Author Interviews, Blood Pressure - Hypertension, JAMA, Salt-Sodium / 29.04.2015
Potassium May Play Larger Role Than Sodium in Adolescent Blood Pressure
MedicalResearch.com Interview with:
Lynn L. Moore, DSc, MPH
Department of Medicine
Boston University School of Medicine
Boston, Massachusetts
Medical Research: What is the background for this study?
Dr. Moore: The USDA’s current Dietary Guidelines for sodium intake have become increasingly controversial. Current recommendations include restricting sodium intake after the age of 2 years to no more than 2300 mg per day. For African-American adults and children, intakes should be restricted to no more than 1500 mg per day. Actual intake levels are much higher, with most Americans consuming about 3500 mg per day. Our goal was to estimate the effects of dietary sodium and potassium intakes on the change in blood pressure throughout adolescence.
We used data from the National Growth and Health Study, a prospective study of more than 2000 girls who were 9-10 years of age at the time of enrollment. Lifestyle factors were assessed repeatedly throughout the study, and blood pressure was measured annually. Dietary sodium and potassium were assessed using multiple sets of three-day diet records. We used longitudinal modeling to estimate the effects of dietary sodium and potassium on blood pressure change over 10 years.
Medical Research: What are the main findings?
Dr. Moore: In this study, there was no evidence for a beneficial effect of reduced sodium intake on blood pressure change during adolescence. By 19-20 years of age, girls who consumed more than 4000 mg of sodium per day had systolic and diastolic blood pressure levels that were similar to those seen among girls with lower levels of sodium intake. Specifically, there was no beneficial effect on blood pressure associated with sodium intakes of less than 2500 mg per day. These results were similar for blacks and whites. In contrast, the repeated measures analyses showed that girls who consumed more than 2400 mg of potassium per day had lower blood pressures throughout adolescence compared with girls consuming less than 1800 mg per day of potassium.
(more…)