Cer(d18:1/18:0) belongs to the ceramide family of sphingolipids, defined by an 18-carbon sphingoid backbone (d18:1) linked to an 18-carbon saturated fatty acid (18:0). Ceramides are structural components of cell membranes and also act as signaling molecules that influence membrane organization, vesicle trafficking, and the activity of metabolic pathways. Historically, ceramides were characterized as membrane lipids and later recognized as regulators of cell fate, inflammation, insulin signaling, and programmed cell death. Biochemically, they sit at the intersection of sphingolipid metabolism and lipid homeostasis — produced via de novo synthesis, salvage pathways, or sphingomyelin breakdown — and their concentrations reflect shifts in lipid handling and cellular stress responses.

Elevated Cer(d18:1/18:0) levels are associated with patterns of altered lipid metabolism, cellular stress signaling, and pro-inflammatory activity; in population studies, higher levels often track with markers of metabolic strain and increased vascular risk profiles. Low levels may reflect lower activity of ceramide-generating pathways or shifts in lipid composition, but very low values are less commonly the primary clinical focus and can be affected by genetics, diet, or lab variability. Interpretation should rely on the full Cardio Zoomer profile: ceramide values gain meaning when combined with lipoprotein particle data, inflammatory markers, metabolic measures, and clinical context rather than as a standalone indicator.

Cer(d18:1/18:0) is included in Cardio Zoomer to capture a specific axis of lipid signaling tied to plaque biology, metabolic stress, and inflammation. It complements particle and metabolic panels to clarify whether lipid-driven signaling contributes to a person’s cardiometabolic pattern, supporting more precise, data-driven discussion between provider and patient.