Postprandial Effects of Pecans Ingestion on Plasma Level of Nutrients, Polyphenolic Compounds and Biomarkers of Antioxidant Status in Human Volunteers
Pecans (Carya illinoinensis) are rich sources of polyphenolic compounds and nutrients, which have antioxidant capacity results in favorable reductions in plasma lipids and lipoproteins. However, the health benefits of pecans may not be limited to blood lipid changes. There has been very little investigation into the contribution of bioactive components found in nuts to antioxidant protection. The purposes of the study were 1) to determine the impact of pecan consumption on concentration of total plasma polyphenols and their peak concentration over time. 2) to measure the effect of a pecan diet on postprandial levels of plasma lipid peroxidation and on plasma antioxidant capacity. Sixteen healthy subjects participated in our randomized 3x3 crossover study. A test meal of whole pecan, ground pecan or purified olive oil (control) was given to each subject immediately after a baseline blood draw. Blood specimens were collected thereafter at 1-, 2-, 3-, 5-, 8-, and 24-h. The study was split into 2 phases, with 8 subjects in each phase. Results were said to be significant at p =< 0.05. Total polyphenols reached the highest level at 5-h after the baseline draw for the pecan meal. The ORAC and FRAP assays each reached their highest level at 2-h (ground pecan, p = 0.001 and whole pecan, p = 0.002). TEARS decreased the greatest at 8-h (p = 0.013) and oxidized LDL at 3-h (p = 0.018). Our results indicate that antioxidants found in pecans may increase antioxidant capacity and ability, and therefore decrease oxidative stress. Regular consumption of pecans may contribute to a reduction in chronic and age-related diseases.
Biochemical Phenomena, Metabolism, and Nutrition, Lipids, Nutrition, Carya; Nuts -- chemistry; Plants, Edible; Nutritive Value; Postprandial Periods; Phenols -- therapeutic use; Antioxidants -- metabolism; Dietary Fats, Unsaturated -- therapeutic use; Lipid Peroxides; Oxidation-Reduction; Cardiovascular Diseases -- prevention & control; Neoplasms -- prevention & control; Prospective Studies.
Networked Digital Library of Theses and Dissertations