The journal of nutrition, health & aging

, Volume 17, Issue 6, pp 544–552

Virgin olive oil supplementation and long-term cognition: the Predimed-Navarra randomized, trial

  • Elena H. Martinez-Lapiscina
  • P. Clavero
  • E. Toledo
  • B. San Julian
  • A. Sanchez-Tainta
  • D. Corella
  • R. M. Lamuela-Raventos
  • J. A. Martinez
  • M. Á. Martinez-Gonzalez
Article

Abstract

Objective

XXXto assess the effect on cognition of a controlled intervention testing Mediterranean diets (MedDiet).

Design

XXXrandomized trial after 6.5 years of nutritional intervention.

Setting

Eight primary care centers affiliated to the University of Navarra.

Participants

A random subsample of 285 participants (95 randomly allocated to each of 3 groups) of the PREDIMED-NAVARRA trial. All of them were at high vascular risk (44.8% men, 74.1± 5.7 years at cognitive evaluation).

Interventions

Nutritional intervention comparing two MedDiets (supplemented with extra-virgin olive oil [EVOO] or mixed nuts) versus a low-fat control diet. Participants received intensive education to increase adherence to the intended intervention. Participants allocated to the MedDiet groups received EVOO (1 l/week) or 30 g/day of mixed nuts. Dietary habits were evaluated using a validated 137-item food frequency questionnaire (FFQ). Additionally, adherence to MedDiet was appraised using a 14-item questionnaire both at baseline and yearly thereafter.

Measurements

XXXcognitive performance as a main outcome and cognitive status (normal, mild cognitive impairment [MCI] or dementia) as a secondary outcome were evaluated by two neurologists blinded to group assignment after 6.5 years of nutritional intervention.

Results

Better post-trial cognitive performance versus control in all cognitive domains and significantly better performance across fluency and memory tasks were observed for participants allocated to the MedDiet+EVOO group. After adjustment for sex, age, education, apolipoprotein E genotype, family history of cognitive impairment/dementia, smoking, physical activity, body mass index, hypertension, dyslipidaemia, diabetes, alcohol and total energy intake, this group also showed lower MCI (OR=0.34 95% CI: 0.12–0.97) compared with control group. Participants assigned to MedDiet+Nuts group did not differ from controls.

Conclusion

A long-term intervention with an EVOO-rich MedDiet resulted in a better cognitive function in comparison with a control diet. However, non-significant differences were found for most cognitive domains. Participants allocated to an EVOO-rich MedDiet had less MCI than controls.

Key words

Mediterranean diet olive oil randomized controlled trial cognition mild cognitive impairment 

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Copyright information

© Serdi and Springer-Verlag France 2013

Authors and Affiliations

  • Elena H. Martinez-Lapiscina
    • 1
    • 2
    • 8
  • P. Clavero
    • 3
  • E. Toledo
    • 1
    • 4
  • B. San Julian
    • 1
  • A. Sanchez-Tainta
    • 1
  • D. Corella
    • 4
    • 5
  • R. M. Lamuela-Raventos
    • 4
    • 6
  • J. A. Martinez
    • 4
    • 7
  • M. Á. Martinez-Gonzalez
    • 1
    • 4
  1. 1.Department of Preventive Medicine and Public Health, Medical School-ClinicaUniversity of NavarraPamplonaSpain
  2. 2.Center for Neuroimmunology, Institute of Biomedical Research August Pi Sunyer (IDIBAPS)Hospital Clinic of BarcelonaBarcelonaSpain
  3. 3.Department of NeurologyComplejo Hospitalario de NavarraPamplonaSpain
  4. 4.CIBER Fisiopatología de la Obesidad y Nutrición (CIBERobn)Instituto de Salud Carlos III (ISCIII)MadridSpain
  5. 5.Department of Preventive MedicineUniversity of ValenciaValenciaSpain
  6. 6.Nutrition and Food Science Department, XaRTA, INSA. Pharmacy SchoolUniversity of BarcelonaBarcelonaSpain
  7. 7.Department of NutritionUniversity of NavarraNavarraSpain
  8. 8.Departamento de Medicina Preventiva y Salud Pública, Facultad de Medicina-Clínica Universidad de NavarraUniversidad de NavarraPamplona, NavarraSpain

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