Salty Foods Induce Hunger Not Thirst, New Study Reveals
It was believed that salty foods induce thirst. But an international group of scientists discovered a precisely opposite theory during a simulated mission to Mars.
According to a new study published in The Journal of Clinical Investigation, scientists tested the old belief that people became thirsty when they eat salty foods. They studied the association between salt consumption and drinking routines on a simulated undertaking to Mars. The team is from the Max Delbrûck Center for Molecular Medicine in Germany and Vanderbilt University in the U.S. city of Nashville.
According to Science Daily, the study involved two sets of ten male volunteers for two simulated flights to Mars. These participants were sealed in an artificial spaceship. The scientists observed the first group for 105 days and the second for 205 days.
All participants were given similar kinds of food except that over the periods of several weeks, they consumed foods with three different level of salt content (6, 9 and 12g). The scientists then found that consuming more salty foods cause an increased volume of urine with a higher salt level. However, the participants' elevated urine output was not due to frequent drinking of water.
In fact, those who ate foods containing 6 grams to 12 grams of salt drank less, the study revealed. Salt was known of activating a body's mechanism to store water in the kidneys instead.
The original hypothesis stated that charged sodium and chloride ions contained in salt from water molecules were dragged into the urine. But the latest study discovered that salt stayed in the urine while water returned to kidneys and to other parts of the body.
As a result, the scientists need to modify their view of urea, which is a product made in muscles and the liver due to nitrogen excretion. Urea accumulates in the kidneys where withdrawals of the sodium and chloride ions were being neutralized as observed in experimental mice.
Nevertheless, production of urea requires energy and this explains why the laboratory animals given with high-salt diet have an increased craving to foods. Consuming salty foods did not make them thirsty; rather they became more hungry.