Can you slow down ageing by drinking water?

A new study suggests that not drinking enough water is linked to faster biological ageing and increased risk of premature death.
The researchers evaluated proper hydration by evaluating blood sodium, or salt, levels.
Study authors and GPs explain what to take away from this study.

Dehydration can lead to all sorts of health issues, such as fatigue, muscle cramps, lightheadedness, even chills. Now, new research shows that staying properly hydrated can significantly impact your health long-term, and even slow down the ageing process.

A study recently published in the journal eBioMedicine tested the hypothesis that optimal hydration may slow down the ageing process in humans. Using health data gathered from 11,255 adults over a 30-year period, researchers analysed links between levels of salt in the blood—which go up when fluid intake goes down—and various indicators of health. Data collection began in 1987 when participants were in their 40s or 50s, and the average age of participants at the final assessment during the study period was 76.

The researchers found that adults with salt levels at the higher end of a normal range were more likely to develop chronic conditions and show signs of biological ageing than those with salt levels in the lower ranges. Adults with higher salt levels were also more likely to die at a younger age. 

“The results suggest that proper hydration may slow down ageing and prolong a disease-free life,” said researcher Dr Natalia Dmitrieva.  

More specifically, researchers found that adults with higher salt levels in the blood—with normal ranges falling between 135-146 milliequivalents per litre (mEq/L)—were more likely to show signs of faster biological ageing. This was based on indicators like metabolic and cardiovascular health, lung function, and inflammation. Likewise, higher salt levels (144.5-146 mEq/L) had a 21% increased risk of premature death compared to ranges between 137-142 mEq/L. 

In addition to faster biological ageing and increased risk of early death, adults with salt levels above 142 mEq/L also had up to a 64% increased risk for developing chronic diseases like heart failure, stroke, atrial fibrillation and peripheral artery disease, as well as chronic lung disease, type 2 diabetes, and dementia. On the other hand, adults with salt levels between 138-140 mEq/L had the lowest risk of developing any chronic disease.  

As noted in the press release, the researchers noted that these findings do not prove causation, meaning that hydration alone is not proven to be the sole factor affecting these health outcomes.

How much water do you need?

According to the National Academy of Medicine, general recommendations for water intake have been set based on detailed national data, which showed that women who appear to be adequately hydrated consume an average of approximately 2.7 liters (91 ounces) of total water—from all beverages and foods—each day, and men average approximately 3.7 liters (125 ounces) daily.

Water is the most prevalent element in our body, and depriving our body of water will deprive it of its necessary functions, so we all need water to survive, says GP Dr David Cutler. “There’s a wide range of adequate water intake levels to achieve optimal health. At what point is too much or too little water is still an open question.”

The bottom line is that there is no specific required amount of daily water intake for adults, says Dr Cutler. However, it’s important to pay attention to signs of dehydration in your daily life that could lead to larger health concerns in the future.

Here are some important questions to consider, according to Dr Cutler:

Are you thirsty?
Are you not sweating when you’re hot?
Is your pee getting darker?

“Pay attention to these signs and when those happen, drink more water,” says Dr Cutler.

“The goal is to ensure patients are taking in enough fluids, while assessing factors, like medications, that may lead to fluid loss,” said study author Dr Manfred Boehm. She added that when advising people to properly hydrate, “doctors may also need to defer to a patient’s current treatment plan, such as limiting fluid intake for heart failure.”  

The bottom line

“At the end of the day, the question [the researchers are] asking ‘does poor hydration lead to worse health outcomes?’” says Dr Cutler.

“Being less hydrated will tend to cause your sodium level or salt level in your blood to go up,” says Dr Cutler. He adds that people with extremely high salt levels display signs of faster biological ageing.

“Having those increased levels of biological ageing led to certain chronic diseases like dementia, atrial fibrillation, heart failure and chronic lung disease and we know having those diseases will cause you to die prematurely,” says Dr Cutler. Still, it’s important to remember that there are several steps in between staying properly hydrated and dying prematurely, “so you can’t draw the conclusion that causation,” he adds.