Tannins are compounds present in tea, responsible for its distinct flavour, colour, odour and specific chemical properties. They belong to the category of polyphenols. Tannins are also present in foods and beverages like coffee, chocolate and wine in abundance, which accounts for their astringent and bitter flavours. Tannin levels in tea might vary depending upon the variety and tea with high tannin level is referred to as tannic. For example, black tea contains a high level of tannin but green, white and oolong tea has little or no tannin content. But the amount consumed will depend upon the duration for which it is steeped.
There are various myths attached with tannins that they are bad for us but the fact is that tannins have both up and downsides.
Tea offers two groups of tannins called theaflavins and thearubigins. They function as antioxidants and has the potential to neutralise free-floating radicals. They prevent our healthy cells and tissues from being damaged, in turn proving to be good for heart, brain, and skin.
Ellagitannin is another tannin found in tea which also exhibits powerful anti-inflammatory and antioxidant properties. In addition, some studies have linked ellagitannin benefitting gut bacteria.
Due to their antioxidant properties, tannins are also considered as anti-carcinogenic.
Even though tannins have certain health benefits, it has had side effects as well. The reason being, tannin has a unique property of easily binding with proteins and minerals.
Tannins affect the absorption of iron in our body. When any iron-containing food, especially plant-based food is consumed along with tannins, they bind with iron making it unavailable for absorption. Therefore, it is always recommended not to consume tea, coffee along with meals, especially during low iron levels, as it results in reduced iron absorption.
High levels of tannin consumption might affect our digestive system and lead to nausea. Due to this reason, some people feel uneasy after drinking tea or coffee, on an empty stomach.
They are usually considered anti-nutritional and affect protein digestibility.
To conclude, we can say that to get the benefits of tannins, consume them in moderation. Avoid taking them along with meals and enjoy your tea, coffee, etc. separately.