Dr. Li Yang‘s fellowship work was funded from November 2008 to June 2009. During that time, she explored how dietary sodium and potassium regulate blood pressure. Changing the dietary ratio of potassium to salt has a beneficial effect on hypertension (which affects 1 in 3), chronic kidney disease (which affects 1 in 8), and metabolic syndrome (affecting 1 in 4). Other studies in this area have focused on the effects of completely removing potassium from the diet or the effects of raising sodium to very high levels. Few studies have examined the ratio between potassium and sodium. Almost no studies were found that compare a typical Western diet with an optimal diet recommended by the American Heart Association.
The central goal of Dr. Yang’s research was to rigorously investigate various diets which contain sodium and potassium and their effects upon blood pressure, renal disease, and metabolic syndrome.
Dr. Yang, an expert in cell biology as well as animal physiology, researched the mechanisms that cause these benefits through studies with laboratory rats. Her research did indeed show that a high potassium diet lowers blood pressure. The data suggest that this occurs by inhibiting sodium reabsorption in the proximal tubule of the kidney, leading to increased salt excretion. Most interestingly and counterintuitively, she found that the beneficial effect of high potassium is even greater if there is high sodium in the diet. If these findings can be extrapolated to humans, it suggests that there should be a much greater focus in public health efforts on increasing dietary potassium intake, rather than simply restricting dietary sodium.
To learn more, read Li Yang’s full project summary.