a special type of analysis called a ‘global burden of disease study.’ Instead of following individual people over time, researchers gathered health information that countries had already collected and organized it to see patterns across the world. They looked at data from 1990 all the way to 2021, tracking how many people got colorectal cancer, how many died from it, and how many were living with it. They also used mathematical models to predict what might happen through 2050.

The researchers paid special attention to people aged 65-74 because this group is important: they’re old enough to get colorectal cancer frequently, but they’re usually healthy enough to handle cancer treatments well. The study examined differences between countries based on their wealth level (high-income, middle-income, and low-income countries) and different geographic regions.

To understand what causes colorectal cancer, they looked at major risk factors like diet, smoking, and obesity. They used a statistical method called ’estimated annual percentage change’ to measure whether rates were going up or down over time.

This type of research is important because it shows us the big picture of a disease across the entire world. Individual studies might only look at one country or one hospital, but this approach helps us understand global trends and identify which regions need the most help. By projecting trends into the future, it helps governments and health organizations plan resources and prevention programs.

This study used data from the Global Burden of Disease database, which is one of the most comprehensive health databases in the world, compiled by the World Health Organization and other major health organizations. The strength of this research is its global scope and long time period. However, the quality of data depends on how well each country reports its health information, so some regions may have more accurate data than others. The study is descriptive (showing what happened) rather than experimental (testing a new treatment), which means it can show us patterns but can’t prove that one thing directly causes another.

What the Results Show

Between 1990 and 2021, the number of new colorectal cancer cases in people aged 65-74 increased slightly from 125 cases per 100,000 people to 136 cases per 100,000 people. This might sound like a big jump, but it was actually a very small increase of about 0.1% per year. However, this overall small increase hides important differences: men’s rates went up by 0.39% per year, while women’s rates actually went down by 0.36% per year.

The really good news is about deaths. Deaths from colorectal cancer dropped significantly from 73 deaths per 100,000 people in 1990 to 58 deaths per 100,000 people in 2021. This represents a decline of about 1% per year, meaning that better screening and treatment are saving lives.

Geographically, the story varies widely. High-income countries like Australia, Canada, and the United States saw the biggest improvements in survival rates. Middle-income countries and East Asia, however, saw the biggest increases in new cases. This suggests that as countries become wealthier and people live longer, colorectal cancer becomes more common—but these countries may not yet have the screening and treatment programs that wealthy nations have developed.

The study found that the number of people living with colorectal cancer (prevalence) is expected to keep growing through 2050, even as death rates continue to decline. This means more people will be cancer survivors. The leading risk factor for colorectal cancer in 2021 was not eating enough milk and dairy products. Other important risk factors included smoking, obesity, and low fiber intake. The research showed that countries with higher socio-demographic development (wealthier, more educated populations) generally had better outcomes.

This research confirms what other studies have shown: colorectal cancer is becoming more common in developing countries as they modernize, while wealthy countries have successfully reduced death rates through screening programs like colonoscopies and improved treatments. The finding about dairy products aligns with previous research suggesting that calcium and vitamin D in milk may protect against colorectal cancer. The gender difference (men having higher rates) is consistent with other global cancer studies.

This study analyzed existing data rather than conducting new experiments, so it can show us trends but can’t prove cause-and-effect relationships. The quality of data varies by country—some nations have excellent health tracking systems while others have less detailed records. The projections to 2050 are based on mathematical models that assume current trends will continue, but unexpected changes (like new treatments or lifestyle shifts) could change these predictions. The study doesn’t explain why men and women have different trends, which would require additional research.

The Bottom Line

For people aged 65-74: (1) Get regular colorectal cancer screening as recommended by your doctor—this is the most effective way to catch cancer early when it’s most treatable (HIGH confidence). (2) Eat more dairy products like milk, yogurt, and cheese, as the research suggests this may reduce risk (MODERATE confidence). (3) Maintain a healthy diet with plenty of fiber, avoid smoking, and maintain a healthy weight (HIGH confidence, based on general cancer prevention knowledge). (4) If you live in a middle-income country, advocate for better access to screening programs in your region (MODERATE confidence that this would help).

This research is most relevant for people aged 65-74 and their doctors. It’s also important for public health officials in middle-income countries and East Asia who are seeing rising colorectal cancer rates. Healthcare systems should use this information to plan screening and treatment programs. Younger people should also pay attention because the trends suggest colorectal cancer will remain a significant health issue. People with family histories of colorectal cancer should be especially attentive to screening recommendations.

If you start eating more dairy and following screening recommendations, you won’t see immediate results. Cancer prevention is a long-term strategy. Regular screening can detect cancer early, potentially within months to a year. If you’re diagnosed and treated, survival rates have improved significantly—many people now live for years or decades after treatment. The global trends shown in this study developed over 31 years, showing that changes happen gradually.

Want to Apply This Research?

  • Track dairy intake daily: log servings of milk, yogurt, cheese, or other dairy products. Aim for 2-3 servings per day and monitor whether you’re meeting this goal. Also track screening appointments and results to ensure you’re staying current with recommended colorectal cancer screening.
  • Set a daily reminder to include one dairy serving at meals (milk with breakfast, yogurt as a snack, cheese with lunch). Use the app to log these foods and see your weekly dairy intake pattern. For screening, set an appointment reminder based on your doctor’s recommendations (typically every 10 years for colonoscopy if results are normal).
  • Use the app to track dairy consumption weekly and monthly to identify patterns. Set annual reminders for colorectal cancer screening conversations with your doctor. If you have risk factors (family history, smoking, obesity), increase monitoring frequency and share data with your healthcare provider to discuss personalized prevention strategies.

This research provides important global health information but should not replace personalized medical advice. Colorectal cancer screening recommendations vary based on individual risk factors, age, and medical history. Please consult with your healthcare provider about whether screening is appropriate for you and which screening method is best. If you have symptoms like blood in stool, persistent abdominal pain, or changes in bowel habits, seek medical attention promptly. This article summarizes research findings and does not constitute medical advice or diagnosis.