title: Cardio-metabolic and immunological impacts of extra virgin olive oil consumption in overweight and obese older adults: a randomized controlled trial.
abstract: BACKGROUND
  Both aging and obesity are related to dysregulated immune function, which may be responsible for increased risk of infection and also chronic non-infectious diseases. Dietary lipids have been shown to impact immune and inflammatory responses and cardio-metabolic risk factors. No information on the impact of olive oil on immune responses of overweight and obese older adults is available.
  
  
  OBJECTIVE
  We aimed to determine the effect of replacing oils used in a typical American diet with extra virgin olive oil for 3 months on immune responses and cardio-metabolic risk factors in overweight and obese older adults.
  
  
  METHODS
  This was a randomized, single-blinded and placebo-controlled trial in 41 overweight or obese participants (aged ≥ 65) who consumed a typical American diet. Participants in the control (CON, n = 21) group were provided with a mixture of corn, soybean oil and butter, and those in the olive oil (OO, n = 20) group, with extra virgin olive oil, to replace substitutable oils in their diet. At baseline and 3 months, we measured blood pressure, biochemical and immunological parameters using fasting blood, and delayed-type hypersensitivity (DTH) skin response.
  
  
  RESULTS
  Compared to the CON group, the OO group showed decreased systolic blood pressure (P < 0.05), a strong trend toward increased plasma HDL-C concentrations (P = 0.06), and increased anti-CD3/anti-CD28 -stimulated T cell proliferation (P < 0.05). No differences were found in T cell phenotype, cytokine production, and DTH response between the two groups.
  
  
  CONCLUSIONS
  Our results indicate that substitution of oils used in a typical American diet with extra virgin olive oil in overweight and obese older adults may have cardio-metabolic and immunological health benefits. This trial was registered at clinicaltrials.gov as NCT01903304.
authors.affiliation: Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University, 711 Washington Street, Boston, MA 02111 USA ; Department of Health and Clinical Sciences, University of Massachusetts, Lowell 3 Solomont Way, Suite 4, Lowell, MA 01854 USA.
authors.forename: Mitra
authors.initials: M
authors.lastname: Rozati
authors.affiliation: Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University, 711 Washington Street, Boston, MA 02111 USA.
authors.forename: Junaidah
authors.initials: J
authors.lastname: Barnett
authors.affiliation: Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University, 711 Washington Street, Boston, MA 02111 USA.
authors.forename: Dayong
authors.initials: D
authors.lastname: Wu
authors.affiliation: Department of Health and Clinical Sciences, University of Massachusetts, Lowell 3 Solomont Way, Suite 4, Lowell, MA 01854 USA.
authors.forename: Garry
authors.initials: G
authors.lastname: Handelman
authors.affiliation: Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University, 711 Washington Street, Boston, MA 02111 USA.
authors.forename: Edward
authors.initials: E
authors.lastname: Saltzman
authors.affiliation: Department of Health and Clinical Sciences, University of Massachusetts, Lowell 3 Solomont Way, Suite 4, Lowell, MA 01854 USA.
authors.forename: Thomas
authors.initials: T
authors.lastname: Wilson
authors.affiliation: Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University, 711 Washington Street, Boston, MA 02111 USA.
authors.forename: Lijun
authors.initials: L
authors.lastname: Li
authors.affiliation: Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University, 711 Washington Street, Boston, MA 02111 USA.
authors.forename: Junpeng
authors.initials: J
authors.lastname: Wang
authors.affiliation: Institute of Food Science and Technology and Nutrition (ICTAN), Scientific National Research Council (CSIC), Madrid, Spain.
authors.forename: Ascensión
authors.initials: A
authors.lastname: Marcos
authors.affiliation: Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University, 711 Washington Street, Boston, MA 02111 USA.
authors.forename: José M
authors.initials: JM
authors.lastname: Ordovás
authors.affiliation: Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University, 711 Washington Street, Boston, MA 02111 USA.
authors.forename: Yu-Chi
authors.initials: YC
authors.lastname: Lee
authors.affiliation: Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University, 711 Washington Street, Boston, MA 02111 USA.
authors.forename: Mohsen
authors.initials: M
authors.lastname: Meydani
authors.affiliation: Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University, 711 Washington Street, Boston, MA 02111 USA.
authors.forename: Simin Nikbin
authors.initials: SN
authors.lastname: Meydani
keywords: Aging; Cardio-metabolic; Immune response; Obesity; Olive oil