A method of attenuating, treating or preventing cognitive aging in an individual who does not have dementia includes administering to the individual a therapeutically effective amount of a composition containing an omega-3 fatty acid, a nitric oxide releasing compound, Vitamin B12 and choline. The composition is administered in a daily dose that provides 0.1 to 50 times the recommended daily requirement (RDA) of Vitamin B12 per day, more preferably 0.1 to 40 times the recommended daily requirement (RDA) of Vitamin B12 per day and 0.01 to 10.0 times the recommended daily requirement (RDA) of choline. Optionally Vitamin B6 and/or Vitamin B9 can be included in the composition. The method can achieve a benefit that is one or more of decreasing brain atrophy, increasing or maintaining number of synapses, increasing amyloid-β phagocytosis, or decreasing or maintaining neuro inflammation in the non-demented individual. The method can prevent dementia in an individual at risk thereof, for example an elderly human.