An investigation carried out by the Harvard University, in collaboration with researchers from the Ciberobn of the Rovira i Virgili University, has revealed that the consumption of nuts does not negatively affect the triglycerides, neither body weight, nor blood pressure, according to the work published in ‘The American Journal of Clinical Nutrition’.
In this way, this study has chosen walnuts as one of the most beneficial nuts for lowering cholesterol and triglyceride levels in our body. Walnuts are rich in a-linolenic and linoleic fatty acids. Therefore, it has been hypothesized that this unique nutritional composition of fatty acids may be responsible for the decrease in cholesterol and triglyceride concentrations observed in other nutritional studies.
Walnuts lower LDL cholesterol levels
Despite the numerous studies that have linked walnuts to lowering cholesterol and triglycerides, there are controversies on the subject. It was in 2009 when a study managed to verify how diets supplemented with walnuts reduce LDL cholesterol levels compared to other types of diets.
However, given the discrepancies observed between studies and taking into account that since 2009 more than 10 new scientific articles have been published in this regard, researchers from the Ciberobn of the Rovira i Virgili University, in collaboration with Harvard University, considered updating the meta-analysis of the year 2009 with the aim of seeing the effects of diets that include walnuts on the lipid profile and of a type of protein that transports lipids to the blood, known as apolipoproteins.
Harvard University Study on the Role of Walnuts in Triglycerides
During the study, 26 investigations were conducted with a total of 1,059 participants. Thus, Harvard University researchers were able to conclude that, compared to control diets, diets supplemented with walnuts lower total cholesterol by 6.99 mg / dL, LDL cholesterol by 5.51mg / dL, and triglycerides by 4.69mg / dL. However, the consumption of walnuts does not appear to have an effect on body weight or blood pressure compared to control diets.
In the words of the researchers, this study provides strong evidence of the benefits of walnut consumption on lipid profile without negatively affecting body weight or blood pressure. Despite being a food with a high energy density, the consumption of nuts does not make us gain weight, and therefore, they are postulated as an ideal complement to include it in a healthy diet for cardiovascular prevention.
Although the mechanism of action by which walnuts can improve the lipid profile is not exactly known, everything indicates that their high content of plant sterols, α-linolenic and linoleic fatty acids, and polyphenols, may be responsible. These nutrients contain high antioxidant and anti-inflammatory properties and can also interfere with the absorption of cholesterol and triglycerides.
This study has been led by researcher Marta Guasch-Ferré, post-doctoral researcher at Harvard University and Rovira i Virgili University, and professor Salas-Salvadó, principal investigator at Ciberobn, and published in the prestigious journal The American Journal of Clinical Nutrition.