You know that famous line from the show "Seinfeld": "These pretzels are making me thirsty!" Turns out, those pretzels weren't making him thirsty. In fact, salty foods don't make us thirsty at all. Wait, what?
I think I know when something is making me thirsty. Don't I? According to Munchies, a team of researchers from a few different institutions got together and examined a group of 10 male volunteers, divided into two groups. Group one was examined over the course of 105 days, while group two was examined over a course of 205 days. The men all followed the same diet, except with different levels of salt in their food.
Results came in showing that those who ate more salt produced more urine, and that urine contained more salt. Okay, no biggie. However, the weird part was that those who consumed more salt did not, in fact, drink more water. As it happens, they drank less water.
Daily Mail reports that the findings showed that salt was triggering a mechanism to conserve water in the kidneys. Before the experiment, the belief was that charged sodium and chloride ions in salt grabbed onto water molecules and dragged them into urine. Instead, salt stayed in the urine, while water moved back into the kidneys and body. Imagine that! Eating salty foods … helps keep you hydrated?
A substance called urea that is formed in the muscles and liver was thought to simply be a substance of waste that held no real value, was actually proven to do much more. In a study using mice, scientists found that those with the higher salt diets had urea accumulating in the kidneys, where it counteracts the water-drawing force of sodium and chloride. This process takes a lot of energy, so rather than making us thirsty, overly salty diets actually make us hungry.
This experiment has changed the way scientists view urea, but, more important, it has changed the way they had thought about how the body achieves water homeostasis -- how the body maintains proper balance, in other words.
In essence, what all of this really means, is that no, those pretzels aren't making you thirsty. They could, however, be making you hungry.