Kay CD, Gebauer SK, West SG, Kris-Etherton PM. Pistachios increase serum antioxidants and lower serum oxidized-LDL in hypercholesterolemic adults. J Nutr 140, 1093-1098

Department of Nutritional Sciences, The Pennsylvania State University, University Park, PA 16802, USA.
Journal of Nutrition (Impact Factor: 3.88). 03/2010; 140(6):1093-8. DOI: 10.3945/jn.109.117366
Source: PubMed


Pistachios are high in lutein, beta-carotene, and gamma-tocopherol relative to other nuts; however, studies of the effects of pistachios on oxidative status are lacking. We conducted a randomized, crossover controlled-feeding study to evaluate 2 doses of pistachios on serum antioxidants and biomarkers of oxidative status in 28 hypercholesterolemic adults (LDL-cholesterol >or=2.86 mmol/L). Participants consumed 3 isoenergetic diets for 4 wk each after a 2-wk baseline Western diet. Experimental diets included a lower-fat control diet without pistachios (25% total fat) with 1 serving/d (i.e. 32-63 g/d; energy adjusted) of pistachios (1 PD; 10% energy from pistachios; 30% total fat) or with 2 servings/d (63-126 g/d; energy adjusted) of pistachios (2 PD; 20% energy from pistachios; 34% total fat). When participants consumed the pistachio-enriched diets, they had higher plasma lutein (P < 0.0001), alpha-carotene, and beta-carotene (P < 0.01) concentrations than after the baseline diet. After consuming the pistachio diets, participants had greater plasma lutein (P < 0.001) and gamma-tocopherol (P < 0.05; 2 PD only) relative to the lower-fat control diet. After the 2 PD diet period, participants also had lower serum oxidized-LDL concentrations than following the baseline diet period (P < 0.05). After both the 1 PD and 2 PD diet periods, they had lower serum oxidized-LDL concentrations than after the control diet period (P < 0.05). The change in oxidized-LDL from baseline correlated positively with the change in LDL-cholesterol across all treatments (r = 0.42; P < 0.005). After controlling for the change in serum LDL-cholesterol as a covariate, increases in serum lutein and gamma-tocopherol following the 2 PD period were still modestly associated with decreases in oxidized-LDL (r = -0.36, P = 0.06 and r = -0.35, P = 0.08, respectively). This suggests that a heart-healthy diet including pistachios contributes to the decrease in the serum oxidized-LDL concentration through cholesterol-lowering and may provide an added benefit as a result of the antioxidants the pistachios contain.

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    • "A number of studies have shown beneficial effects of pistachio consumption on cardiovascular disease (CVD) risk factors, such as lipids, endothelial function, inflammation, blood pressure and oxidative status (Gebauer et al., 2008; Kay et al., 2010; Sari et al., 2010; Zhang et al., 2010; West et al., 2012). Phytochemicals previously identified from pistachios include phytosterols, fatty acids, lutein and tocopherols (USDA 2007; Philips et al., 2005; Wu & Prior, 2005). "
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    • "Hence, pistachio supplementation may improve blood lipids in experimental hyperlipidemia, which may have beneficial applications in the prevention or treatment of obesity. Kay et al. [89] evaluated the effect of two doses of pistachios on the oxidative status of 28 hypercholesterolemic subjects. The results showed that pistachios contributed to the decrease in serum oxidized LDL concentration through a cholesterol-lowering effect. "
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