Understanding Sodium's Link to Hypertension

Scientists have found a method for measuring sodium in the skin, which could help scientists better understand how too much of it leads to high blood pressure.

The American Heart Association recommends that sodium -- generally consumed in the form of table salt -- be limited to protect heart health, even for patients without high blood pressure. But the relationship between sodium and blood pressure is not certain.

Try to limit your daily sodium intake to 1500 mg.

Peter Linz  from the Friedrich-Alexander-University in Germany used a special MRI scanning technique for the first time, and tracked minute fluctuations in sodium levels in the skin of participants.

This is because the human skin appears to be a reservoir for salt, but very little was known about daily biological variations in skin, the differences between genders or how the effect of hormone changes would affect sodium levels in patients with high blood pressure.

The new technique was used in five volunteers who were between the ages of 25 and 68 years old. Investigators discovered that higher levels of sodium appeared to be linked to aging in men. The concentrations of sodium increased with age, from 41 millimoles per liter at the age of 25 to 58 millimoles per litter at the age of 68.

During their lifetime, 90 percent of Americans will suffer from high blood pressure. The American Heart Association recommends that individuals limit daily sodium consumption to 1500 mg, regardless of whether they have ever suffered from hypertension.

The study was recently presented at the American Heart Association's High Blood Pressure Research 2011 Scientific Sessions in Orlando, Fla.