A study published earlier this month confirms what many of us already know: Colorectal cancer rates are rising dramatically among young people. In fact, colorectal cancer is the leading cause of cancer death in adults under 50 years old.
Though scientists are still rushing to pinpoint the exact cause of the uptick, many are confident that it has to do with the so-called "Western diet" that's common in the U.S.—one that is high in processed foods and low in fruits, vegetables, and fiber. This eating pattern can lead to inflammation throughout the body that can, in turn, increase one's risk of developing colon cancer.
However, a groundbreaking new study has found that eating a handful of this healthy snack food a day can reduce systemic inflammation while also lowering colon cancer risk.
Inflammation is related to colon cancer.
As Best Lifepreviously explained, a diet high in fat but low in fiber (such as the Western diet) can lead to intestinal dysbiosis, an imbalance of the good bacteria in one's gut.
A 2024 study published in the Journal of Clinical Oncology found that "an increased inflammation state characterizes dysbiosis and may promote an immunosuppressive tumor microenvironment and suppress antitumor immune surveillance."
A separate 2021 study published in the journal Gut analyzed 162 colon cancer tumor samples and found that they exhibited a "distinct pro-inflammatory bias."
RELATED: The 3 "Ultraprocessed" Foods You Must Avoid for a Longer Life, 30-Year Study Finds.
But snacking on walnuts could lower inflammation and colon cancer risk.
However, a new study published this month in the journal Cancer Prevention Research suggets that walnuts' high concentration of ellagitannins could improve systemic inflammation in the body while also reducing colon cancer risk.
"Ellagitannins in the walnut are importantly providing the anti-inflammatory and anti-cancer properties that we’re seeing in patients in our clinical trial research, particularly the gut’s conversion of ellagitannins to a potent anti-inflammatory agent, urolithin A," said Daniel W. Rosenberg, PhD, study author and a professor at the UConn School of Medicine, via a press release.
What exactly are ellagitannins? The press release defines them as "plant-derived polyphenol compounds found in walnuts...shown to be metabolized exclusively by the gut microbiome into a wide range of anti-inflammatory molecules called urolithins."
Urolithins are considered free radical scavengers, meaning they help curb oxidative stress on the body's cells, thereby reducing inflammation.
To arrive at these findings, the researchers enlisted 39 participants between the ages of 40 and 65 with an elevated risk for colon cancer. For three weeks, they consumed no other ellagitannin-rich foods other than walnuts. At the conclusion of the study period, they underwent high-definition colonoscopies, some of which resulted in the removal of colon polyps (small growths that can turn into cancer if left untreated). Researchers determined the following due to walnut consumption:
- Urine samples showed high levels of peptide YY, a protein that is "associated with inhibition of colorectal cancer"
- Blood samples showed several markers of reduced inflammation, especially in obese participants
- Polyp tissues had reduced amounts of proteins usually found in colon cancer
"There are many potential benefits one can get from eating walnuts, with so little downside risk, that just grabbing a handful every day is really something that you can easily do for your long-term health benefit," concluded Rosenberg.
RELATED: Doctor Reveals 4 Fruits That Can Lower Your Colon Cancer Risk.
Consider eating walnuts with yogurt.
Two other recent studies may persuade people to eat walnuts with yogurt or milk.
The first, published in the journal Gut Microbes, analyzed the dietary and health habits of more than 150,000 people over three decades, including 3,000 cancer cases. According to a press release, these researchers found that "yogurt consumption over time may protect against colorectal cancer through changes in the gut microbiome."
As Best Lifereported at the time, "Specifically, those who ate two or more servings of yogurt per week had a 20 percent lower rate of Bifidobacterium-positive proximal colon cancer, a type of colorectal cancer that occurs in the right side of the colon and has worse survival outcomes than other types of the disease. Of the cancer cases studied, about 30 percent had detectable Bifidobacterium in their tumor tissue."
Yogurt could also help reduce colon cancer risk due to its high vitamin C levels.
Another study published in Nature Communications consulted the health data of 542,778 women in the U.K., including 12,251 colon cancer cases over nearly 17 years. Their findings showed that consuming 300 mg per day of calcium—about one cup of 1 percent milk or half a cup of plain, nonfat or low-fat yogurt—can reduce colorectal cancer risk by 17 percent.
In speaking with Cancer Research UK, Keren Papier, MD, the first author of the study and a senior nutritional epidemiologist at the University of Oxford, said, "It’s suggested that calcium might protect against [colon] cancer by binding to bile acids and free fatty acids to form a type of a harmless 'soap,' which stops them from damaging the lining of our gut."
