Handful of pistachios a day could help people with diabetes manage stress

New research suggests that eating pistachios can improve the health of people with diabetes by reducing the body’s response to stress.
The study, published in the Journal of the American Heart Associatio, found that two servings of pistachios per day “lowered vascular constriction during stress and improved neural control of the heart” in adults with type 2 diabetes.
The finding comes from a team of researchers at Penn State University, USA, who investigated the effects of pistachios on responses to standardised stress tasks in patients with well-controlled type 2 diabetes.
All participants were put on a typical American diet, which contained 36% fat and 12% saturated fats, for two weeks, and then randomly assigned to one of two test diets – a standard heart healthy diet (27% fat and 7% saturated fat) and a diet containing two daily servings of pistachio nuts (roughly 150 nuts per day). The latter diet was 33% fat and 7% saturated fat.
At the end of each four-week diet period, blood pressure was measured along with participants’ total peripheral vascular resistance at rest and during two stress tests.
Compared with the low fat, heart healthy diet, the pistachio diet lowered vascular constriction during the stress tests. In other words, blood vessels remained more relaxed and open during stress.
In addition to blunting the body’s vascular response to stress, the pistachio diet also had positive effects on blood pressure and heart rate variability – a measure of how well heart function is controlled by the nervous system.
The researchers explained that while laboratory measurements of blood pressure were not affected by pistachios, real-world measures of blood pressure (24-hour ambulatory blood pressure) were significantly lower following the pistachio diet. In particular, systolic blood pressure during sleep was reduced by an amount sufficient to lower workload on the heart.
“Although nuts are high in fat, they contain good fats, fibre, potassium and antioxidants,” lead author Sheila G. West said. “Given the high risk of heart disease in people with diabetes, nuts are an important component of a heart healthy diet in this population.
“If sustained with longer term treatment, these improvements in sleep blood pressure, vascular response to stress and vagal control of the heart could reduce risk of heart disease in this high risk [diabetic] group,” West concluded.