Delaying aging by improved hydration.

Abstract

We would like to thank Dr. Ortiz for suggesting that chronic kidney disease (CKD) rather than hypohydration per se may underlie the increased risks of negative long-term health outcomes. We agree that it is a valid hypothesis for testing in future studies, including interventional trials that are needed for reaching definite conclusions. However, we believe that available information can already be put into practice. Thus, 142 mmol/l serum sodium threshold can be safely incorporated into clinical practice and everyday life. Based on this threshold, we recently proposed a strategy for making decisions about more comprehensive clinical evaluations, treatments, and fluid intake recommendations.1Dmitrieva N.I. Rosing D.R. Boehm M. Making decision about fluid intake: increase or not increase.Eur Heart J. 2022; 43: 4438-4439Crossref PubMed Scopus (0) Google Scholar Increasing water intake to the generally recommended levels is an integral part of the strategy. Applying this strategy would also facilitate early CKD diagnosis and initiation of treatment as Dr. Ortiz suggests. Concerns about dangers of fatal water intoxication are often overestimated. The maximal excretion rate of even minimally diseased kidneys is 0.8–1 L per hour, meaning that it can excrete up to 24 L of water a day2Sterns R.H. Disorders of plasma sodium--causes, consequences, and correction.N Engl J Med. 2015; 372: 55-65Crossref PubMed Scopus (321) Google Scholar that by far exceeds general recommendations. To prevent water intoxication, the rate of water gain should not exceed the maximal excretion rate that can be ensured through educational information.2Sterns R.H. Disorders of plasma sodium--causes, consequences, and correction.N Engl J Med. 2015; 372: 55-65Crossref PubMed Scopus (321) Google Scholar,3Rangan G.K. Dorani N. Zhang M.M. et al.Clinical characteristics and outcomes of hyponatraemia associated with oral water intake in adults: a systematic review.BMJ Open. 2021; 11e046539Crossref Scopus (3) Google Scholar Most cases of hyponatremia caused by excessive drinking occur when a large amount of water is consumed over a short period of time.3Rangan G.K. Dorani N. Zhang M.M. et al.Clinical characteristics and outcomes of hyponatraemia associated with oral water intake in adults: a systematic review.BMJ Open. 2021; 11e046539Crossref Scopus (3) Google Scholar Variability of individual water needs4Yamada Y. Zhang X. Henderson M.E.T. et al.Variation in human water turnover associated with environmental and lifestyle factors.Science. 2022; 378: 909-915Crossref PubMed Scopus (2) Google Scholar does not negate the importance of optimal hydration, but rather calls for the development of better methodology that would allow for the derivation of personalized fluid intake recommendations depending on environmental, demographic and lifestyle factors. Such methods could be useful, for example, to address the emerging epidemic of CKD of unknown origin among young agricultural and construction workers in hot, humid parts of the world. Exposure to heat and persistent dehydration is suspected to be the main causing factor.5Sorensen C. Garcia-Trabanino R. A new era of climate medicine - addressing heat-triggered renal disease.N Engl J Med. 2019; 381: 693-696Crossref PubMed Scopus (0) Google Scholar To summarize, although additional evidence is needed, why not try to improve hydration for the potential risk-free chance of longer disease-free life? All authors contributed to conceptualization and writing, read and approved the final version of the response letter. The authors declare that there is no conflict of interest. This work was supported by Intramural Research program of the National Heart, Lung, and Blood Institute (NHLBI): the National Institutes of Health grant ZIA-HL006077-10. The Atherosclerosis Risk in Communities (ARIC) study has been funded in whole or in part with federal funds from the NHLBI; the National Institutes of Health (NIH); and the Department of Health and Human Services, under contract numbers HHSN268201700001I, HHSN268201700002I, HHSN268201700003I, HHSN268201700005I, and HHSN268201700004I. Middle-age high normal serum sodium as a risk factor for accelerated biological aging, chronic diseases, and premature mortalityPeople 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. Full-Text PDF Open AccessNatremia after fasting 12 h, kidney disease and agingDmitrieva et al. report that middle-age high-normal natremia after 12-h fasting is a risk factor for accelerated biological aging and premature mortality.1 The manuscript was widely publicized in the lay press and, like others,2 interpreted as supporting a need for the general population to increase water intake (“The results suggest that proper hydration may slow down aging and prolong a disease-free life”, ”Researchers Find Super Simple Key to Healthy Aging:Good Hydration!”).3 However, excessive water intake may be lethal. Full-Text PDF Open Access