COFFEE × HYDRATION
COFFEE × HYDRATION
Coffee x Hydration
In conclusion, coffee counts as hydration.
During hot weather, we often hear that "coffee is not suitable for hydration" for some reason, but most of these claims lack evidence.
Conversely, there are multiple papers and studies suggesting that "coffee does provide hydration."
Based on evidence, I will explain the key points.
Can dehydration occur due to the diuretic effect of caffeine?
It is sometimes said that coffee is not suitable for hydration because it contains diuretic caffeine, which can lead to dehydration. This is a common argument against coffee for hydration, but studies have reported no significant difference between consuming only water and consuming caffeinated beverages (tracked across four groups).
It is scientifically established that while caffeine has a mild diuretic effect, it does not have a strong enough impact to cause dehydration.
That said, coffee contains many more chemical components than other beverages, and besides caffeine, it also has components that promote diuresis. Individual sensitivities to these vary, so it is true that many people find coffee makes them need to urinate more frequently.
However, even considering this, unless an abnormal amount is consumed excessively at once, it is highly unlikely that anyone would become dehydrated due to coffee components.
If consuming coffee were to cause dehydration, then roasters and baristas, who likely consume more coffee than anyone else, would be suffering from dehydration daily.
It goes without saying what the reality is.
Is coffee suitable for hydration?
One study found that both coffee intake and water intake (control) had no effect on body water (intervention study in coffee drinkers).
In other words, when comparing water and coffee for the purpose of hydration, the conclusion was that there was almost no difference.
After all, 98-99% of coffee is water. When you're not getting enough fluids, it's certainly better to drink coffee than nothing, and there's no problem drinking coffee in mid-summer.
Iced coffee on a hot day is exceptional. Enjoy it in moderation so you don't accidentally drink too much because it's delicious.
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-Caffeine has many effects on the body other than its diuretic action. While moderate amounts can have positive effects, excessive consumption can lead to adverse health effects. Therefore, it is important to be mindful of over-consuming caffeinated beverages, not just coffee.
-In normal daily life, coffee and tea adequately serve as hydration. However, during strenuous exercise or sports when a significant amount of fluid is lost, it is advisable to consume appropriate electrolyte-containing beverages, such as sports drinks, to quickly and adequately replenish necessary sodium, potassium, and other essential minerals along with water.
References (excerpt):
https://ilsijapan-org.prm-ssl.jp/ILSIJapan/BOOK/Newsletter/Water-1-NL_1006.pdf
https://www.jstage.jst.go.jp/article/kagakutoseibutsu/59/4/59_590401/_pdf
https://www.nestle.co.jp/sites/g/files/pydnoa331/files/asset-library/documents/nhw/interview7.pdf