Medical experts dispute the importance of curtailing dietary salt. Experts focused on blood pressure favor cutting salt. Experts focused on reducing heart attacks and protecting cardiovascular health disagree and favor an approach of improving overall dietary quality. A new study suggests the 30-year debate may have been irrelevant; human physiology has multiple systems that ensure proper intakes of salt and water to protect health. As Mort summarized recently on SaltSensibility , the body has redundant systems and is self-regulating. No matter what the experts may advise, our unique consumption level for salt is "hard-wired" into our systems to protect our health against do-gooder meddling:
This latest publication shows that this multi-factorial system is so robust and includes so many failsafe mechanisms that it continues to fully function even after large sections of its system are shut down. Employing a complex cascade of physiological functions from powerful hormones, such as aldosterone, to pressure sensitive receptors in the brain, this water thirst and salt appetite mechanism moderates our behavior so that we are driven to quickly replenish the volume and ionic balance of our blood, so that it is pressurized sufficiently for our heart to circulate it through our bodies. When fluids and electrolytes are lost, such as with sweating, physical exertion, diarrhea or other circumstances, we immediately get a water thirst signal. So we drink water to make up the loss. After a delay, our salt appetite kicks in to ensure that the ion levels are replaced. If we don't respond on time to the salt appetite, we die.
The article, "Central regulation of sodium appetite " appears in the February issue of Experimental Physiology.
