Coffee does count toward daily hydration, according to the article, despite its reputation as a dehydrating drink. Experts say that for most people, the water in coffee more than offsets caffeine’s mild diuretic effect, so a morning cup contributes to the body’s fluid balance as well as alertness.
Dr. Raj Dasgupta, a physician and internal medicine specialist, said, “Caffeine does have a mild diuretic effect, but the amount of water in coffee usually compensates for it, especially in people who drink coffee regularly.” Dietitian Alex Larson agreed, while warning that very large amounts of caffeine can increase fluid loss in some people.
That threshold is typically around 400 milligrams of caffeine a day or more, roughly four cups of coffee and up. The U.S. Food and Drug Administration says up to 400 milligrams per day is generally safe for most adults and is not usually linked to negative health effects. Pregnant women, people sensitive to caffeine, and those with sleep problems, anxiety, or heart rhythm disorders may need to limit intake much more.
The article notes that tea, green tea, and even soft drinks can also contribute to daily fluid intake, but not all beverages are equally healthy. Sugary drinks, energy drinks, and highly processed beverages hydrate but are not recommended for everyday use, while water and unsweetened tea remain the best choices.
To keep hydration balanced, experts advise not relying on coffee alone. One simple recommendation is to drink a glass of water with each caffeinated drink, especially in hot weather or around exercise. Dasgupta also recommends starting the day with water before coffee, saying that “starting the morning with a glass of water can make a significant difference in hydration throughout the day.”
