Tea is remarkably the second most consumed beverage globally, just behind water. For most adults, drinking between two to four cups of tea daily provides various health benefits. In addition to being calorie-free, tea is rich in polyphenols, known for their antioxidant properties, and is beneficial for heart health. Furthermore, the presence of L-theanine, an amino acid found in tea, can help alleviate stress and anxiety. But does tea hydrate as effectively as plain water?
According to Dr. Carrie Ruxton, a dietitian with the Tea Advisory Panel, tea is indeed just as hydrating as water. She mentioned in an interview that they conducted a randomized controlled trial comparing tea and water consumption, with participants drinking either four or six servings daily. The results, published in the British Journal of Nutrition in 2011 (via Cambridge University Press), indicated no significant differences in blood or urine markers between those drinking tea and those drinking water.
While the study primarily involved participants in a controlled lab environment, Dr. Ruxton referred to earlier findings published in the European Journal of Applied Physiology (via Springer Nature Link) that suggest tea also promotes hydration in more strenuous situations, like during physical activities. She cited a study conducted at Everest base camp, where climbers consuming tea showed no difference in urine hydration markers compared to those drinking other non-caffeinated beverages. However, those who drank tea reported feeling significantly less fatigued.
Caffeine can affect hydration at high doses, so count your cups
However, it is worth noting that tea contains caffeine, a well-known stimulant found in all varieties of tea made from the Camellia sinensis plant, such as black, green, white, and oolong teas. Despite herbal teas being caffeine-free, black tea is notable for its higher caffeine levels, often exceeding 50 milligrams per cup. Dr. Carrie Ruxton highlighted that while black tea is relatively higher in caffeine when compared to coffee, which averages between 80-120 milligrams per serving, herbal teas are generally more effective at maintaining fluid balance. She cautioned that sodas, while hydrating, have high sugar levels, making them less healthy options than tea.
Caffeine acts as a mild diuretic, meaning that consuming high doses (over 500 milligrams, or more than five cups of caffeinated drinks) can result in dehydration. Dr. Ruxton explained that caffeine can affect hydration when consumed in large quantities or for those not accustomed to it, which is why it is not advisable for young children. She emphasized that tea is free from additives; its beneficial nutrients originate naturally from the tea plant. However, she noted that some mass-market brands may use artificial flavors and colors to enhance lower-quality tea leaves. Nonetheless, Dr. Ruxton affirmed that tea is an excellent choice for aiding daily fluid intake.
