Mediterranean diet improves cognition: the PREDIMED-NAVARRA randomised trial
- Elena H Martínez-Lapiscina1,2,
- Pedro Clavero3,
- Estefania Toledo1,4,
- Ramon Estruch4,5,
- Jordi Salas-Salvadó4,6,
- Beatriz San Julián1,
- Ana Sanchez-Tainta1,
- Emilio Ros4,7,
- Cinta Valls-Pedret4,7,
- Miguel Á Martinez-Gonzalez1
- 1Department of Preventive Medicine and Public Health, Medical School-Clinica, University of Navarra, Pamplona, Spain
- 2Center for Neuroimmunology, Institute of Biomedical Research August Pi Sunyer (IDIBAPS), Hospital Clinic of Barcelona, Barcelona, Spain
- 3Department of Neurology, Complejo Hospitalario de Navarra, Pamplona, Spain
- 4CIBER Fisiopatología de la Obesidad y Nutrición (CIBERobn), Instituto de Salud Carlos III (ISCIII), Madrid, Spain
- 5Department of Internal Medicine, Institute of Biomedical Research August Pi Sunyer (IDIBAPS), Hospital Clinic, University of Barcelona, Barcelona, Spain
- 6Human Nutrition Unit, IISPV, Universitat Rovira i Virgili, Reus, Spain
- 7Department of Endocrinology and Nutrition, Lipid Clinic, Institute of Biomedical Research August Pi Sunyer (IDIBAPS), Hospital Clinic of Barcelona, Barcelona, Spain
- Correspondence to Professor Miguel A Martinez-Gonzalez, Departamento de Medicina Preventiva y Salud Pública, Facultad de Medicina-Clínica, Universidad de Navarra, C/ Irunlarrea n1 1, Pamplona, Navarra E-31008, Spain;
- Received 17 December 2012
- Revised 8 March 2013
- Accepted 20 March 2013
- Published Online First 13 May 2013
Objective Previous observational studies reported beneficial effects of the Mediterranean diet (MedDiet) on cognitive function, but results were inconsistent. We assessed the effect on cognition of a nutritional intervention using MedDiets in comparison with a low-fat control diet.
Methods We assessed 522 participants at high vascular risk (44.6% men, age 74.6 ± 5.7 years at cognitive evaluation) enrolled in a multicentre, randomised, primary prevention trial (PREDIMED), after a nutritional intervention comparing two MedDiets (supplemented with either extra-virgin olive oil (EVOO) or mixed nuts) versus a low-fat control diet. Global cognitive performance was examined by Mini-Mental State Examination (MMSE) and Clock Drawing Test (CDT) after 6.5 years of nutritional intervention. Researchers who assessed the outcome were blinded to group assignment. We used general linear models to control for potential confounding.
Results 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, participants allocated to the MedDiet+EVOO showed higher mean MMSE and CDT scores with significant differences versus control (adjusted differences: +0.62 95% CI +0.18 to +1.05, p=0.005 for MMSE, and +0.51 95% CI +0.20 to +0.82, p=0.001 for CDT). The adjusted means of MMSE and CDT scores were also higher for participants allocated to the MedDiet+Nuts versus control (adjusted differences: +0.57 (95% CI +0.11 to +1.03), p=0.015 for MMSE and +0.33 (95% CI +0.003 to +0.67), p=0.048 for CDT). These results did not differ after controlling for incident depression.
Conclusions An intervention with MedDiets enhanced with either EVOO or nuts appears to improve cognition compared with a low-fat diet.