Walnuts may have the potential to positively affect several important health factors, according to a new review.

From their impact on colon cancer and certain aspects of cognitive aging, to their positive effect on both gut health and vascular health, the research findings presented at Experimental Biology 2015 (EB) detail the latest understanding of walnuts' inner workings.

"These findings help advance the understanding of the many advantages of eating walnuts as part of a healthy diet, and add to the more than 159 published papers over 20 years that have shown how walnuts affect heart health, diabetes, cancer, cognition, fertility and weight management," Dennis A. Balint, CEO of the California Walnut Commission, said in a statement.

For the first time, researchers looked at whether components of walnuts have an effect on colon cancer cells. This cell study1 was conducted by the Department of Nutritional Science and Food Management at the Ewha Womans University in Korea, and showed that walnut extract significantly slowed the survival of the cancer stem cells as well as reduced the stemness of colon cancer stem cells. Given the results, researchers state there is reason to further explore the role of walnut consumption in colon cancer therapies targeting cancer stem cells.

A recent animal study by the Department of Physiology School of Medicine at Louisiana State University Health Sciences Center found that walnuts improve gut health. The gut microbiome is an ecosystem of bacteria that helps our bodies digest and use the food we eat; changes in the gut microbiome are linked to chronic diseases. A diet with walnuts (approximately 2 ounce human diet equivalent) significantly altered the ratio of the two communities, therefore suggesting "a new mechanism, changing the gut microbial environment, by which walnuts may exert their beneficial health effects." As this study was performed on animals, however, findings cannot yet be implied for humans.

A third animal study from the Human Nutrition Research Center on Aging at Tufts University looked at healthy rats, both young and old, and the impact of walnuts - a source of polyunsaturated fatty acids and nutrients such as folate, selenium, magnesium and polyphenols - on mechanisms in critical regions of the brain. Animals were segmented into three groups - one, the control group, who ate no walnuts at all (0%); a second that had 6% of their diet comprised of walnuts; and a third that had 9% of their diet comprised of walnuts (equivalent to one ounce and 1.5 ounces respectively in a human diet). The groups were monitored for ten weeks.

Researchers said these findings pave the way for additional research aimed at understanding walnuts' role in disease prevention and management.