We all know people who regularly snarf 7-Eleven’s finest snack items yet never have to worry about their blood pressure. They might have reason to worry after all, according to a new review of research.
University of Delaware researchers conducted a review of research on sodium’s effects and found that even if blood pressure is normal, salt can adversely affect key organs. The paper was published in the Journal of the American College of Cardiology and noted on sciencedaily.com.
“Blood pressure responses to alterations in dietary sodium vary widely, which has led to the concept of ‘salt-sensitive’ blood pressure,” one of the paper’s authors, William Farquhar, of UD’s Department of Kinesiology and Applied Physiology told UDaily. “There are no standardized guidelines for classifying individuals as having salt-sensitive blood pressure, but if blood pressure increases during a period of high dietary sodium or decreases during a low-sodium period, the person is considered salt sensitive. If there’s no change in blood pressure with sodium restriction, an individual is considered salt resistant,” he said.
But the paper pointed out research that offered evidence of negative effects on multiple target organs and tissues, even for people who are salt resistant. Which ones? The biggies: heart, kidneys, brain and blood vessels.
The research found that sodium may also affect the sympathetic nervous system, which activates the “fight-or-flight response.”
“Chronically elevated dietary sodium may ‘sensitize’ sympathetic neurons in the brain, causing a greater response to a variety of stimuli, including skeletal muscle contraction,” Farquhar says. “Again, even if blood pressure isn’t increased, chronically increased sympathetic outflow may have harmful effects on target organs.”
Some people have shifted their concern from salt to sugar. Recent research suggests the sweet stuff may have a greater role than salt in high blood pressure and heart disease.