How Selenium and Omega-3s May Be Inhibitors for Colorectal Cancer

Key Takeaways:

• Consuming a diet rich in omega-3 fatty acids could potentially decrease the risk of developing colorectal cancer by nearly 40 percent.
• Intake of supplements containing selenium may decrease the likelihood of recurrent polyps, signifying a nearly 40 percent risk reduction in polyp recurrence for those consuming the supplement.
• Our bodies derive selenium from the consumption of plants which have absorbed the nutrient from soil, or from consuming animals or fish who have included such plants in their diet.
• Participants with the highest quarter of omega-3 fatty acid consumption were 39 percent less likely to have colorectal cancer, however this correlation wasn’t observed among black participants for still unclear reasons.
• While both selenium and omega-3s show potential in prevention of colorectal cancer, it’s unclear whether the observed benefits are due to these nutrients alone or due to a combination with other factors.

Two recent investigations attempt to shed light on the particular influence that diet supplements may have on the prevention of colorectal cancer, and its potential reoccurrence.

The Potential of Omega-3

Scientists from the National Institute for Environmental Health Sciences in the U.S. conducted a study suggesting that consuming a diet rich in omega-3 fatty acids could decrease the chances of developing colorectal cancer by nearly 40 percent.

Selenium: A Surprise Ally?

Another study from Italian cancer specialists proposes that the intake of supplements containing selenium can similarly decrease the likelihood of recurrent polyps.

Both these critical investigations were showcased at a Houston conference on cancer prevention, which was backed by the American Association for Cancer Research.

Details of the Selenium Study

This study involved the participation of 411 individuals, aged between 25 and 75, who had one or more colorectal polyps removed. They were given either a placebo or a supplement detailed as an antioxidant blend, which had selenium combined with methionnine, alongside zinc, vitamin A, vitamin C, and vitamin E.

Regular checks were carried out one, three, and five years after beginning the selenium regimen with the help of a colonoscopy. The findings were striking; polyps made a reappearance in just 4.2 percent of those who took the supplement, as opposed to 7.2 percent of those taking the placebo.

What this research signifies is a nearly 40 percent risk reduction in polyp recurrence for those consuming the supplement.

The possibility of remaining polyp-free after 15 years was estimated at about 48 percent in those taking the supplement, as opposed to 30 percent in those who did not.

The Importance of Selenium

Our bodies derive selenium from the consumption of plants which have absorbed the nutrient from soil, or from consuming animals or fish who have included such plants in their diet.

An earlier study proposed that selenium could restrict cell proliferation in the colon and rectum, although it’s also worth noting that the selenium contribution remains debatable. It’s unclear whether the benefit was due to selenium only or in combination with the other ingredients of the supplement.

Omega-3 Study

In this study by U.S. scientists, 1,878 individuals were questioned about their dietary habits over the past year, half of whom had colorectal cancer. Among the white participants, those with the highest quarter of omega-3 fatty acid consumption were 39 percent less likely to have colorectal cancer than those in the lowest quarter. However, for reasons still unclear to authors, this association wasn’t observed among black participants.

Sangmi Kim, the lead author of the study, states, “Our finding unequivocally supports evidence from earlier experimental and clinical studies stating that long-chain omega-3 fatty acids curtail tumor growth.”

Kim suggests increasing omega-3 intake through diet or potentially through a supplement. Omega-3 fatty acids are commonly found in fish such as salmon, mackerel, and herring, and plant-based sources include flaxseed, soybeans, and walnuts.

While other research has implied that omega-3 fatty acids could act as anti-inflammatory mechanisms and facilitate the prevention of cancer, it must be pointed out that the participants in this research were asked about their diets post their diagnosis with colorectal cancer. Given this caveat, there might be inaccuracies in their recall.

In addition, it is possible that the benefit may not be solely due to omega-3s. Those who consumed more fish may have maintained a healthier diet in overall terms.

Additional Information

For more details on colorectal cancer, please visit the American Association for Cancer Research site here.