The data comes from more than analysis of 135,000 people in the USA over a ten year period. Led by Professor Frank Hu and his team at the Harvard School of Public Health, USA, the researchers investigated the possible association between walnut intake and the incidence of type 2 diabetes in 2 large cohort studies: the Nurses’ Health Study (NHS) and NHS II.
Writing in the Journal of Nutrition, the team show that eating walnuts two or three times a week was associated with a 24% reduction in the risk of developing type 2 diabetes.
"The findings from our study and others support the benefits of the incorporation of nuts, including walnuts, as a component of a healthy diet for diabetes prevention," wrote Hu and his colleagues.
"Frequent intake of walnuts was associated with a lower risk of incident type 2 diabetes in women, the association persisted after adjustment for other lifestyle factors, and it was partially mediated by BMI," said the authors- who added that further studies are now needed to confirm their results.
Hu and his colleagues tracked 137,893 female nurses, aged between 35 and 77 years, over a 10-year period to see how many developed type 2 diabetes - as part of the NHS and NHSII study. Dietary habits were closely monitored, including details on how often they ate nuts, particularly walnuts.
After allowing for body fat and weight, the researchers found eating walnuts one to three times a month was associated with a lower risk of developing type 2 diabetes by 4%, once a week by 13%, and at least twice a week by 24%
“These results suggest higher walnut consumption is associated with a significantly lower risk of type 2 diabetes in women," Hu and his colleagues concluded.