graph TD

subgraph Body Water Input
A[Oral Intake (Fluids, Beverages)] --> E(Total Body Water);
B[Food Intake (Water Content)] --> E;
C[Metabolic Water (Oxidation of Nutrients)] --> E;
end

subgraph Total Body Water
E -- Distribution --> F{Intracellular Fluid (ICF)};
E -- Distribution --> G{Extracellular Fluid (ECF)};
G -- Subcompartments --> H[Interstitial Fluid];
G -- Subcompartments --> I[Plasma (Blood Water)];
G -- Subcompartments --> J[Transcellular Fluid (e.g., CSF, Synovial Fluid)];
end

subgraph Body Water Output
E --> K[Urinary System];
K -- Urine Excretion --> L(Water Loss);
E --> M[Respiratory System];
M -- Water Vapor (Exhalation) --> L;
E --> N[Integumentary System];
N -- Sweat --> L;
N -- Insensible Perspiration --> L;
E --> O[Gastrointestinal System];
O -- Feces (Water Content) --> L;
end

style Body Water Input fill:#ccf,stroke:#333,stroke-width:2px
style Total Body Water fill:#9cf,stroke:#333,stroke-width:2px
style Body Water Output fill:#fcc,stroke:#333,stroke-width:2px
style L fill:#f9f,stroke:#333,stroke-width:2px