A person prepares a sweet potato for a meal.Share on Pinterest
  • A new study finds that especially for men, a healthy plant-based diet may significantly reduce their risk for colorectal cancer.
  • The study found that the same trend was not seen in women, although they said women may have had a healthier diet at baseline.
  • Experts say eating a healthy well-rounded diet can be beneficial for many reasons.

A plant-based diet could have a significant impact on preventing colorectal cancer. Those are the findings from a study published in BMC Medicine that was conducted by a team of researchers from the United States and South Korea.

The study published this week involved 173,427 participants who were from a variety of ethnic groups. Results, which came after an average follow-up time of just over 19 years, found that men who followed a healthy plant-based diet had lower rates of colorectal cancer.

Women included in the study did not see the same benefit.

In total, 4,976 participants were found to have colorectal cancer. Further analysis split participants into a number of subgroups, including those who smoked and who consumed alcohol, as well as by race and ethnicity to identify any additional patterns.

Main Findings

  • The team found that men who ate the most healthy plant-based foods had a 22% decreased risk of developing colorectal cancer.
  • The difference between health benefits for men was higher in Japanese-American, Native Hawaiian and white populations as opposed to those who were identified as African American and Latino
  • Poor diets increased the risk of cancer that was found in the rectum rather than either side of the colon

The researchers used a set of data tools that allowed them to assess the quality of plant-based foods as well as animal products.

Mona S. Jhaveri, PhD., founder and director of Music Beats Cancer, says that the study had some limitations, but that it has significant value for looking at ways to prevent cancer.

“I think, in this study, what excites me the most is that it’s actually a method of [prevention,]” Jhaveri said. “And what I see in my world, in the biotech world. Is: we focus a lot on cures and treatments. And what the public really, in my opinion seeks are ways to prevent cancer or screen for it.”

Assistant clinical professor of in the department of nutrition and exercise physiology at Washington State University, Lisa Heneghen (MPH, RDN, CSO, CNSC), told Healthline that being able to assess the quality of plant-based foods was key as not all plant-based diets are healthy.

“We can say, ‘Eat this type of dietary pattern,’ but the way people interpret it or implement it can mean a lot of different things,” Heneghen said. Consuming “the more whole version of that plant food and the more pure version of that plant foods, so not processed, actually showed a reduced risk of colorectal cancer incidents, which is pretty interesting.”

The study found that women did not see the same benefits as men. The researchers theorized that women had a healthier diet than men in general. They suggest that, because women consumed a healthier diet from a baseline level, the changes for those who eat more healthy foods would be less drastic than in men.

The study contains a number of limitations identified by the researchers, including the possible need for further inquiry when it comes to the impact of dairy and fish consumption on colorectal cancer risks.

Jhaveri said that getting the public to significantly change their diet is an uphill battle as food companies spend millions every year on marketing less healthy food items.

“We’ve known these things forever,” Jhaveri said. “But yet, to put that into public practice is extremely hard because I think people who are disease experts are up against a lot of marketing… it becomes a really difficult thing to institute, and we need better ways to do it.

Heneghen, whose previous roles included work in cancer centers, says that few centers employ dietitians that could help people understand their cancer risk as related to their diet.

“It’s hard for cancer centers to really eat the cost of employing dietitians when there’s not a huge return in billing [from insurance companies,] and so that’s one big barrier,” Heneghen said. “They start charging patients for their time seeing a dietician, and then that’s a huge financial barrier and patients don’t want to pay out of pocket to visit with a dietitian.”