According to a new study, low potassium levels in the urine can contribute to high blood pressure. The lead author of the study Susan Hedayati, MD, of the University of Texas Southwestern Medical Center in Dallas, Texas, and the Dallas VA Medical Center said, "There has been a lot of publicity about lowering salt or sodium in the diet in order to lower blood pressure, but not enough on increasing dietary potassium."

In the study, researchers analyzed data on 3,300 subjects half of whom were African American, to see if a low potassium level in the urine was linked to high blood pressure. The effects were studied regardless of the level of salt (sodium) in the diet or cardiovascular risk factors.  The results of the study showed that potassium amounts in the urine were strongly linked to blood pressure.

"The lower the potassium in the urine, hence the lower the potassium in the diet, the higher the blood pressure," Hedayati noted. "This effect was even stronger than the effect of sodium on blood pressure."This observation "supports the hypothesis that dietary potassium deficiency plays an important role in the development of high blood pressure," added Hedayati.

In the findings presented over the weekend at the American Society of Nephrology's annual meeting in Philadelphia, the researchers also reported racial differences in the blood pressure also referred to as hypertension and its relationship with to potassium levels in the diet being seen. "Our study included a high percentage of African-Americans, who are known to consume the lowest amounts of potassium in the diet," Hedayati said. "The association was stronger in African Americans than non-African Americans,” said the researchers.

The researchers reported that they found individuals with hypertension were older, heavier, had lower levels of potassium in their urine and were more likely to be African American. These subjects also had lower glomerular filtration rates, which correlates with poor kidney function.

Hedayati mentioned Dr. Chou-Long Huang, one of the co-investigators on the study who found evidence of a specific gene called WNK1which could be responsible for potassium’s effect on blood pressure. "We are currently doing more research to test how low potassium in the diet affects blood pressure through the activity of this gene," Hedayati said.