But tea also contains compounds called tannins—and there’s a lot of confusion about what that means for you and your health. You may have heard that tannins in tea are good for you, or you may have been told that it’s a better idea to stay away from them. So, what’s the deal? Because tannins are unpleasant, in theory, they’re produced as a defense mechanism to make the plant less palatable to keep the animal (or human) away. But when it comes to the tannins in tea, many people actually enjoy that characteristic taste. That’s probably why tea is one of the most common beverages in the world, second only to water. But black tea isn’t the only type of tea that contains tannins. All tea contains tannins, and different types of tea have varying levels. According to a January 2015 report in the Journal of Chemical and Pharmaceutical Research, black tea has the highest concentration, followed by oolong tea and then green tea. White tea, which is made from young tea leaves and is the least processed, has the lowest levels. Other sources of tannins include: In a 2018 review published in Current Medicinal Chemistry1, researchers wrote that another reason tannins are anti-inflammatory is that they can help balance the bacteria in your gut, shutting off inflammatory processes that come from your gastrointestinal tract. When combined with antibiotics, tannins also fight off antibiotic-resistant bacteria, like methicillin-resistant Staphylococcus aureus (MRSA), according to a 2015 report in Natural Product Communications2. What’s even more interesting is that in lab tests, tannins were found to be resistant to acid treatment, meaning that they can still work effectively in the harsh acidic environment of your stomach. Another tannin, called tannic acid, is resistant to medications and positively affects the immune system, so it also shows promise as an adjuvant therapy for cancer, according to an April 2020 review in Current Pharmacology Reports. Because of their neuroprotective effect, tannins have also been classified as a strong antidepressant, helping boost mood and overall well-being. That’s why, if you’re iron deficient, your doctor may have advised that you either don’t drink tea or only drink it in between meals rather than with an iron-rich meal. You can also reduce any potential negative effects by adding milk to your tea. The tannins bind with the milk protein, instead of the proteins in your gut, which prevents them from interfering with iron absorption. Eating vitamin-C-rich foods, like bell peppers, potatoes, cantaloupe, and/or oranges right before or after you drink your tea can also neutralize the tannins. According to a July 2014 report in the International Journal of Nutrition and Food Sciences, tannins can also block the digestion and absorption of proteins by either inhibiting the enzymes that you need to break them down or by making the protein biologically unavailable. And since tannins interfere with the proper functioning of enzymes, it can mess with your digestion as a whole. On that note, Nour Zibdeh, M.S., RDN, a functional and integrative dietitian and nutritionist, also points out that if you have a sensitivity to tannins, they can constipate you. Overconsumption of tannins can also cause stomach upset and nausea. However, researchers from a January 2017 study that was published in Current Developments in Nutrition6 wanted to make it clear that most studies that demonstrate a negative effect of tannins, especially when it comes to iron absorption, use amounts that you wouldn’t take in with average tea consumption. For example, one 5-ounce cup of tea typically contains around 25 to 80 mg of tannins. That means, even if you drank three cups of tea per day, you would be taking in only 75 to 240 mg of tannins. Most studies exceeded this amount, some using up to 1,000-mg doses of tannins. She has written twelve books and has had more than 2,000 articles published across various websites. Lindsay currently works full time as a freelance health writer. She truly believes that you can transform your life through food, proper mindset and shared experiences. That’s why it’s her goal to educate others, while also being open and vulnerable to create real connections with her clients and readers.