THEORY OF OBJECTS. ARTICLE 9. 7 META-COMPARTMENT: CEREBROSPINAL FLUID (CEF). CEREBROSPINAL FLUID AS A PROTECTIVE ENVIRONMENT OF THE BRAIN: PP/IT PROFILE AND RESTORATION OF METABOLOMIC DIVERSITY IN PEOPLE 55+

Cerebrospinal fluid (CSF) is a medium that bathes the brain and spinal cord, providing neuroprotection, removal of metabolic waste, and transport of signaling molecules. After the age of 55, the metabolomic diversity of CSF decreases dramatically: the number of detectable metabolites drops from ~470 to a critical threshold of less than 150, which is associated with neurodegenerative diseases, cognitive decline, neuroinflammation, and accelerated brain aging. However, standard clinical analyses of CSF assess only a narrow set of parameters and do not reflect metabolomic diversity. The article shows how the theory of subjectabols makes it possible to measure the metabolic depletion of cerebrospinal fluid, what diseases are associated with it, and how foods with a high PC/IT profile, including biogenic nutrition, restore metabolomic diversity. The PP/IT profile is a format for representing two independent indices: the density of objects (PP) and the toxicity index (IT). The notation 250/8 means 250 beneficial molecular species and 8 harmful ones per 100 g of product — this is not a fraction, but two independent numbers side by side, like a blood pressure of 120/80. The profile is tied to the vector of product parameters: variety, origin, method of production, condition, freshness, and storage conditions. A monitoring protocol and practical recommendations for people 55+ are proposed.