A diet rich in key vitamins and healthy fats may help older men and women to stay cognitively sharp, as well as reduce brain shrinkage associated with Alzheimer’s Disease.  Conversely, a “junk food” diet (characterized by high trans fat intake) predicts lower cognitive scores, as well as reduced total cerebral brain volume.  G.L. Bowman, from Oregon Health and Science University (or guide, USA), and colleagues completed a study that specifically measured a wide range of blood nutrient levels and correlated them to performance on mental acuity tests.  The researchers enrolled 104 people, average age 87 years, none of whom experienced special risk factors for memory or mental acuity. The team tested 30 different nutrient biomarkers in their blood, and 42 participants also had MRI scans to measure their brain volume. The most favorable cognitive outcomes and brain size measurements were associated with two dietary patterns – high levels of marine fatty acids, and high levels of vitamins B, C, D and E. In contrast, consistently worse cognitive performance was associated with a higher intake of the type of trans-fats found in baked and fried foods, margarine, fast food and other less-healthy dietary choices. The researchers conclude that:  "Distinct nutrient biomarker patterns detected in plasma are interwpretable and account for a significant degree of variance in both cognitive function and brain volume.”