Nutrition

Does Tea Dehydrate You? Here Are Reasons Why Or Why Not 2025

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Tea lovers worldwide pour a hot or cold cup of this popular beverage multiple times daily — but is this healthy hydration?

Globally it comes in second choice to water, but does tea dehydrate you? Some hypothesize that teas can dehydrate you since they contain caffeine and theobromine, which can increase urine output.

Many types of tea, like black, white, green, or oolong, are all made from the Camellia Sinensis[1] tea plant, which is known to contain approximately 6% caffeine. Teas vary with different colors, aromas, and flavors, but all are rich in catechins, caffeine, and L-theanine.

Different teas can affect your body differently, and some can be beneficial, like improving sleep, cholesterol levels, and organ function, thanks to the medicinal value of the compounds found in tea leaves. Catechins, for example, are anti-inflammatory and have been used to increase human longevity. In addition, L-theanine may improve alertness and prevent caffeine jitters.

Does tea make you dehydrated, though? Does it provide any other health benefits? This article will answer these questions and compare different types of tea and their potential for dehydration.

Does Tea Cause Dehydration?

Originating from China, tea comes from plant leaves that can be dried, roasted, and brewed in boiled water. Tea is mostly water, and the water is hydrating.

Tea is very unlikely to cause dehydration, but because there are properties of tea that can increase your chances of losing water in various ways, we’ll take a look at what dehydration is, what stimulants in tea do to the human body, and how they create this fear of excessive water loss.

Key Takeaways

In 2020, global tea consumption accounted for[2] 6.3 billion kilograms and is expected to reach 7.4 billion kg by 2025.

  • Tea is the most consumed drink in the world after water.
  • There are several stimulants in tea that can encourage fluid loss, but normal tea consumption is more hydrating than not.
  • Tea contains, on average, 30-40 milligrams of caffeine per cup, while coffee contains around 95.
  • Caffeine is safe for consumption up to 400 milligrams per day for adults and 200 milligrams if you’re pregnant.
  • Drinking tea may help fight cancer and benefit your brain, heart, and metabolism.

What Is Dehydration?

Dehydration is the imbalance in your body when it does not have enough fluids to function properly. How much water you should drink per day to remain hydrated varies for each individual.

As a rule of thumb, you should drink when you’re thirsty and monitor yourself for signs of dehydration,[3] like the following:

  • Dry mouth, eyes, and lips.
  • Dark yellow or brown pee.
  • Urinating less than three times a day.
  • Headache.
  • Dizziness.
  • Confusion.
  • Fatigue.
  • Dry skin.

What Tea Stimulants May Affect Hydration?

Tea is commonly thought to be dehydrating because of its organic compounds that can increase urine output. All teas are different, but some teas contain more or less of:

How Can These Stimulants Dehydrate Someone?

Teas that contain caffeine and theobromine are generally believed to be dehydrating since they are mild diuretics.[5] That means it encourages fluid loss through an increase of sweating or urinating.

Many caffeinated drinks have such large quantities of the substance that they can cause an increase in body temperature, but it does not normally cause excessive fluid loss. The recommended daily limit for caffeine is 400 milligrams[6] per day for adults and 200 milligrams for pregnant women.

Everyone has a different tolerance level for caffeine, which can go up and down the more or less they consume caffeine. If a person is overly sensitive to caffeinated tea or drinks too much caffeine, they may eventually become dehydrated if they aren’t actively rehydrating properly.

What Does Science Say?

While there are no current scientific studies on the effects of tea on hydration, it is worth noting that research[7] on drinking coffee shows that moderate consumption does not affect your total body water with a significant diuretic effect. It would likely take large quantities of coffee to cause dehydration, so the potential for tea to cause this may be even less.

Coffee has around 95 milligrams[8] of caffeine per eight-ounce serving. A cup of tea contains less caffeine at around 30-50[9] milligrams per cup.

So, does drinking tea usually dehydrate you? Ultimately, with moderate tea consumption, you gain more hydration than you lose, but some teas can have more potential than others to cause a diuretic effect.

Now if you are already on a medication or herb that acts as a diuretic, you should monitor your input and output closely to ensure your hydration levels are adequate.

Different Teas May Have Different Effects

The effects can vary depending on the level of tea’s diuretic compounds. Let’s look at the likelihood of dehydration in different types of teas.

Does White, Green, Or Black Tea Dehydrate You?

Does White, Green, Or Black Tea Dehydrate You?

Since these teas contain a modest amount of caffeine, it would take a high serving amount during a short period of time to stimulate enough urine production to affect your hydration levels. However, if you are not new to caffeine or highly sensitive to it, the amount of fluid in tea is generally enough to balance the diuretic effects of the caffeine.

Does Sweet Iced Tea Dehydrate You?

Does Sweet Iced Tea Dehydrate You?

Sweet iced tea is one of the most popular forms of tea and is usually made from black tea leaves. Some sweet teas add too much sugar, which can encourage gut inflammation and increases your body’s need for water since it requires more water to process the sugar, so if rehydration is not occurring, the sugar may be the culprit.

Does Herbal Tea Dehydrate You?

Does Herbal Tea Dehydrate You?

Herbal teas do not come from the tea plant. You may see herbal teas made from a variety of ingredients, including dried herbs, flowers, fruit, seeds, and spices. They can also contain leaves and roots from various plants, like dandelion and lemon balm.

Since herbal teas, in general, are decaffeinated tea, the chance of them helping you to stay hydrated increases.

Health Benefits Of Tea Beyond Hydration

The nutritional value and benefits[10] of drinking tea outweigh the risk of dehydration. Here are a few of the ways tea can benefit your overall health.

Brain

Studies show[11] that those with a consistent tea-drinking habit had better memory scores and less risk of cognitive decline. Tea, as mentioned earlier, also contains L-theanine,[12] an amino acid that helps reduce stress and improve your ability to focus.

Heart

Tea contains heart-healthy antioxidants, and the same theobromine that can cause a mild diuretic effect can help widen blood vessels for better blood flow and help lower blood pressure. Consuming tea can also help lower cholesterol[13] levels. Newer studies[14] on black tea show that drinking at least two cups daily lowers the risk of heart disease and stroke death.

Energy

Tea makes some people more productive. For example, scientific studies show that drinking one to two cups of coffee or more than one cup of tea consistently daily increases physical activity[15] by 17% and 13-26%, respectively. Another study shows that four cups of green tea daily may also increase your metabolism and result in weight loss[16] and a decreased waist circumference.

A moderate caffeine content can boost energy, but consuming too much can result in unwanted side effects, like anxiety, jitters, and energy crashes.

Cancer Prevention

Several studies show that the health benefits of drinking green tea include preventing the growth of cancer cells and causing cancer cell death.

The Bottom Line

While some tea contains stimulants that can have a mild diuretic effect, this beverage is mostly water and is more likely to help you restore liquids to your body than dehydrate you.

You won’t lose more water than you take in with a mindful and moderate consumption of caffeinated beverages. Keeping an eye on your hydration status and drinking as much fluid as you need when you’re thirsty can help you prevent dehydration.

Drinking hot or cold tea can provide you with several health benefits, including boosting your energy, brain, and heart health. Since different types of teas have various effects, smells, and tastes, experimenting with different ones can help you decide which you prefer.

Stick to 400 mg of caffeine or less per day. If you are experiencing symptoms of dehydration, increase your water intake with added electrolyte-balancing ingredients. If symptoms of dehydration persist, you may wish to contact your healthcare provider.

+ 16 Sources

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  2. Statista. (2022). Global: annual tea consumption 2012-2025 | Statista. [online] Available at: https://www.statista.com/statistics/940102/global-tea-consumption/
  3. Mayo Clinic. (2021). Dehydration – Symptoms and causes. [online] Available at: https://www.mayoclinic.org/diseases-conditions/dehydration/symptoms-causes/syc-20354086
  4. Pimentel, G.D., Micheletti, T.O. and Nehlig, A. (2014). Coffee Intake and Obesity. Nutrition in the Prevention and Treatment of Abdominal Obesity, [online] pp.245–259. doi:https://doi.org/10.1016/b978-0-12-407869-7.00024-6.
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  8. Usda.gov. (2023). FoodData Central. [online] Available at: https://fdc.nal.usda.gov/fdc-app.html#/food-details/171890/nutrients
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