How Does Sodium Cause Both Dehydration AND Water Retention?
It seems counterintuitive that consuming too much salt (sodium chloride) could cause you to feel bloated due to “retaining water” yet also result in increased thirst and dehydration. What gives?
The answer lies not in what excess sodium does to our bodies as a whole, but how our bodies react to excessive sodium levels by changing where and how water is stored.
Excessive Sodium Levels
When sodium levels in our bodies become excessive, sensors in our heart and bloodstream alert the kidneys that sodium must be excreted to return blood (plasma) sodium levels to normal. Because water is needed to excrete the sodium, water is taken primarily from cells in our skin and skeletal muscles to go to our digestive tract and kidneys in an effort to filter out the sodium.
As a result, fluid can accumulate in the lower abdominal region, while cells in our skin and skeletal muscles become dehydrated, which can lead to dry skin, increased feelings of thirst, and muscle tightness or cramps.
Once plasma sodium levels return to normal, the cells that are dehydrated can be re-hydrated by increased fluid intake. If you regularly experience bloating or symptoms of dehydration, focus on decreasing your sodium consumption by limiting processed foods and foods that list sodium as a preservative, especially if you have high blood pressure.
Please note that the terms “dehydration” and “fluid retention” used above are referring to mild cases of water imbalance. In more serious cases dehydration may be related to inadequate fluid intake or excessive diuretic use, and fluid retention (or edema) may be due to kidney or liver dysfunction.
These can be serious medical conditions that require more than just increased water intake and decreased sodium intake for treatment.
For help with managing your salt intake and planning lower sodium meals, leave me a comment or send me an e-mail!