What Tea Causes Dry Mouth? The Astringent Truth About Tannins and Your Brew

October 29, 2025 •

4 min read

According to scientific research, the uncomfortable dry or chalky sensation you feel after sipping some teas is caused by natural compounds called tannins binding to proteins in your saliva. Understanding what tea causes dry mouth is key to enjoying your cup without the unpleasant side effects.

Quick Summary

Dry mouth from tea is primarily caused by tannins, which bind to salivary proteins and reduce oral lubrication. Black tea has higher tannin levels and is often the main culprit, though brewing methods for any tea type can intensify this effect. Hydrating alternatives exist and proper brewing can minimize the astringent feel.

Key Points

Tannins are the culprit: The dry mouth sensation is caused by tannins in tea binding to and reducing the lubricating properties of saliva.
Black tea is highest in tannins: Generally, black tea contains the highest concentration of tannins, especially when over-steeped, and is the most likely to cause a dry mouth.
Brewing technique matters: You can minimize the drying effect by controlling the water temperature and steeping time, particularly for green and black teas.
Caffeine adds to dryness: High caffeine intake can cause a mild diuretic effect, potentially contributing to a feeling of dryness, though it's not the main reason for the astringent sensation.
Herbal teas are hydrating alternatives: Caffeine-free herbal options like ginger, peppermint, and chamomile can actually help stimulate saliva flow and provide soothing hydration.
Timing your tea matters: To avoid hindering nutrient absorption, especially iron, drink tannin-rich teas an hour or two away from meals.

The Science Behind Astringency: Tannins Explained

When you experience a dry, puckering, or rough feeling in your mouth after drinking tea, you are encountering a phenomenon known as astringency. This is not a sign of dehydration but rather a chemical reaction involving tannins, a type of polyphenol found naturally in tea leaves and other plant-based foods. When brewed, these heat-stable compounds bind with and coagulate the lubricating proteins present in your saliva, temporarily reducing its effectiveness and causing that unmistakable dry sensation. The specific concentration of tannins and how they are extracted determine the intensity of this effect.

Caffeine's Role in Oral Hydration

While tannins are the primary cause of the astringent feeling, caffeine plays a secondary role that can contribute to a sensation of dryness. Caffeine is a mild diuretic, meaning it increases urine production. For most tea drinkers, the volume of water in a normal cup of tea is enough to counteract the diuretic effect of the caffeine, so moderate consumption won't lead to dehydration. However, consuming large quantities of highly caffeinated tea (over 8 cups a day) can have a mild dehydrating effect, which could worsen a dry mouth sensation. For those who are already sensitive or prone to dryness, opting for lower-caffeine or caffeine-free herbal teas is a safer choice.

The Worst Offenders: Teas High in Tannins

Black tea: This is generally the most astringent and most likely tea to cause a dry mouth due to its high tannin content. The oxidation process used to create black tea amplifies these compounds. Over-steeping black tea will further increase the tannin extraction, making the effect even more pronounced.

Pu-erh tea: This aged, fermented Chinese tea is known for its earthy flavour but can also cause a very dry mouth sensation, sometimes referred to as 'locked throat'. This is often due to improper processing or storage, which can result in excessively high tannin levels.

Some green teas: While generally lower in tannins than black tea, certain green teas, particularly when brewed with water that is too hot or steeped for too long, can become unpleasantly astringent and drying.

Brewing Techniques to Prevent Dry Mouth

Adjusting your brewing method is one of the most effective ways to mitigate the drying effect of tannins.

Control temperature: For green and white teas, use cooler water (70-85°C) instead of boiling water to avoid over-extracting tannins. For black tea, a slightly lower temperature than boiling can also help.
Watch the clock: Steep tea for the recommended time to prevent the release of too many tannins. For green tea, this might be as little as 30-50 seconds.
Add modifiers: Adding a splash of milk or a squeeze of lemon juice can bind to some of the tannins and neutralize the astringent effect.
Use better quality tea: Lower-quality teas often contain broken leaves and stems, which can release higher concentrations of tannins and other compounds that lead to a harsher mouthfeel.

Hydrating Herbal Alternatives

For those who prefer to avoid the astringency altogether, several herbal teas offer a hydrating and flavourful experience without the drying effects.

Ginger tea: Known for its ability to stimulate saliva flow, ginger tea is a great option for promoting oral moisture.
Chamomile tea: This is a soothing, caffeine-free herbal tea that is gentle on the mouth and can aid in hydration.
Peppermint tea: Peppermint is another caffeine-free option that stimulates saliva production and offers a refreshing flavour.
Rooibos tea: This herbal tea from South Africa is naturally caffeine-free and low in tannins, making it a smooth, hydrating choice.
Slippery elm tea: This herbal remedy creates a protective, lubricating film in the mouth, providing direct relief from dryness.

Nutrition and Dietary Context

It's important to remember that the dry mouth caused by tea's tannins is not a sign of poor hydration, but it does highlight the beverage's impact on oral sensation and potentially, nutrient absorption. Tannins can interfere with the absorption of certain nutrients, most notably iron. This is particularly relevant for individuals with or at risk of iron deficiency anemia. To mitigate this, consider these tips:

Timing: Drink tannin-rich teas like black tea at least an hour or two away from meals, especially those containing iron-rich foods.
Pairing: Combine tannin-rich teas with foods high in Vitamin C, as this vitamin helps counteract the negative effects of tannins on iron absorption.
Variety: Incorporate a variety of beverages into your daily routine, including plenty of plain water, to ensure consistent and adequate hydration.

Comparison Table: Tea Types and Dry Mouth Potential


Feature	Black Tea	Green Tea	Herbal Tea (e.g., Chamomile, Peppermint)
Tannin Content	High	Low to Medium (depends on brewing)	Low to None
Caffeine Level	High	Medium	None
Drying Potential	High (due to tannins and caffeine)	Medium (if brewed incorrectly)	Low to None
Brewing Recommendations	Avoid over-steeping; use slightly cooler water.	Use cooler water (70-85°C); steep briefly.	Generally, brew according to package directions; no issues with tannins.
Best For Dry Mouth?	No	Moderate, if brewed properly.	Yes, a good hydrating alternative.

Conclusion: Enjoying Your Tea Without the Dryness

In the grand scheme of a balanced nutrition diet, understanding the nuances of how beverages affect your body is crucial. The question of what tea causes dry mouth is answered by identifying high-tannin teas, especially when brewed with high heat and long steep times. The resulting astringency is a flavour sensation, not a reflection of overall hydration levels. By adopting mindful brewing techniques, like controlling water temperature and steep time, you can significantly reduce the drying effect. For those with sensitive palates or specific nutritional concerns, embracing the wide variety of hydrating, low-tannin herbal teas offers a delicious and soothing alternative. Making these simple adjustments allows you to enjoy the rich flavours and potential health benefits of tea without the discomfort of a dry mouth.

Authoritative Source

Everyday Health - Tannin Levels in Teas: Benefits, Risks, and Best Choices. https://www.everydayhealth.com/beverages/tannin-levels-in-teas/

Frequently Asked Questions

Green tea contains fewer tannins than black tea, but it can still cause a dry mouth if you brew it with water that is too hot or steep it for too long. Using a lower temperature and shorter steeping time minimizes this effect.

Caffeine is a mild diuretic that can cause a slight increase in urination, potentially contributing to a feeling of dryness, but it is not the primary cause of the astringent sensation. The amount in a typical cup of tea is usually too low to cause significant dehydration.

To prevent dry mouth, try brewing your tea with cooler water, shortening the steep time, or adding a splash of milk or lemon. Alternatively, switch to a low-tannin herbal tea like chamomile or ginger.

No, not all teas are drying. The astringent effect comes from tannins, which are most prevalent in black and some green teas. Herbal infusions like peppermint, ginger, and rooibos are generally caffeine and tannin-free, making them non-drying and hydrating.

The dry sensation from tannins is a temporary chemical reaction where tannins bind with salivary proteins, creating a lack of oral lubrication. True dehydration occurs when your body lacks sufficient fluid overall. You can be hydrated and still experience the tannin-induced dry mouth feeling.

Yes, adding milk to your tea can help neutralize the astringent effect. The proteins in milk bind to the tannins, preventing them from interacting with your salivary proteins and reducing the dry, puckering sensation.

Yes, tannins can interfere with the absorption of certain nutrients, most notably iron. To minimize this, it's recommended to drink tannin-rich teas at least an hour or two away from mealtimes, especially if you are watching your iron intake.