January 28, 2009
Potassium may help lower blood pressure
People trying to lower their blood pressure should also boost their intake of potassium, which has the opposite effect to sodium, a U.S. study suggests.
Senior author Dr. Paul Whelton, an epidemiologist and president of Loyola University Health System, and colleagues found that the ratio of sodium-to-potassium in subjects' urine was a much stronger predictor of cardiovascular disease than sodium or potassium alone.Researchers determined average sodium and potassium intake during two phases of a study known as the Trials of Hypertension Prevention. The researchers collected 24-hour urine samples intermittently during an 18-month period in one trial and during a 36-month period in a second trial.
The 2,974 study participants -- initially ages 30-54, and with blood pressure readings just under levels considered high -- were tracked for 10-15 years to see if they would develop cardiovascular disease.
The study, published in the Archives of Internal Medicine, found those with the highest sodium levels in their urine were 20 percent more likely to suffer strokes, heart attacks or other forms of cardiovascular disease compared with their counterparts with the lowest sodium levels. However this link was not strong enough to be considered statistically significant.
By contrast, participants with the highest sodium-to-potassium ratio in urine were 50 percent more likely to experience cardiovascular disease than those with the lowest sodium-to-potassium ratios. This link was statistically significant.