Navigation Links
Pistachios may lower vascular response to stress in type 2 diabetes

Among people with type 2 diabetes, eating pistachios may reduce the body's response to the stresses of everyday life, according to Penn State researchers.

"In adults with diabetes, two servings of pistachios per day lowered vascular constriction during stress and improved neural control of the heart," said Sheila G. West, professor of biobehavioral health and nutritional sciences. "Although nuts are high in fat, they contain good fats, fiber, potassium and antioxidants. Given the high risk of heart disease in people with diabetes, nuts are an important component of a heart healthy diet in this population."

West and her colleagues investigated the effects of pistachios on responses to standardized stress tasks in patients with well-controlled Type 2 diabetes who were otherwise healthy. They used a randomized, crossover study design in which all meals were provided. Each of the diets contained the same number of calories.

After two weeks on the typical American diet -- containing 36 percent fat and 12 percent saturated fats -- participants were randomized to one of two test diets. During the four-week test diets, participants ate only food supplied by the study. The researchers reported the results of this study in a recent issue of the Journal of the American Heart Association.

Test diets included a standard heart-healthy diet -- 27 percent fat and 7 percent saturated fat -- and a diet containing two servings per day of pistachios -- about 3 ounces or 20 percent of calories from pistachio nuts. The typical research participant consumed about 150 pistachio nuts per day. The pistachio diet contained 33 percent fat and 7 percent saturated fat. Half of the nuts consumed each day were salted and half were unsalted. At the end of each four-week diet period, the researchers measured blood pressure and total peripheral vascular resistance at rest and during two stress tests -- a cold water challenge and a confusing mental arithmetic test.

"After the pistachio diet, blood vessels remained more relaxed and open during the stress tests," West said.

Although laboratory measurements of blood pressure were not affected by pistachios, real-world measures of blood pressure (measured by an automated monitor) were significantly lower after the pistachio diet. Katherine A. Sauder, former graduate student in biobehavioral health, conducted these measurements.

"We found that systolic blood pressure during sleep was particularly affected by pistachios," she said. "Average sleep blood pressure was reduced by about 4 points and this would be expected to lower workload on the heart."

The researchers found that the pistachio diet lowered vascular constriction during stress. When arteries are dilated, the load on the heart is reduced. The physical challenge involved immersing one hand into icy water for two minutes.

"This cold stressor produces a large vascular constriction response in most people," said West. "In comparison with a low fat diet, the pistachio diet blunted that vascular response to stress."

The same pattern was seen when participants engaged in a challenging and confusing mental arithmetic task.

"Our participants still felt frustrated and angry during the math test," West noted. "The pistachio diet reduced their bodies' responses to stress, but nuts are not a cure for the emotional distress that we feel in our daily lives."

Sauder added: "As in our last study of pistachios, we did not see lower blood pressure in the laboratory setting with this dose of nuts. However, we were surprised and pleased to see that 24-hour ambulatory blood pressure was lower after the pistachio diet."

The researchers also recorded improvements in heart rate variability, a measure of how well the nervous system controls heart function. These data indicate that pistachios increased the activity of the vagus nerve, an important part of the parasympathetic nervous system that can be damaged with diabetes.

"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 group," West said.


Contact: A'ndrea Elyse Messer
Penn State

Related biology news :

1. Eating lean beef daily can help lower blood pressure
2. For bees and flowers, tongue size matters
3. Babies born in Canada to immigrant mothers have lower risk of cerebral palsy: Study
4. Flower development in 3D: Timing is the key
5. Anti-androgen therapy for triple-negative breast cancer may benefit lower-androgen tumors
6. Vitamin D can lower weight, blood sugar via the brain
7. Air pollution controls linked to lower death rates in North Carolina
8. Potential cholesterol lowering drug has breast cancer fighting capabilities
9. Lower asthma risk is associated with microbes in infants homes
10. Notifying speeding mariners lowers ship speeds in areas with North Atlantic right whales
11. Growing camelina and safflower in the Pacific Northwest
Post Your Comments:
(Date:11/20/2015)... , November 20, 2015 ... company focused on the growing mobile commerce market and ... Gino Pereira , was recently interviewed on ... will air on this weekend on Bloomberg Europe ... America . --> NXTD ) ("NXT-ID" or ...
(Date:11/17/2015)... 17, 2015 Paris from ... --> Paris from 17 th until ... biometrics innovation leader, has invented the first combined scanner in ... same scanning surface. Until now two different scanners were required: ... can capture both on the same surface. This innovation ...
(Date:11/12/2015)... Nov. 12, 2015  A golden retriever that stayed ... dystrophy (DMD) has provided a new lead for treating ... the Broad Institute of MIT and Harvard and the ... . Cell, pinpoints a protective ... the disease,s effects. The Boston Children,s lab of ...
Breaking Biology News(10 mins):
(Date:12/1/2015)... Dr. Harry Lander , President of Regen, ... Chief Science Officer and recruits five distinguished scientists ... , President of Regen, expands his role to include ... five distinguished scientists to join advisory team --> ... to include serving as Chief Science Officer ...
(Date:11/30/2015)... ... ... Global Stem Cells Group announced that its scientific team is in the ... cells. The announcement starts a new phase toward launching the simple, quick system for ... lipoaspirate obtained from liposuction of excess adipose tissue. , Lipoaspirate, contains a large ...
(Date:11/30/2015)... Partnership includes an MPP licen ... niversity , s Solid Drug Nanoparticle (SDN) Technology ... up through cost cuts of priority ... licensees based anywhere in the world will have the right to make, use and ... , where licensees based anywhere in the world will have the right to make, ...
(Date:11/30/2015)... , ... November 30, 2015 , ... ... globally touring exhibition Jurassic World: The Exhibition, opening in March 2016 at Melbourne ... on a worldwide tour including several North American tour dates. The Exhibition is ...
Breaking Biology Technology: