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- A new study published in eBioMedicine found adults with higher levels of sodium in their blood are more likely to age quicker, develop chronic disease, and experience premature death.
- Finding out how much water you need each day, and hitting that goal, can help prevent and slow the development of chronic disease and premature death.
Yet another study associates adequate hydration with living a long and healthy life. New research published in eBioMedicine found that staying well-hydrated may help adults prevent or slow the progression of chronic diseases and premature death.
Researchers collected more than 25 years of health data from 11,255 adults, ages 45 to 66, to explore links between hydration, aging, chronic disease, and death.
Natalia Dmitrieva, Ph.D., study author and researcher at the National Heart, Lung, and Blood Institute (NHLBI) tells Runner’s World, she and her colleagues utilized blood sodium levels to measure hydration because the electrolyte is directly involved in the body’s water regulation cycle. When we drink less fluid, the concentration of sodium throughout the body increases, she says. When we drink lots of water, our sodium levels decrease.
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The study found participants with serum (blood) sodium levels above 144 millmoles per liter (mmol/l), were 50 percent more likely to have a higher biological age (as shown by accelerated damage to tissues and cells throughout the body, Dmitrieva explains), compared to those with sodium levels between 137 and 142 mmol/l.
Researchers also associated sodium levels of 140 mmol/l and higher with a 63 percent increased odds of developing chronic diseases, when compared to those with 138 to 140 mmol/l sodium levels (a narrow range within what experts consider normal). Finally, those with sodium levels slightly above the 138 to 140 mmol/l range and those slightly below those numbers saw an associated and significantly increased risk of premature death.
The takeaway: Participants with blood sodium levels within a narrow normal range—and therefore, had optimal hydration—showed the healthiest advantages. More specifically, sodium levels between 137 and 142 mmol/l were associated with the lowest risk of early mortality and sodium levels between 138 to 140 mmol/l were linked to the lowest risk of chronic disease.
Ultimately, Dmitrieva says, adults who don’t drink enough water are more likely to develop chronic disease or experience premature death because our bodies try to conserve water when we don’t drink enough. Therefore chronic dehydration gradually undermines the body’s proper functions and leads to accelerated aging.
“These findings are important for people of all ages, since worldwide population surveys estimate that more than 50 percent of people drink less than recommended [amounts of water] and are therefore hypohydrated,” or dehydrated, says Dmitrieva.
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How can you monitor your hydration status?
While you probably won’t get your blood sodium levels measured on the daily, there are other ways you can make sure you’re drinking enough.
Thirst is a common indicator of hydration status, however, as Dmitrieva mentioned, it isn’t always the most reliable. The next time you go to the bathroom, look at the color of your urine as it, too, can tell you if you’re drinking enough fluid.
“Low water intake stimulates the secretion of hormones that act on kidneys, leading to the excretion of lower volumes of more concentrated urine. Therefore, dark yellow urine could indicate that we do not drink enough,” says Dmitrieva.
Also, serum sodium levels are typically a routine part of your annual physical exam, so consult with your primary care doctor if you’re interested in finding out more about your hydration status, as they can clue you into whether you need to be consuming more fluids.
How much water should endurance athletes drink?
Proper hydration is crucial for endurance athletes because the body exerts fluid and electrolytes through sweat as you exercise.
In general, most people should drink about 60 to 80 ounces of water a day. But, Dmitrieva says, endurance athletes may need to drink more because these recommendations don’t account for exercise or heat exposure. This is why athletes should consult with an expert about how much fluid they need consume on a day-to-day basis, rather than trying to calculate it themselves.
In terms of fluid replenishment after exercise, there are many different factors runner need to consider including sweat rate, environment, body size, exercise intensity, and personal preferences, according to guidelines published by the National Athletic Trainers Association.
What’s more, it’s important for runners to identify their specific needs to avoid over-hydrating, in addition to under-hydration, because it can also be dangerous in extreme cases. “If the kidney cannot excrete excess water, the sodium content in the blood becomes diluted. This is called hyponatremia and it can be life-threatening,” says Dmitrieva.
The bottom line on the importance of hydration
This study reiterates that proper hydration is key for overall health. Consider pairing up with registered dietitian who is certified in sports dietetics to help you properly identify and meet your hydration needs.
Monique LeBrun joined the editorial staff in October 2021 as the associate health and fitness editor. She has a master’s degree in journalism and has previously worked for ABC news and Scholastic. She is an avid runner who loves spending time outside.
