title: Postprandial oxidative stress is increased after a phytonutrient-poor food but not after a kilojoule-matched phytonutrient-rich food.
abstract: Research indicates that energy-dense foods increase inflammation and oxidative activity, thereby contributing to the development of vascular disease. However, it is not clear whether the high kilojoule load alone, irrespective of the nutritional content of the ingested food, produces the postprandial oxidative and inflammatory activity. This study investigated the hypothesis that ingestion of a high-fat, high-sugar, phytonutrient-reduced food (ice cream) would increase oxidative and inflammatory activity greater than a kilojoule-equivalent meal of a phytonutrient-rich whole food (avocado). The individual contributions of the fat/protein and sugar components of the ice cream meal to postprandial inflammation and oxidative stress were also quantified. Using a randomized, crossover design, 11 healthy participants ingested 4 test meals: ice cream, avocado, the fat/protein component in ice cream, and the sugar equivalent component in ice cream. Plasma glucose, cholesterol, triglycerides, and inflammatory and oxidative stress markers were measured at baseline and 1, 2, and 4 hours (t1, t2, t4) after ingestion. Lipid peroxidation was increased at 2 hours after eating fat/protein (t0-t2, P < .05) and sugar (t1-t2, P < .05; t1-t4, P < .05). Antioxidant capacity was decreased at 4 hours after eating ice cream (t0-t4, P < .01) and sugar (t0-t4, P < .01). Ingestion of a kilojoule-equivalent avocado meal did not produce any changes in either inflammatory or oxidative stress markers. These data indicate that the ingestion of a phytonutrient-poor food and its individual fat/protein or sugar components increase plasma oxidative activity. This is not observed after ingestion of a kilojoule-equivalent phytonutrient-rich food.
authors.affiliation: School of Medical Sciences, Faculty of Medicine, University of New South Wales, NSW, Australia; Australasian Research Institute, Sydney Adventist Hospital, NSW, Australia.
authors.forename: Amanda
authors.initials: A
authors.lastname: Khor
authors.affiliation: School of Medical Sciences, Faculty of Medicine, University of New South Wales, NSW, Australia; Australasian Research Institute, Sydney Adventist Hospital, NSW, Australia; Sydney Medical School, University of Sydney, NSW, Australia. Electronic address: r.grant@unsw.edu.au.
authors.forename: Ross
authors.initials: R
authors.lastname: Grant
authors.affiliation: Australasian Research Institute, Sydney Adventist Hospital, NSW, Australia.
authors.forename: Chin
authors.initials: C
authors.lastname: Tung
authors.affiliation: School of Medical Sciences, Faculty of Medicine, University of New South Wales, NSW, Australia; Australasian Research Institute, Sydney Adventist Hospital, NSW, Australia.
authors.forename: Jade
authors.initials: J
authors.lastname: Guest
authors.affiliation: School of Medical Sciences, Faculty of Medicine, University of New South Wales, NSW, Australia; Australasian Research Institute, Sydney Adventist Hospital, NSW, Australia.
authors.forename: Belinda
authors.initials: B
authors.lastname: Pope
authors.affiliation: School of Medical Sciences, Faculty of Medicine, University of New South Wales, NSW, Australia.
authors.forename: Margaret
authors.initials: M
authors.lastname: Morris
authors.affiliation: Department of Statistics, Macquarie University, NSW, Australia.
authors.forename: Ayse
authors.initials: A
authors.lastname: Bilgin
mesh_terms: D000328:Adult; D000368:Aged; D000975:Antioxidants / Q000008:administration & dosage*; D004032:Diet; D002149:Energy Intake; D005260:Female; D005638:Fruit; D006801:Humans; D007054:Ice Cream; D015227:Lipid Peroxidation; D008297:Male; D062407:Meals; D008875:Middle Aged; D009753:Nutritive Value; D018384:Oxidative Stress; D027421:Persea; D064209:Phytochemicals / Q000008:administration & dosage*; D019518:Postprandial Period
chemical_list: D000975:Antioxidants; D064209:Phytochemicals
keywords: Fat; Human; Inflammation; Kilojoule; Oxidative stress; Postprandial; Sugar