Diets high in pectin do not significantly affect blood pressure, according to a controlled experiment published by the National Institutes of Health. In this experiment, rats fed a diet high in pectin showed no marked difference in blood pressure from those fed a regular diet.
Though pectin is unlikely to directly affect blood pressure, the fiber which is found in fruit pith and pulp is still healthy for the heart. Pectin absorbs cholesterol and blocks its absorption, according to ABC News. Citrus pectin can protect the heart from scarring by disabling a harmful protein known as galectin-3. Potassium found in oranges reduces blood pressure by offsetting dietary salt.