We have idealized this drink. Do we want to do a detox treatment after a weekend full of jarana? Tea. Are we trying to lose weight? Tea. Do we want to warm up on a cold day? Tea, of course. Monday first thing in the morning, asleep like us alone and wanting to wake up? If we hate coffee, the answer is, of course, tea. The media have taken care to put this drink on a pedestal. Not surprisingly, it is packed with natural antioxidants and poses no health risk, at least not if taken in moderate amounts.
But we know that there are people for everything and it won’t take us long to think of a couple of acquaintances who consume tea as real addicts. Of course, as we have said, they do it with good intentions since it is ‘healthy’, but excessive consumption of tea has several dangerous side effects that can put our health at risk. They’re next:
Less iron absorption
Have we ever noticed that drinking tea ‘dried‘ in some way the tongue and mouth in general? It is a relatively similar sensation to drinking red wine (although with a completely different taste). This is due to the presence of tannins, metabolites present in certain plants that have the ability to bind to a multitude of organic molecules, ‘blocking’ the interaction they may have with other different ones. Tannins are mainly known because they are the chemicals used to tan skins like leather. In fact, ‘tanning’ in English is called ‘tanning‘, which is a direct derivative of tannin.
As a number of Kansas State University researchers explain in one study, “iron deficiency remains a global health problem, and certain anti-nutrients, such as tannins, are often regarded as ‘contributors’ to this problem. According to the researchers, these molecules can bind to the iron molecules present in certain foods, making it unusable and unabsorbable by our digestive tract.
In addition, the researchers specify that the amount of tannins in the tea depends on the type of leaf and how it has been prepared. With all this in mind, they recommend drinking 3 or fewer cups of tea (which would add up to about 710 ml) a day. That, of course, is a recommendation for the general population, but those already suffering from a lack of this vital metal should further limit (or even suppress) their tea consumption.
Anxiety, stress and lack of rest
It’s no secret that tea contains caffeine. Although we often hear that no, that what this drink contains is theine, in reality it is exactly the same molecule. As a study by the Indian Institute of Dental Sciences explains, black is the variety with the most caffeine, followed by white, red and green.
It is true that, anyway, the concentration of this molecule in the leaf of Camellia sinensis (the scientific name of this plant) is relatively low. In fact, according to the study mentioned in the previous paragraph, one cup, on average, contains between 11 and 61 mg of caffeine. Researchers at the University of Buffalo believe that daily doses of this stimulant below 200 mg have no really noticeable, or at least negative, effects. However, they are aware that there are certain people with hypersensitivity to caffeine. In these cases, the most unpleasant effects of this molecule can occur: anxiety, inability to fall asleep, inability to stay asleep or spend the night ‘pull’, stress and tiredness.
It’s a side effect of caffeine. It’s capable of causing acid reflux. It is believed, or at least by researchers at Mihidol University in Thailand, that caffeine has the curious ability to relax the sphincter (valve) that separates and shuts off the passage from the esophagus to the stomach, allowing stomach contents (and the hydrochloric acid in charge of processing it) to pass into the upper duct.
This not only causes a more than uncomfortable reaction, but also poses a long-term health risk, because acids are capable of causing lesions in the esophagus, since this duct is not prepared for contact with acid.
Headache and dizziness
Other side effects of caffeine. Curiously, it’s not exactly the effect of this molecule, but the way we consume it. It’s continued use that can cause these symptoms, but, as R. E. Shapiro of the University of Vermont School of Medicine explains in a study, intermittent use can have exactly the opposite effect, relieving these symptoms.
Another study by W. J. Schonewille of Utrecht University suggests that consumption of just 100 mg of caffeine (which would mean less than 2 cups of black tea) may contribute to a recurrent daily headache, but this figure can vary greatly with each individual’s tolerance of the molecule.
On the other hand, a study by researcher C. Willson explains that large amounts of caffeine (between 400 and 500 mg, the equivalent of 1.4 – 1.8 l of tea) can cause dizziness. Of course the researcher clarifies that, again, “this figure can vary depending on the tolerance to caffeine of each individual.
In any case, tea is still very good for our health, but its consumption implies ‘getting to know each other’ and being able to relate unpleasant symptoms that, at first glance, would never occur to us that were the fault of this popular drink.