Impaired baroreflex sensitivity is connected to heart diseases and metabolic syndrome. The baroreflex is a mechanism to maintain blood pressure. If blood pressure is high, the baroreflex ensures that the heart frequency is reduced. As a result, the blood pressure drops. When blood pressure is low, the baroreflex is suppressed, which results in the heart frequency increasing and the blood pressure rising. In a study conducted in 2005, South African researchers studied whether the composition of diets influences the sensitivity of the baroreflex. They focussed particularly on walnuts, which are rich in polyunsaturated fatty acids, and cashew nuts, which contain several monounsaturated fatty acids. For the study they divided 62 subjects with metabolic syndrome into three groups. Patients with metabolic syndrome display several different risk factors for cardiovascular diseases, such as e.g. overweight, hypertension and/or elevated blood sugar and lipid values. One group was given food in which 20 % of energy came from walnuts. The second group was given food in which 20 % of energy came from unsalted cashew nuts and the third group (the control group) received average food. After eight weeks, only the subjects in the cashew nut group showed increased baroreflex sensitivity. The results of this study emphasise the advantageous characteristics of nuts with regard to heart health. It additionally shows that blood pressure can be influenced by eating habits.
Schutte AE et al.: Modulation of Baroreflex Sensitivity by Walnuts Versus Cashew Nuts in Subjects With Metabolic Syndrome. American Journal of Hypertension. 2006, doi:10.1016/j.amjhyper.2005.12.014