Chronology of the sodium hypothesis and hypertension.

The observations that have provided the foundation of the sodium hypothesis of human hypertension are reviewed. Clinical observations made over 125 years ago initiated an investigative effort that has encompassed epidemiologic data, development of salt-related experimental models, and elucidation of theoretical mechanisms that interface Na+ balance with abnormal regulation of peripheral vascular resistance. In spite of the data available, a consensus is lacking on the relevance of applying the link between sodium intake and increased blood pressure in certain hypertensive patients to all persons.