We all know that it’s much better to be hydrated than dehydrated. Hydration is essential for bodily functions such as blood circulation, nutrient delivery and temperature regulation. But optimal hydration has other benefits. According to a National Institutes of Health study published Jan. 2, consuming enough water lowers the risk of developing chronic diseases, dying early and being biologically older than your chronological age.
“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 the National Institutes of Health.
Adults who aren’t sufficiently hydrated are more likely to age faster, face a higher risk of chronic diseases and be more likely to die younger than those who stay well-hydrated, according to the study, which collected data from more than 11,000 U.S. adults over 30 years.
With so many people in our society facing age-dependent chronic diseases–such as high blood pressure, arthritis, dementia, diabetes, kidney disease and stroke–learning what can prevent or slow down these conditions would help improve quality of life and lower healthcare costs.
The Study
The researchers thought that optimal hydration might slow down the aging process based on previous research showing that lifelong water restriction increased mice’s serum sodium and shortened their lifespan by six months (about 15 years of human life). For the new study, they looked at sodium levels in the participants’ blood because higher concentrations may indicate that they weren’t consuming enough fluids. Results showed that participants with high blood-sodium levels aged faster than those with lower levels.
Adults with serum sodium levels above 142 mEq/L had a 10% to 15% higher chance of being biologically older than their chronological age and a 64% higher risk for developing chronic diseases such as heart failure, stroke, atrial fibrillation, peripheral artery disease, chronic lung disease, diabetes and dementia. Those with levels above 144 mEq/L had a 50% higher risk of being biologically older and a 21% higher risk of dying early.
Biological age was determined by biomarkers that measure the performance of different organ systems and processes, including cardiovascular, renal, respiratory, metabolic, immune and inflammatory biomarkers such as high blood pressure, cholesterol and blood glucose.
The study analyzed participants over many years, but the findings don’t prove a causal relationship between serum sodium levels and these health outcomes, the authors said, noting that further studies are needed.
Are You Well Hydrated?
About 60% of the human body is water. Blood sodium levels are influenced by liquid intake from water, other liquids, and fruits and vegetables with high water content. Half of the world’s population doesn’t meet recommendations for daily water intake, according to research cited by the study’s authors. U.S. adults drink about 5 cups of water a day.
The National Academy of Medicine recommends a daily fluid intake of 91 ounces for women and 125 ounces for men. This guideline includes all fluids (including coffee, yay!) and water-rich foods such as fruits, vegetables and soups. Given an average fluids-to-foods intake ratio of 80:20, that means 9 cups for women and 12.5 cups for men.
Some healthcare professionals maintain that people’s normal drinking behavior provides adequate hydration. Others, like the National Council on Aging, maintain that a lack of thirst doesn’t mean someone is properly hydrated. Yet, a person can drink too much water and cause hyponatremia (water toxicity), which can be fatal in some cases.
Ultimately, how much water you need to drink each day to stay hydrated depends on your particular needs. Factors such as age, activity level, diet, health, medications and climate should be taken into consideration. One guideline recommends drinking the number of ounces that is equivalent to one-third of our body weight. For example, if you weigh 150 pounds, you should drink 50 ounces of water or other fluids.
Final Words
Just as proper nutrition and regular exercise are considered part of a healthy lifestyle, there is growing evidence that consistent optimal hydration may improve health and slow down the aging process.
Check with your doctor before increasing or decreasing your fluid intake, especially if you suffer from a chronic disease and/or regularly take medications.
