Colon cancer is the fourth most common cancer in both men and women and is the second most common cause of cancer deaths in the US. Both men and women have about a 1 in 24 chance of developing colorectal cancer. In 2022, it’s estimated that there will be over 106,000 new cases of colon cancer in the US.
The good news is that there has been an overall downward trend in the number of new colon cancer cases since the mid-1980s. This is most likely due to more folks getting screened, as well as improvements in risk factors such as fewer people smoking and we’re eating less processed meats. Unfortunately though, during this same time, there has been a rising trend among a younger demographic, with a 2% increase in cases every year in those under 50.
On the rise among folks under 50
While the incidence of colon cancer, in general, has been declining over the past couple of decades, the incidence among folks under the age of 50 has been rising. It’s now the most commonly diagnosed cancer and the most common cause of cancer death in men under 50. Because of this steady rise, the US Preventative Services Task Force lowered the recommended screening age from 50 to 45 in 2021.
So, the idea that colon cancer is something only “old people” need to think about needs to change. It also drives home the importance of paying attention to preventive measures no matter how old you are. Remember, issues like colon cancer or dementia don’t happen overnight, they take years—decades even—to develop. Healthy lifestyle habits in your teens, 20s, and 30s help set the stage for healthy aging. And research backs this up, with some studies suggesting that getting adequate amounts of nutrients like folate and omega-3s as much as 16 years before a diagnosis is associated with a reduced risk of developing colon cancer.
Diet’s role in colon cancer
Most of the following foods and nutrients have demonstrated a positive role in either the prevention or development of colon cancer. Making sure they are a regular part of your diet, and avoiding those that may be harmful, could help tamp down the disturbing rise in colon cancer cases we’re currently seeing in that younger demographic.
Studies have found a pretty decent association between calcium intake and colon cancer risk—as much as a 70% lower risk in one large study. This may be due to calcium’s role in inhibiting cell proliferation, promoting cell apoptosis, suppressing oxidative damage, and modulating cell signaling pathways related to colon cancer. Ideally, you’re getting in at least 700-1,000mg of calcium a day—benefits may level off at about 1,200mg per day. Preferably through your diet.
While it’s not a sure thing, there is certainly compelling research showing promise for potential chemopreventive effects of vitamin D against the development of colon cancer. (As a side note, a lot of the studies referenced here are looking at both vitamin D and calcium.) Researchers aren’t quite sure how vitamin D is helpful, however—it could be the result of any of the various anticancer activities vitamin D plays like influencing the expression of some genes that control the life cycle of cells, assisting in tamping down inflammation and helping to stop the growth of new blood vessels in tumors. Research suggests you should maintain a 25 (OH)D plasma level of at least 36 ng/mL. Keeping a regular eye on your levels is easy with this test.
Most studies have shown that a diet higher in fiber may be associated with a reduced risk of colon cancer. This could be thanks to a number of beneficial impacts fiber has like helping to mop up carcinogens in the gut, decreasing transit time, and feeding gut bacteria so they can produce beneficial short-chain fatty acids (SCFAs). It’s important to note that all fiber is not necessarily created equal. Some studies suggest that the source of fiber matters when it comes to colon cancer, with more potential benefits from the fiber found in cereals, whole grains, and fruit. Aim for 25g/day for women and 34g/day for men.
When it comes to meat and colon cancer, there has been quite a bit of debate. Unfortunately, it seems like red meat is often lumped in with processed meats when looking at the potentially detrimental effects of this protein. More often than not, studies have shown a potential association between an increased risk of colon cancer with regular consumption of both red meat and processed meat. This connection has also been seen for colorectal adenomas—a type of polyp that can turn cancerous.
While folks almost always seem to be accepting of the risk posed by processed meats, the red meat-colon cancer connection is usually met with skepticism (and often downright anger). Regardless, there are some aspects of red meat that could help explain why it tends to fare unfavorably in these studies. It is rich in sulfur-containing amino acids, saturated fats, and heme iron which can cause oxidative stress and form potent carcinogenic compounds. Cooking meat at high temps (hello grill!) has also been shown to produce heterocyclic amines (HCAs) and other carcinogens.
So for anyone concerned with developing colon cancer or polyps, it may be wise to avoid processed meats altogether and reduce the amount of red meat in your diet to no more than a few ounces per week. Replacing red meat with poultry and fish—both of which are associated with a modest reduction in colon cancer risk—can be a healthy alternative.
Research has had some mixed results on dairy’s effect on colon cancer risk, but if you can tolerate it, it may still be worth adding to your diet. Even though studies have been inconsistent with most dairy products, the research does seem to lean in the direction of a positive benefit. Studies do seem to suggest that high-quality dairy is key. If you choose to eat fermented products like yogurt, it shouldn’t be heat-treated and should contain high counts of live bacteria. Regularly eating fermented dairy products can help boost the number of Bifidobacteria in your gut. This can help increase the production of butyrate. Butyrate is a short-chain fatty acid that fuels the cells of the gut lining, supports immune function, and helps tighten up the lining of your gut.
If you opt for dairy, aim to eat a variety of products—cheese, milk, yogurt—not just one source. There may be more benefits to eating a variety of sources. One study suggests that to get the biggest potentially protective bang for your buck, shoot for about 2 cups of milk or yogurt per day.
Fruits & veggies
When it comes to the most nutritious foods available, fruits and vegetables are usually at the top of the list. And while there’s no question that they have a positive effect on overall health, just how big of an impact they have on colon cancer isn’t quite as clear. Research results are mixed with some studies showing no association between fruit and veggie intake and colon cancer risk.
While some studies do show fruits and veggies may have a positive impact on your risk of developing colon cancer, even these suggest that in terms of colon cancer, there isn’t a huge benefit to eating a ton of veggies. The key is to make sure you at least eat some each day. Eating about 3.5 ounces of fruit and between 3.5 and 7 ounces of veggies per day may provide the greatest reduction of risk. While eating more than this has other health benefits, it doesn’t look like there are any colon cancer-specific benefits above this amount.
While folks often point to the fiber in grains as the most beneficial COMPONENT when it comes to colon cancer prevention, studies are actually mixed on how beneficial fiber actually is. Regardless, properly prepared whole grains contain a number of beneficial components such as vitamins, minerals, phenolic compounds, phytic acid, tannins, and enzyme inhibitors that may actually help reduce colon cancer risk. Research suggests that 90g a day of whole grains may reduce colon cancer risk by about 15%.
If you decide to add whole grains to your diet, look for sprouted varieties. Sprouting grains, like oats, can make these foods even more beneficial by ramping up their antioxidant and anti-inflammatory properties.
Thanks to being rich in beneficial phenolic compounds, drinking coffee is often associated with a laundry list of health benefits. Research also suggests a regular coffee habit may help reduce the risk of developing not only colon cancer but other gastrointestinal cancers as well. It may even provide some protection against the development of adenomas—a polyp that has the potential to turn cancerous. (These are removed during colonoscopy screenings.)
Some studies have suggested that the more coffee you drink, the more benefits you could get. Others see more of a U-shaped relationship, with a decreasing benefit, and even increased risk, with heavier consumption. All in all, though, coffee lovers have reason to rejoice as it looks like topping out at 3 cups a day could make the biggest impact.
And these potential benefits appear to apply to both caffeinated and decaf coffee. Though decaf may actually be a healthier bet, especially if you drink more than two cups per day. If you decide to add coffee to your regular routine, caramel macchiatos and birthday cake lattes aren’t going to cut it. Quality counts here, so you should look for an organic coffee that’s rich in polyphenols and other potentially bioactive compounds.
Start Thinking About Colon Cancer Early
Overall, the number of new colon cancer cases is moving in a favorable direction. Unfortunately, among younger folks, it’s gaining more traction. Just like with other health issues such as dementia, prostate issues, and diabetes, it’s best to make healthy lifestyle changes early. This can help set the stage for healthier aging and reduce your risk of developing serious, chronic health issues as you get older.