A recent study in Australia revealed that 30 minutes after you eat a salty snack, arteries become temporarily impaired, compromising the ability of blood vessels to widen even in people with normal blood pressure.
After the snacks were consumed, the volunteers were asked to put their arms in a blood pressure cuff, which temporarily cut off blood flow as it inflated. While the cuff was deflating, the researchers used an ultrasound machine to measure how much the arteries widened as the blood rushed back through them. The same experiment was repeated with the two groups of volunteers switched so that people who got a high salt snack the first time consumed the low salt version the second time.
Consistently, the arteries of people who got the high salt snack widened about half as much as those who consumed the low salt version. The effect passed in about two hours.
Substances like salt and fat may hinder the artery’s ability to widen by interfering with the workings of the blood vessel’s lining, said Dr. Emile Mohler, director of vascular medicine at the University of Pennsylvania Health System. Normally, when the heart pumps blood through the arteries, nitric oxide is released. The gas makes the artery walls relax, which in turn allows the vessels to expand and more easily carry the rush of blood, Mohler explained. Scientists suspect that salt and fat may somehow block the release of nitric oxide.