Quantifying salt sensitivity.

Inner surfaces of blood vessels and outer surfaces of erythrocytes are coated with a negatively charged protective film of proteoglycans, which serves as an effective buffer system for the positively charged sodium ions. If this protective coating is poorly developed or impaired, it loses its buffering capacity. As a consequence, the organism becomes increasingly sensitive to sodium, which in the long run leads to organ damage, especially if daily salt consumption is high. Recently, it has become possible to quantify salt sensitivity using a technically simple method - the salt blood test (SBT). Aim of this mini-review is to explain the physiological concept underlying the SBT and its potential practical relevance in the prevention of cardiovascular disease.