The findings are based on a study of 3,303 people and were presented last week at the American Society of Nephrology's annual meeting in Philadelphia.
Half of the people who took part in the study were African American, a group known to consume the lowest amounts of potassium in their diet.
After analysing urine samples, the researchers found that the level of potassium in the urine was strongly associated with BP. The effect of potassium on BP was even stronger than that of sodium.
The relationship between low potassium levels and high BP remained significant even after adjusting for age, race and other cardiovascular risk factors such as diabetes and smoking.
Lead researcher Dr Susan Hedayati, from the University of Texas Southwestern Medical Centre, said: 'There has been a lot of publicity about lowering salt in the diet to lower BP, but not enough on increasing dietary potassium.'
Consuming more high-potassium foods such as bananas and citrus fruits in the diet may help to lower BP, added Dr Hedayati.
- American Society of Nephrology's 41st annual meeting, Philadelphia.
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