Since 1970, children and adolescents with hypertension have been detected with increasing frequency. Many of them were thought to have primary or essential hypertension and it remained unclear how they should be managed. Additionally, since tracking of blood pressure occurred even in early life, it was believed that youngsters with blood pressures persistently in the upper deciles for age were at increased risk for later hypertension. No clinical trials had been performed in this age group to examine the effects of non-pharmacologic or drug therapy in lowering blood pressure. The trial was one of the first attempts to examine the effects of a nutritional intervention on the rate of rise of blood pressure in late childhood and early adolescence.