People with stage 3 colon cancer who consumed two ounces or more of tree nuts per week had a 42% lower chance of cancer recurrence and 57% lower chance of death than those who did not eat tree nuts.
The study did not find any lower risk of cancer recurrence for those who ate peanuts which are a legume and not a tree nut. Nuts are great sources of many micronutrients and both fermentable fiber (which feeds the gut microbiome) and non-fermentable fiber.
The benefit of eating nuts was consistent after adjusting the data for other factors that can influence cancer recurrence, including patient age, body mass index, gender, and genomic changes in the tumor. This study was not a clinical trial so it does not prove causation but it is an interesting finding that provides a framework for future studies.