Taste responses to saltiness among hypertensive subjects under different therapeutic regimens

Dietary sodium restriction is increasingly regarded as important in the prevention and treatment of essential hypertension. However, low-sodium diets are frequently considered unpalatable and therefore unfeasible. The objectives of this study were to determine (a) whether hypertensives, treated and untreated, differ in saltiness taste perception from age-matched normotensive controls and (b) whether sodium reduction can be accomplished by substituting another taste stimulus without reducing apparent saltiness and palatability. Subjects included 72 hypertensives, 44 to 69 years old, divided among three treatment groups; 25 age-matched normotensive controls; and an additional 21 normotensives, 20 to 43 years old, to provide an age continuum for evaluating age effects. Taste responses were measured in terms of saltiness intensity and preference using tomato juice varying systematically in sodium chloride and citric acid content. No significant differences were found between normotensives and hypertensives. No significant effects were associated with blood pressure status, therapeutic regimen, age, sex, race, or anthropometric measurements. Both sodium chloride and citric acid were main effects for saltiness, allowing a trade-off between salt and acid. Addition of citric acid permitted 50% reduction of sodium content in tomato juice without disturbing palatability criteria. Results provide a model for modifying other processed foods.