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Water, Hydration, and Serum Sodium

By Gary F. Zeolla


      Water is the most basic of all beverages. However, there are many issues related to its consumption that many might not have thought about. This article will cover these water-related issues by way of looking at various news articles and studies about water and related issues.


News Articles and Studies


CNN. Hydration can significantly impact your physical health, study finds.


      You may know that being adequately hydrated is important for day-to-day bodily functions such as regulating temperature and maintaining skin health.

      But drinking enough water is also associated with a significantly lower risk of developing chronic diseases, a lower risk of dying early or lower risk of being biologically older than your chronological age, according to a National Institutes of Health study published Monday [1/2/23] in the journal eBioMedicine.

      “The results suggest that proper hydration may slow down aging and prolong a disease-free life,” said study author Natalia Dmitrieva, a researcher in the Laboratory of Cardiovascular Regenerative Medicine at the National Heart, Lung and Blood Institute, a division of NIH, in a news release.


      The study this article cites is Middle-age high normal serum sodium as a risk factor for accelerated biological aging, chronic diseases, and premature mortality. It states:


      It is known that some people age faster than others, some people live into old age disease-free, while others develop age-related chronic diseases. With a rapidly aging population and an emerging chronic diseases epidemic, finding mechanisms and implementing preventive measures that could slow down the aging process has become a new challenge for biomedical research and public health. In mice, lifelong water restriction shortens the lifespan and promotes degenerative changes. Here, we test the hypothesis that optimal hydration may slow down the aging process in humans….

      People whose middle-age serum sodium exceeds 142 mmol/l have increased risk to be biologically older, develop chronic diseases and die at younger age. Intervention studies are needed to confirm the link between hydration and aging….

      Since decreased hydration is one of the main factors that elevates serum sodium, the results are consistent with hypothesis that decreased hydration may accelerate aging. However, interventional trials are needed to prove this link.


      Serum (or blood) sodium levels are generally checked as part of a basic blood test done with a yearly physical or “wellness visit.” Sodium might be listed in the results by its chemical symbol of Na, while salt is NaCl (sodium chloride).

      Normal serum sodium levels are 136 - 145 mmol/L. Thus, the 142 or above number being used in this study is within the normal range. However, this study found that even being at the high end of the normal range could be problematic.

      Note also the assumption is that the elevated sodium level is being caused by inadequate hydration. But there are other possible causes of elevated sodium levels, such as excessive sodium (salt) intake. Excessive sodium intake has other possible health risks, such as elevated blood pressure (hypertension) and resultant heart attacks and strokes. If you are in this upper range, talk to your doctor about those other possible causes and about drinking more water and/ or consuming less sodium.


Fox News. Staying hydrated may lower risk of heart failure, study says.


      Drinking water to maintain a healthy sodium level in the bloodstream may reduce the risk of heart failure, a chronic condition where the heart has difficulty pumping blood to match the body’s needs, according to a recent paper published in the European Heart Journal.

      Over 6.2 million Americans suffer from heart failure, which is more than 2% of the United States population and is more common in those ages 65 and older, according to a recent press release on the study….

      The Mayo Clinic notes healthy people maintain a sodium level between 135 and 145 mmol/L in the bloodstream, but as sodium increases, the body’s fluid levels decrease, so the researchers used sodium as a marker for fluid status to identify participants who had a higher risk for developing heart failure.

      “Heart failure risk was increased by 39% if middle age serum sodium exceeded 143 mmol/L [millimoles per liter], corresponding to 1% body weight water deficit,” the study authors noted (brackets in original).


      This study was similar to the previous one in that it used serum sodium levels to indicate hydration levels. But it focused on just one case of death, heart attacks, rather than all cause-mortality like the previous study. But its results were similar. Even being at just the high end of the normal range increased risk.

      The study itself is titled Good hydration may reduce long-term risks for heart failure. It found:


      Staying well-hydrated may be associated with a reduced risk for developing heart failure, according to researchers at the National Institutes of Health. Their findings, which appear in the European Heart Journal, suggest that consuming sufficient amounts of fluids throughout life not only supports essential body functioning but may also reduce the risk of severe heart problems in the future.    …

      … adults with serum sodium levels starting at 143 milliequivalents per liter (mEq/L) – a normal range is 135-146 mEq/L – in midlife had a 39% associated increased risk for developing heart failure compared to adults with lower levels. And for every 1 mEq/L increase in serum sodium within the normal range of 135-146 mEq/L, the likelihood of a participant developing heart failure increased by 5%....

      Fluids are essential for a range of bodily functions, including helping the heart pump blood efficiently, supporting blood vessel function, and orchestrating circulation. Yet many people take in far less than they need, the researchers said. While fluid guidelines vary based on the body’s needs, the researchers recommended a daily fluid intake of 6-8 cups (1.5-2.1 liters) for women and 8-12 cups (2-3 liters) for men. The Centers for Disease Control and Prevention also provides tips to support healthy hydration.


      Again, these studies are looking at sodium levels at the upper level of the normal range. Assumedly, having sodium levels above the normal range would be even more problematic. But I would guess that was already known. What this means is, even if your blood tests results do not flag your sodium levels as being above the normal range, if they are at the upper end, you might want to increase your water intake and talk to your doctor about other steps to reduce you heart attack risk.

      However, I always find it quite strange when blanket recommendations are given for water intakes, given that variant body sizes and activity levels can affect needs. There is no way my ideal water intake (at 5’0” and 120 pounds working out in my air-conditioned home gym) would be the same as a Pittsburgh Steelers lineman (at say 6’6” and 300 pounds and doing two a day August workouts outdoors).

      However, that is why these two studies looked at sodium levels rather than water intake. And differing activity levels and conditions are mentioned in the article from the CDC mentioned in the study. It is Water and Healthier Drinks. It states:


      Getting enough water every day is important for your health. Drinking water can prevent dehydration, a condition that can cause unclear thinking, result in mood change, cause your body to overheat, and lead to constipation and kidney stones. Water has no calories, so it can also help with managing body weight and reducing calorie intake when substituted for drinks with calories, such as sweet tea or regular soda.


Water helps your body:


         Keep a normal temperature.

         Lubricate and cushion joints.

         Protect your spinal cord and other sensitive tissues.

         Get rid of wastes through urination, perspiration, and bowel movements.


Your body needs more water when you are:


         In hot climates.

         More physically active.

         Running a fever.

         Having diarrhea or vomiting.


GPOA. How to Prevent Injuries in Sports: 10 Ways to Prevent Injuries.


      It's important for all athletes to stay properly hydrated, especially in hot weather. The American College of Sports Medicine (ACSM) recommends that athletes drink 17-20 ounces of water 2-3 hours before exercise, 7-10 ounces of water every 10-20 minutes during exercise, and 16-24 ounces of water for every pound lost after exercise.


      The preceding quote is not from a news article but from a mailing I received from the office of the orthopedic surgeon that performed my two recent shoulder surgeries. The article is about preventing injuries not about hydration per se. But I found it interesting that proper hydration was listed as one of the ten ways to prevent injuries.

      The article does not explain just how improper hydration could lead to injury. But that might be hinted at in the preceding quote from the CDC article when it says water can  “Lubricate and cushion joints” and even that low hydration levels can “cause unclear thinking.” I would add dizziness. Not thinking straight and feeling dizzy could cause you to fall or do something stupid, leading to an injury.


Newsmax. Most Americans Don't Drink Enough Water.


      Up to 75% of Americans do not drink enough water. Drinking water is important because even mild dehydration can affect every part of your body, from your gut to your brain. A survey of 3,003 U.S. adults found that three-quarters of the respondents had a net fluid loss, resulting in chronic dehydration. Although the survey found that many Americans do drink about eight servings of hydrating beverages daily, this is offset by drinking caffeinated beverages and alcohol and eating a high sodium diet….

      According to Axios, the U.S. National Academies of Sciences, Engineering, and Medicine recommends that men drink about a gallon of water daily and the average woman should consume three-quarters of a gallon. A gallon is 128 ounces or 16 eight-ounce glasses of water. While you do get about 20% of your daily water intake from food, the rest you need to get from drinking.


      A gallon of water is a lot of water, and there is no way someone my size could drink that much water. If I did, I would have to urinate every hour, including during the night. Again, body size and activity levels and conditions need to be considered when giving water intake suggestions.

      That said, note the point about caffeinated beverages and alcohol being dehydrating. That means, coffee and tea and various alcoholic beverages should not be counted as part of one’s daily fluid intake. A diet high in salt is also dehydrating. That is one of the ways excessive salt intake can be deleterious.


Newsmax. How to Reduce Risky Nighttime Bathroom Breaks.


      Those nocturnal trips to the restroom may be harmful to your health, especially if you are over 65. The occasional urge to pee during the night might be triggered by drinking too may [sic, many] fluids close to bedtime or by certain medications. However, nocturia, a condition that causes you to wake up frequently to urinate becomes more common as people age and occurs in both men and women. This bothersome bladder condition can increase your risk for falling and serious injury….

      “The simplest thing to do is to avoid fluids after dinner and avoid bladder irritants in the evening, including caffeine, carbonated beverages, and alcohol,” says [Dr. Karyn] Eilber [a board-certified urologist]. She adds that people who are light sleepers and head for the bathroom just because they are awake, should talk to their doctor about ways to improve the quality of their sleep.


     This article is a good follow-up to my mentioning about getting up at night to urinate if I drink too much water. Also, as mentioned here, drinking water after dinnertime can lead to those nighttime trips. I have found that to be true in my case and learned a long time ago not to drink any fluids in the evenings.


Newsmax. Beyond Water: The Most Hydrating Foods and Drinks.


      According to experts, drinking water isn’t the only way to get enough daily fluids. Foods and drinks that are also hydrating.


     This article then lists and discusses the following foods and beverages as being hydrating: oatmeal, milk, smoothies, fruits and vegetables, frozen fruit, cold soup, and tea and coffee. However, on the latter two is the caveat, “not to overdo the espresso as this can have a diuretic effect and dehydrate the body.” Again, caffeine can increase urination, so that could offset the water contained in coffee and tea. But that would probably be more the case for coffee than tea given its higher caffeine content.


Newsmax. Best Foods and Drinks to Stay Hydrated for Summer Exercise.


      “For summer workouts, it's important to make sure that adequate carbohydrates, fluids and electrolytes are consumed,” said sports dietitian Kristen Chang, assistant director of the master's program in nutrition and dietetics at Virginia Tech University….

      That means you need to think about what you eat and drink before a workout to account for increased water loss from sweat.

      This can include boosting your intake of fluids and electrolytes, or foods with a higher water content, including melons such as watermelon, cantaloupe and honeydew; and soups, smoothies, apples, berries, pineapple, bell peppers, tomatoes and celery.

      Pay careful attention to hydration before and after workouts, Chang recommended….

      Also, it's “really important to include a quality source of electrolyte, which could be in the form of a sports drink or salty foods to complement water,” Chang said….

      To replenish energy after a workout, eat a snack or meal that includes easily digestible carbohydrates and protein.


      A discussion of pre- and post-workout nutrition is out of the scope of this article, but it is covered in my book Starting and Progressing in Powerlifting. But here, the water content of foods and drinks other than water does need to be considered when calculating your total fluid intake. However, water itself should always be your main source for hydration.


MSM. 9 Telling Signs You’re Drinking Too Much Water, From Nutrition Experts.


      Health authorities have educated us that drinking enough water is absolutely vital for our bodies to function properly. And it is—unless you drink too much of it. Though most people look out for the signs of dehydration, experts say overhydration can be equally as dangerous.

      Drinking too much water generally results in nothing worse than a frequent flier pass to the restroom—but under certain circumstances, it can cause extreme illness and even death, says Austin DeRosa, MD, urologist with UCHealth Cancer Center in Highlands Ranch, Colorado and chair of robotic surgery at the University of Colorado Medicine. Hyponatremia, sometimes called “water intoxication,” causes abnormally low levels of sodium and other electrolytes in your bloodstream, which then can lead to serious health problems such as seizures, coma, and, in rare cases, is fatal, he explains….

      Read up on the signs of overhydration from recognized clinical leaders.


      The nine signs are:

1.       You never leave the house without a water bottle and constantly have one in hand.

2.       You have throbbing headaches throughout the day.

3.       You lose the urge to urinate.

4.       You drink water even when you’re not thirsty.

5.       Your urine looks like water.

6.       You urinate frequently, including during the night.

7.       You experience leakage.

8.       You vomit or experience diarrhea or nausea.

9.       You notice swelling or discoloration in your hands, lips, and feet.


      Water and hydration are important, but some have a tendency to overdo a good thing. Each of these points are worth noting. If you display any of them, you might want to consider your water intake. This MSM article provides an explanation of each point.

      But Point 5 is the most important for our discussion. It is the simplest way to know if you are drinking too much or too little water. Urine should have a pale-yellow color and a slight odor. If it is mostly clear and has no odor, you are probably drinking too much. If it is a dark yellow and has a strong odor, you are probably drinking too little.


      This point was made in the previous Newsmax article:

      Keep track of your hydration status, she noted.

      “An easy way to do that is to monitor the color of your urine. If it's dark and concentrated and you're not going to the bathroom much, you need to drink more fluids,” Chang said. “If your urine is consistently clear and you're making frequent pit stops, you may be overhydrating.”


My Serum Sodium Levels and Fluid Intake


      I have had chronically low sodium levels for many years, going back to at least 2015. It is usually around 134-135. My doctor has told me to drink less water, thinking I am over-hydrated. I have tried to do so, but I find drinking less water to be very difficult to do.

      I tried the opposite, consuming more sodium. That did increase my serum sodium levels into the normal range with a reading of 139, but it also increased my blood pressure to an above normal 142/ 92 at my September “wellness visit” at my doctor’s office last year (2022).

      I went back to less sodium over the past year. At my appointment this September (2023), my sodium levels were once again down to 134, but my blood pressure was back down to a normal 122/80. It seems to me that high blood pressure is more of an issue than low sodium levels, so I will stick with the reduced sodium intake, while keeping my water intake the same.

      That would be about eight (8-ounce) cups of fluids a day. That includes the water I use to make my morning oatmeal and my pre- and post-workout drinks and two cups of tea a day. If the caffeine in the tea cancels out the fluid intake, then I would only be consuming six cups a day. But again, my serum sodium levels are chronically low. Thus, most likely that amount is more than adequate for someone of my size and activity level.

      But that former number is 64 ounces or half a gallon. If I drink more than that, I am urinating frequently, even at night. That is why I found the gallon a day recommendation quite strange.




      Water is the most basic of beverages, while proper hydration is important for both short-term and long-term health. However, both under-hydration and over-hydration can be problematic. Having your serum sodium levels checked will give you an objective idea of your hydration status. But the other though more subjective indicators mentioned in this article are worth noting as well. However, talk with your doctor before changing your water or salt intake levels to decide what is best for your unique health situation.


Creationist Diet: Second Edition

Water, Hydration, and Serum Sodium. Copyright 2023 By Gary F. Zeolla.

Disclaimers: The material presented in this article is intended for educational purposes only. The author is not offering medical or legal advice. Accuracy of information is attempted but not guaranteed. Before undertaking any diet, exercise, or health improvement program, one should consult your doctor. The author is in no way responsible or liable for any bodily harm, physical, mental, or emotional, that results from following any of the advice in this article.

The above article was posted on this site October 1, 2023.
It originally appeared in the free email newsletter FitTips for One and All.

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