A Year-long Trial to Examine the Effects of a Daily Dose of Walnuts on Cardiometabolic Risk Markers in an Elderly Population

Background/ObjectiveLong-term observational studies and short-term intervention trials have linked nut consumption with improved cardiometabolic risk factors. However, long-term trials on nut intake and cardiometabolic risk are lacking. We conducted a year-long trial to examine the effects of a daily dose of walnuts on cardiometabolic risk markers in an elderly population. MethodsA total of 356 participants (Ages 62–79) were randomly assigned to a walnut or control group. Participants in the walnut group were provided with packaged walnuts (1, 1.5, or 2 oz.) and asked to incorporate into their daily habitual diet. The walnut supplement provided an estimated 15% of their daily energy. Participants in the control group were asked to continue with their habitual diet and to refrain from eating walnuts or excessive intake of other nuts. Both groups were asked to maintain their lifestyles. Blood samples were obtained at baseline and one year and assayed for total cholesterol, LDL and HDL cholesterol, and trigl...