Over the years, the many health benefits of plant-rich diets have been re-emphasized in more ways than one. A new study out of South Korea is set to pile up on those benefits with claims that healthy plant-rich foods could lower the risk of colorectal cancer by nearly a quarter but, only for men.

Colorectal cancer is ranked the third most common kind of cancer and the fourth most common cause of cancer death in the world. In 2019, a staggering 1,369,005 people were estimated to be living with the disease in the United States alone with a death rate of 13.1 per 100,000 men and women per year. 

“Colorectal cancer is the third most common cancer worldwide and the risk of developing colorectal cancer over a lifetime is one in 23 for men and one in 25 for women,” says corresponding author Dr. Jihye Kim. 

According to the authors down at Kyung Hee University, American men who consumed high amounts of healthy plant-based foods had a 22% lower risk of developing colorectal cancer, compared to those who ate the lowest amounts of healthy plant-based foods. 

To reach this conclusion, data was collected and analyzed from about 80,000 men and 94,000 women in Hawaii and Los Angeles. The male participants averaged 60 years, while the female participants averaged 59 at the start of the study period. 30.2 percent of them were Japanese American, 28.5 percent of them were Latino, 13 percent were African American and 7 percent of them were Native Hawaiian. 

The participants revealed their usual diet content over the previous year and the authors and carriers of the research assessed whether their diets were high in plant-based foods, enough to be classified as healthy or unhealthy. Whole grains, vegetables, and legumes were considered as healthy and conversely, refined grains, fruit juices, and products with sugar were considered unhealthy plant-based foods.

The incidence of new colorectal cancer cases was calculated until 2017 using data obtained from cancer registries and took account of participants’ age, family history of the disease, BMI, smoking history, other proclivities as well as multivitamin intake, and daily energy intake. During the study period, 4,976 participants (2.9%) developed colorectal cancer.

The selective benefit to men was attributed to the higher risk of men developing colorectal cancer compared to women hence, men stand to benefit more. Another potential explanation was menopausal hormone therapy use in women. Its use is associated with a lower risk of colorectal cancer in postmenopausal women.

According to the study, the suppression of carcinogenesis (development of cancer) by healthy plant foods such as fruits, vegetables, and whole grains could be a result of their dietary fiber, polyphenols, and carotenoid content. These compounds are widely known for their antioxidant and anti-inflammatory actions in animal models.

The team also speculated that gut microbiota might be responsible as they reduce the production of short-chain fatty acids through microbial fermentation, which can help maintain the mucosal lining and suppress the risk of carcinogenesis.

Above all, researchers emphasize the intake of healthy plant-based meals like fruits and veggies to slash the risk of colorectal cancer among the male population.

The full findings of the study can be seen in the journal BMC Medicine.

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