Carol O'Neil of Louisiana State University and colleagues compared the health risk for cardiovascular disease, type 2 diabetes and metabolic syndrome of nut consumers with that of non-consumers.
The researchers said the study involved data from 13,292 U.S. adults age 19 and older who participated in the 1999 to 2004 National Health and Nutrition Examination Survey.
The data showed 18.6 percent of those ages 19–50 were nut consumers -- ate more than one-quarter of an ounce a day -- while 21 percent age 51 and older ate nuts regularly.
The study, published in the Journal of the American College of Nutrition, said tree nut consumption was associated with a decreased prevalence of selected risk factors for cardiovascular disease, type 2 diabetes and metabolic syndrome.
The nut eaters were also 5 percent less likely to have metabolic syndrome and also had a lower prevalence of four risk factors for metabolic syndrome: Abdominal obesity, high blood pressure, high fasting glucose levels and low high-density lipoprotein, the "bad," cholesterol. The nut eaters also had decreased BMI and waist circumference, the study said.
Tree nuts include: Almonds, Brazil nuts, cashews, hazelnuts, macadamia nuts, pecans, pine nuts, pistachios and walnuts.