Mary Chris Jaklevic is a freelance health reporter and regular contributor to HealthNewsReview.org. She tweets as @mcjaklevic.
Human beings are naturally equipped with a system to regulate fluid intake. It’s thirst, and it works pretty well for the vast majority of us. Still, some news organizations are oddly compelled to remind us to drink more water. In the process, they often propagate ideas that aren’t supported by data.
Take this recent USA Today story entitled, “Why you should drink water first thing every day.” It quoted two registered dietitians, identified as representatives of the American Academy of Nutrition and Dietetics, who advised starting the day with two glasses of water to aid metabolism and digestion.
One of the dietitians acknowledged she hasn’t seen studies to support this, but says it does make “biochemical sense.” The other is asserted: “After being asleep all night, we wake up every day slightly dehydrated.”
Similarly, TIME sounded the dehydration alarm last year in a piece entitled “Why Hillary Clinton (And You) Should Be Drinking Water Regularly.” It blamed the candidate’s wobbly condition at a 9/11 ceremony on dehydration, a notion put forth by Clinton’s husband, just before her doctor revealed that Clinton had been diagnosed with pneumonia.
While the dehydration story may have been a smoke screen, TIME nevertheless rallied on to assert that Clinton is far from alone in her failure to drink enough fluids, citing another news outlet: “In 2013, CBS reported that some 75% of Americans may be functioning in a chronic state of dehydration, many mistaking the symptoms for other illnesses.” TIME advised: “Drink plenty of water!”
But the origin of the CBS data is sketchy at best. Its story, “Chronic Dehydration More Common Than You Think, doesn’t indicate where it found the 75 percent dehydration rate, attributing the statistic only to “new research.” In fact that number has been floating around the Internet for years and may have its roots in a self-published book by an Iranian-born doctor who believed drinking water could cure disease, according to Snopes,com, which investigates stories of questionable origin.
HealthNewsReview.org could find no evidence that most Americans exist in a state of unwitting desiccation. In fact the authoritative Institute of Medicine dispelled this long-standing dehydration myth in a 2004 report, stating: “The vast majority of healthy people adequately meet their daily hydration needs by letting thirst be their guide.”
The IOM, now called the National Academy of Medicine, said women who appear to be adequately hydrated consume an average of about 2.7 liters of water daily while men average 3.7 liters daily, and about 80 percent of that water comes from beverages of all kinds, with 20 percent from food. Its news release offered this reassurance:
“We don’t offer any rule of thumb based on how many glasses of water people should drink each day because our hydration needs can be met through a variety of sources in addition to drinking water,” said Lawrence Appel, chair of the panel that wrote the report and professor of medicine, epidemiology, and international health, Johns Hopkins University, Baltimore. “While drinking water is a frequent choice for hydration, people also get water from juice, milk, coffee, tea, soda, fruits, vegetables, and other foods and beverages as well. Moreover, we concluded that on a daily basis, people get adequate amounts of water from normal drinking behavior — consumption of beverages at meals and in other social situations — and by letting their thirst guide them.”
Yet even this definitive report didn’t put an end to the pro-water crusade. The CBS piece asserted that dehydration is a major problem: “Many people think they get plenty of fluids on a daily basis. What they don’t realize, however, is that they may be dehydrated which could lead to a slew of health issues including fatigue, joint pain and weight gain.”
While CBS and other news outlets draw a connection between drinking water and weight control in adults, a 2013 review concluded there aren’t good-quality studies to back that idea.
Myths abound, such as that eight glasses a day are required for good health, caffeinated beverages leach water from your system, and chugging plenty of H2O is good for your skin. Some news outlets such as the The Washington Post and the New York Times have done a good job busting these fables.
But the lore is difficult to quash, especially when it’s promoted by a booming beverage industry.
Overstating the risk of dehydration could prompt some people to drink things they shouldn’t, says HealthNewsReview.org contributor Yoni Freedhoff, MD, an assistant professor of family medicine at the University of Ottawa and medical director of its Bariatric Medical Institute.
Freedhoff sees no harm in having a glass of water here and there in the absence of thirst, but said “the main risk of sounding the dehydration alarm is that people will choose beverages other than water to rehydrate with many of them packing huge punches of free sugars.”
In extreme cases, gulping down too much liquid can be a hazard. MDAlert reported that over-consuming water appears to pose a greater threat to athletes than drinking too little. As the Chicago Tribune explained in a well-researched article about marathon runners, taking in too many fluids can lower blood sodium levels and cause cells to swell, a potentially lethal condition called hyponatremia.
Then there’s the needless worry. In his blog PainScience.com, writer Paul Ingraham says “just about everyone seems to feel slightly guilty” about not drinking enough water, and “many believe that they are probably ‘chronically dehydrated’ with unknown but ominous consequences.”
“The danger of media advice to drink more water is mostly minor: a trivial extra expense and an inconvenient number of trips to the toilet,” Ingraham told HealthNewsReview.org. “Still, it’s worth telling people that drinking a great deal of water is definitely not necessary.”
Now that’s advice we all can swallow.