From http://www.sciencedaily.com/releases/2009/11/
091124093543.htm

ScienceDaily (Nov. 30, 2009) — Universitat Autònoma de Barcelona (UAB) researchers have confirmed that a diet rich in polyphenols and polyunsaturated fatty acids, patented as an LMN diet, helps boost the production of the brain's stem cells -neurogenesis- and strengthens their differentiation in different types of neuron cells.

The research revealed that mice fed an LMN diet, when compared to those fed a control diet, have more cell proliferation in the two areas of the brain where neurogenesis is produced, the olfactory bulb and the hippocampus, both of which are greatly damaged in patients with Alzheimer's disease. These results give support to the hypothesis that a diet made up of foods rich in these antioxidant substances could delay the onset of this disease or even slow down its evolution.
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Polyphenols can be found in tea, beer, grapes, wine, olive oil, cocoa, nuts and other fruits and vegetables. Polyunsaturated fatty acids can be found in blue fish and vegetables such as corn, soya beans, sunflowers and pumpkins. The LMN cream used in this study was composed of a mixture of natural products: dried fruits and nuts, coconut, vegetable oils rich in polyunsaturated fat and flour rich in soluble fiber.