Earlier this month, a team of researchers from the University of Birmingham in England released the results of a study on coffee and hydration. According to their work, coffee is just as hydrating as water.
This news is huge for someone like me. Ever since I can remember, I’ve been urged to drink more water, but I’m never really thirsty. Even after a long run, I often have to force myself to pour a glass of water.
Coffee on the other hand? Not a problem.
The study, published in the journal PLOS ONE, focused on 50 male subjects, all established coffee drinkers. For three days, half drank four cups of coffee each day, and the other half drank three cups of water. Then, after a 10-day hiatus and resuming their normal habits, they did it again, but swapped roles. Turns out, there was no difference in their levels of hydration.
Dehydration is serious business.
Sports dietitian Nancy Clark, MS, RD, explains that “as the body gets dehydrated, the heart has to work harder to pump blood through the vessels.”
The study’s lead researcher, Sophie Killer, points out that current ideas linking coffee and dehydration come from a 1928 study that is no longer relevant.
Speaking on the body’s ability to adapt to caffeine based on how much it takes in, Killer says that “your body becomes more able to regulate the fluid intake and is less susceptible to any increases in urine output that somebody who’s caffeine-naïve might experience.”
If you are anything like me, don’t ditch your Brita quite yet. An article in Nursing Times questioning some interpretations of the study might temper your enthusiasm: “Different findings could also be seen in women; in children; and perhaps most importantly, in people who are dehydrated or at risk of dehydration (for example with vomiting and diarrhea), or with certain health problems or taking medications that affect their fluid balance (such as heart or kidney problems).”
Now, if only coffee didn’t keep me up all night …
Do you think it’s essential to drink eight eight-ounce glasses of water every day? Tell us why—or why not?—in the comments or in a blog post.