There is no evidence to examine how dietary calcium affects the relationship between sodium and blood pressure. More research is needed in this area.

• Grade I means there is Good/Strong evidence supporting the statement;
• Grade II is Fair;
• Grade III is Limited/Weak;
• Grade IV is Expert Opinion Only;
• Grade V is Not Assignable.
• High (A) means we are very confident that the true effect lies close to that of the estimate of the effect;
• Moderate (B) means we are moderately confident in the effect estimate;
• Low (C) means our confidence in the effect estimate is limited;
• Very Low (D) means we have very little confidence in the effect estimate.
• Ungraded means a grade is not assignable.

One meta analysis (nine RCTs and one non-randomized control trial, N=966) assessing the effect of sodium or salt on blood pressure (BP), found an increase in sodium or salt intake resulted in an increase in systolic blood pressure (SBP) and diastolic blood pressure. One cross-sectional study determined sodium intake is positively correlated with BP levels and mean arterial pressure. A second cross-sectional study showed a positive correlation with BP levels and pulse pressure. One cohort study found a weak correlation between sodium excretion and SBP.  

• Grade I means there is Good/Strong evidence supporting the statement;
• Grade II is Fair;
• Grade III is Limited/Weak;
• Grade IV is Expert Opinion Only;
• Grade V is Not Assignable.
• High (A) means we are very confident that the true effect lies close to that of the estimate of the effect;
• Moderate (B) means we are moderately confident in the effect estimate;
• Low (C) means our confidence in the effect estimate is limited;
• Very Low (D) means we have very little confidence in the effect estimate.
• Ungraded means a grade is not assignable.

One negative-quality cohort study in 90 Asian Indian children, two to 18 years of age, studied the association between sodium intake and the incidence of hypertension (HTN). Children with a parent or grandparent with essential HTN had a 30% greater incidence of HTN and significantly higher sodium intake than those in the control group without hypertensive family members. More research in this area is needed.

• Grade I means there is Good/Strong evidence supporting the statement;
• Grade II is Fair;
• Grade III is Limited/Weak;
• Grade IV is Expert Opinion Only;
• Grade V is Not Assignable.
• High (A) means we are very confident that the true effect lies close to that of the estimate of the effect;
• Moderate (B) means we are moderately confident in the effect estimate;
• Low (C) means our confidence in the effect estimate is limited;
• Very Low (D) means we have very little confidence in the effect estimate.
• Ungraded means a grade is not assignable.

Depletion and loading methods were used for determining salt sensitivity in the clinical setting. A significant relationship of blood pressure (BP) response to salt/sodium (Na) depletion and load was observed. In adults with varying levels of BP, a dietary or an intravenous (IV) method of Na depletion (10 to 50mmol per day, three days or less) and Na loading (150 to 400mmol per day, three days or more), both with BP monitoring throughout the test period, provide strong evidence that this is an acceptable method. 

• Grade I means there is Good/Strong evidence supporting the statement;
• Grade II is Fair;
• Grade III is Limited/Weak;
• Grade IV is Expert Opinion Only;
• Grade V is Not Assignable.
• High (A) means we are very confident that the true effect lies close to that of the estimate of the effect;
• Moderate (B) means we are moderately confident in the effect estimate;
• Low (C) means our confidence in the effect estimate is limited;
• Very Low (D) means we have very little confidence in the effect estimate.
• Ungraded means a grade is not assignable.

In six out of seven studies that included adolescents (age 13 to 16 years) and adults, potassium (K) significantly affected the relationship between sodium (Na) and blood pressure (BP). A greater effect of K on the Na-BP relationship was observed in the following groups: Subjects with salt-sensitivity, black subjects, females, and in older subjects.

* In some studies, PHTN may also include NTN, due to changes in the definition of each.

• Grade I means there is Good/Strong evidence supporting the statement;
• Grade II is Fair;
• Grade III is Limited/Weak;
• Grade IV is Expert Opinion Only;
• Grade V is Not Assignable.
• High (A) means we are very confident that the true effect lies close to that of the estimate of the effect;
• Moderate (B) means we are moderately confident in the effect estimate;
• Low (C) means our confidence in the effect estimate is limited;
• Very Low (D) means we have very little confidence in the effect estimate.
• Ungraded means a grade is not assignable.

Limited research indicates mixed results regarding the relationship between mineral interactions and other dietary factors on the sodium and blood pressure (BP) relationship. Two studies found that calcium (10 to 25mmol per day) and potassium (10 to 60mmol per day) prevented the age-related rise in BP in children who were salt-sensitive or improved BP control in adults on less than 2,400mg per day sodium diet. A third study failed to show a relationship. More research is needed to clarify the relationship.

• Grade I means there is Good/Strong evidence supporting the statement;
• Grade II is Fair;
• Grade III is Limited/Weak;
• Grade IV is Expert Opinion Only;
• Grade V is Not Assignable.
• High (A) means we are very confident that the true effect lies close to that of the estimate of the effect;
• Moderate (B) means we are moderately confident in the effect estimate;
• Low (C) means our confidence in the effect estimate is limited;
• Very Low (D) means we have very little confidence in the effect estimate.
• Ungraded means a grade is not assignable.