The results highlight the importance of emphasising dietary and life-style factors in colon cancer survivorship.
People with colon cancer who regularly eat almonds, walnuts, hazelnuts and cashews are at significantly lower risk of cancer recurrence and mortality than those who do not, a study claims.
Researchers at Yale University Cancer Center in the US followed 826 participants in a clinical trial for a median of 6.5 years after they were treated with surgery and chemotherapy.
Those who regularly consumed at least two, one-ounce servings of nuts each week demonstrated a 42 per cent improvement in disease-free survival and a 57 per cent improvement in overall survival.
"Further analysis of this cohort revealed that disease-free survival increased by 46 per cent among the subgroup of nut consumers who ate tree nuts rather than peanuts," said Charles S Fuchs, director of Yale Cancer Center.
Tree nuts include almonds, walnuts, hazelnuts, cashews, and pecans, among others. In contrast, peanuts are actually in the legumes family of foods.
"These findings are in keeping with several other observational studies that indicate that a slew of healthy behaviours, including increased physical activity, keeping a healthy weight, and lower intake of sugar and sweetened beverages, improve colon cancer outcomes," said Temidayo Fadelu, a postdoctoral fellow at Dana-Farber Cancer Institute.
"The results highlight the importance of emphasising dietary and life-style factors in colon cancer survivorship," said Fadelu, lead author of the study published in the Journal of Clinical Oncology.
Many previous studies have reported that nuts, among other health benefits, may help to reduce insulin resistance, a condition in which the body has difficulty processing the insulin hormone.
Insulin resistance leads to unhealthy levels of sugar in the blood and is often a predecessor to type 2 diabetes and related illnesses.
Earlier research among patients with colon cancer has revealed worse outcomes among those with lifestyle factors that heighten insulin resistance, such as obesity, lack of exercise, and a diet with high levels of carbohydrates that quickly raise levels of blood sugar.
"These studies support the hypothesis that behaviors that make you less insulin resistant, including eating nuts, seem to improve outcomes in colon cancer," Fuchs said.
"However, we do not know yet what exactly about nuts is beneficial," he said.
Nuts also might play a positive role by satisfying hunger with less intake of carbohydrates or other foods associated with poor outcomes, Fuchs noted.