What distinct physiological situation does the term salt-sensitive specifically describe?

Blood pressure reacting strongly to consuming too much sodium.

Salt sensitivity is defined as a specific measurable physiological response within the cardiovascular system where the consumption of dietary sodium directly results in a significant increase in an individual's blood pressure. This is distinct from merely feeling bloated or retaining fluid, although fluid retention can accompany high sodium intake. Crucially, it describes the *manner* in which blood pressure responds to changes in sodium levels, rather than just the baseline presence of high blood pressure itself. For a salt-sensitive person, even amounts slightly above the general recommendation can disproportionately impact their vascular status, leading to measurable BP spikes shortly after intake.