Health Effects of a Pecan [Carya illinoinensis (Wangenh.) K. Koch] Nut-rich Diet

This chapter outlines the contribution of pecans to human nutrition and reviews epidemiological and clinical research on pecan consumption and health. The epidemiological evidence is strong for the cardioprotective effect of nut consumption. When incorporated into meals, pecans reduce cardiovascular disease through a reduction in lipid and lipoprotein risk factors. Pecan extracts show high antioxidant capacity when tested by various assays in vitro. Pecan cultivars exhibit a high degree of variability in chemical composition and polyphenolic content due to genetic species and growth conditions. Total antioxidant capacity (sum of hydrophilic and lipophilic oxygen radical absorbance capacity of pecans at 179 micromols of Trolox equivalents) is the highest among the nuts. These data demonstrate that pecans are a rich source of redox-active compounds and may contribute to antioxidant protection provided in the diet by plant foods. There is a paucity of clinical intervention trials examining the effect of pecan consumption on in vivo oxidative stress biomarkers. Despite clear evidence of a link between nut consumption and heart disease, little is known about the mechanisms that mediate this effect. Preliminary research suggests that pecans may lower lipid oxidation and enhance antioxidant capacity.