Mediterranean diet and cognitive function: a French study.
Study Goal
The researchers aimed to investigate the association between midlife Mediterranean diet adherence and cognitive performance later in life, and whether occupation and education modified this effect.
Results Summary
The study found no significant association between Mediterranean diet adherence and cognitive performance, except for minor effects on phonemic fluency and backward digit span scores. A weak association was observed in manual workers, but no interaction was found with educational level.
Population
3083 middle-aged subjects from the SU.VI.MAX study.
Effective Dosage
Not specified
Duration
Dietary records were collected from 1994-1996, with cognitive assessments in 2007-2009 (13-year follow-up).
Interactions
None mentioned
| Intervention | Direction | Endpoint | Population | Dosage | Impact | Claim # |
|---|---|---|---|---|---|---|
Mediterranean diet adherence | no change | cognitive scores | middle-aged subjects | - | no association | #1 |
Mediterranean-Style Dietary Pattern Score (MSDPS) | decrease | phonemic fluency score | middle-aged subjects | - | lower phonemic fluency score | #2 |
Mediterranean Diet Score (MDS) | decrease | backward digit span score | middle-aged subjects | - | lower backward digit span score | #3 |
Mediterranean diet adherence | decrease | composite cognitive score | manual workers | - | lower composite cognitive score | #4 |
Mediterranean diet adherence | no change | cognitive function | subjects irrespective of educational level | - | no beneficial effect | #5 |
BACKGROUND: Evidence on the association between Mediterranean diet (MedDiet) adherence and cognition is presently inconsistent. OBJECTIVES: The aims of this study were to investigate the association between midlife MedDiet adherence and cognitive performance assessed 13 y later among participants in the SU.VI.MAX (Supplementation with Vitamins and Mineral Antioxidants) study and to test the hypothesis of effect modification by occupation and education as cognitive reserve markers. DESIGN: A Mediterranean Diet Score (MDS) and a Mediterranean-Style Dietary Pattern Score (MSDPS) were estimated by using repeated 24-h dietary records (1994-1996) from 3083 middle-aged subjects. Cognitive performance was assessed in 2007-2009 by using 6 neuropsychological tests, and a composite score was built. Subgroup analyses were performed according to occupational and educational status. Mean differences and 95% CIs were estimated through covariance analyses. RESULTS: After potential confounders were accounted for, no association between MDS or MSDPS and cognitive scores was detected except for a lower phonemic fluency score with decreasing MSDPS (P = 0.048) and a lower backward digit span score with decreasing MDS (P = 0.03). In turn, a low MDS was related to a lower composite cognitive score in the small subsample of manual workers (n = 178, P-interaction = 0.04) who could be hypothesized to have low cognitive reserve. MedDiet adherence did not interact with educational level in relation to cognitive function. CONCLUSION: This study did not find support for a beneficial effect of MedDiet adherence on cognitive function, irrespective of educational level, which is the strongest indicator of cognitive reserve.