The present invention describes methods and compositions for the treatment of neurodegenerative conditions including Alzheimer's disease (AD) and aging. The present invention discloses an anaplerotic diet therapy for the treatment of AD. The high fat, low carbohydrate diet described in the various embodiments of the present invention increasing circulating ketone bodies, reduces amyloid-β (Aβ) deposition in AD patients, thereby improving cognition and locomotive skills.