Abstract
The pathogenesis and basic mechanisms of hypertension are not understood. Hypertension is now considered to reflect abnormality in one or more of the biologic systems that regulate flow and resistance. Its complications result from high intra-arterial pressure, and drug treatment substantially lessens these complications. The death rate from hypertension has dropped strikingly. Although current knowledge is not sufficient to develop predictably successful prevention programs, there is growing interest in applying available information. Epidemiologic studies have identified obesity as a major risk factor for hypertension; they have also been interpreted as showing that high dietary sodium intake causes hypertension in industrialized societies. Evidence on the role of obesity seems firm and can provide the basis for prevention programs. The role of sodium intake requires further study.