title: Increasing the vegetable intake dose is associated with a rise in plasma carotenoids without modifying oxidative stress or inflammation in overweight or obese postmenopausal women.
abstract: The optimal amount of vegetable consumption required to reduce chronic disease risk is widely debated. Intervention trials evaluating biological activity of vegetables at various doses are limited. We conducted a 3-dose, crossover feeding trial to test the hypothesis that vegetable intake is associated in a dose-dependent manner with increased plasma carotenoids and subsequently reduced oxidative stress and inflammation in 49 overweight, postmenopausal women. Participants were assigned in random order to 2 (130 g), 5 (287 g), and 10 (614 g) daily servings of fresh, greenhouse-grown vegetables for 3-wk intervals with a 4-wk washout period between treatments. Plasma total carotenoids significantly increased from 1.63 to 2.07 μmol/L with a dose of 2 vegetable servings, from 1.49 to 2.84 μmol/L with a dose of 5 vegetable servings, and from 1.40 to 4.42 μmol/L with a dose of 10 vegetable servings (pre-post paired ttests, all P < 0.001). The change during each feeding period increased with each dose level (P < 0.001). Urine concentrations of 8-isoprostane F2α, hexanoyl lysine, and serum high sensitivity C-reactive protein were not affected by any administered vegetable dose. In this variable-dose vegetable study, a dose-response for plasma carotenoids was demonstrated without significant change in oxidative stress and inflammation in overweight, postmenopausal women.
authors.affiliation: Department of Nutritional Sciences, University of Arizona, Tucson, AZ, USA.
authors.forename: Tracy E
authors.initials: TE
authors.lastname: Crane
authors.forename: Chieri
authors.initials: C
authors.lastname: Kubota
authors.forename: Julie L
authors.initials: JL
authors.lastname: West
authors.forename: Mark A
authors.initials: MA
authors.lastname: Kroggel
authors.forename: Betsy C
authors.initials: BC
authors.lastname: Wertheim
authors.forename: Cynthia A
authors.initials: CA
authors.lastname: Thomson
mesh_terms: D000368:Aged; D001130:Arizona / Q000453:epidemiology; D015415:Biomarkers / Q000097:blood / Q000652:urine; D015992:Body Mass Index; D002097:C-Reactive Protein / Q000032:analysis; D002338:Carotenoids / Q000097:blood*; D002908:Chronic Disease / Q000453:epidemiology / Q000517:prevention & control; D018592:Cross-Over Studies; D015237:Dinoprost / Q000031:analogs & derivatives / Q000652:urine; D005260:Female; D006801:Humans; D008239:Lysine / Q000652:urine; D008875:Middle Aged; D009765:Obesity / Q000097:blood / Q000178:diet therapy / Q000276:immunology* / Q000652:urine; D050177:Overweight / Q000097:blood / Q000178:diet therapy / Q000276:immunology* / Q000652:urine; D018384:Oxidative Stress; D017698:Postmenopause; D012307:Risk Factors; D014675:Vegetables
chemical_list: D015415:Biomarkers; C120589:N(epsilon)-hexanoyllysine; C075750:8-epi-prostaglandin F2alpha; D002338:Carotenoids; D002097:C-Reactive Protein; D015237:Dinoprost; D008239:Lysine