LDL (Low Density Lipoprotein) particles are part of the lipoproteins that serve as important transport agents for water-insoluble (lipophilic) substances that do not dissolve in the blood plasma, such as cholesterol, fatty acids and phospholipids as well as lipophilic vitamins such as Vitamin E and Vitamin A. Oxidised LDL is generated by environmental poisons, free radicals and hazardous substances. When LDL penetrates into body cells, it creates foam cells that clog the arteries in conjunction with cholesterol. Oxidised LDL is therefore an important factor in the development and progression of arteriosclerosis. It is important to provide the human body with a sufficient amount of anti-oxidants to counteract this process. Pistachios contain more anti-oxidants such as lutein, Vitamin A and E, selenium, flavonoids and proanthocyanidins than other nuts.
A study by Kay et al. (2010) investigated the dose-dependent effects of pistachios on the anti-oxidative state in the blood serum and the concentration of oxidised LDL in 28 test persons with cardiovascular diseases. All trial participants were put on a three-step diet after they had eaten a normal Western diet for two weeks. At the beginning of the trial, the starting conditions were therefore equivalent for all trial participants. For periods of four weeks each, the trial participants received a control diet without pistachios, consumed 32-63 g of pistachios per day (10% of their total energy supply) or consumed 63-126 g pistachios per day (20% of their total energy supply).
The results of the study showed that the participants had a higher anti-oxidative blood status after eating the pistachio-rich diet than after eating the control diet. It was also noted that the concentration of oxidised LDL in the blood serum of the trial participants was significantly lower after the 3rd diet step (63-126 g pistachios per day) than at the start of the study. The increase in the anti-oxidative parameters such as lutein and Vitamin E therefore correlated with a reduction in oxidised LDL. The results of the study therefore confirm that a healthy diet that includes the consumption of pistachios makes a positive contribution to lowering the oxidised LDL in persons with hypercholesterolemia. The prophylactic properties of the pistachios are based on their high content of anti-oxidants.
Kay Colin D., Gebauer Sarah K., West Sheila G., Kris-Etherton Penny M. (2010): Pistachios Increase Serum Antioxidants and Lower Serum Oxidized-LDL in Hypercholesterolemic Adults. The Journal of Nutrition, S. 1093-1098.