Early in the morning, a cup of coffee is transformative, and at the end of the day, a cup of tea acts as a source of comfort, easing the tired mind. Tea also happens to be a go-to remedy during cold-season when other forms of medication are unable to soothe aching throats. Coffee, though it is not the preferred drink of the sick person, has qualities that are similar to tea. Like tea, it is also capable of reducing severe swelling: they are both anti-inflammatories. With these multiple uses, it is no wonder that tea and coffee are age-old drinks that continue to be medically and culturally valued. Yet, what is the science behind their anti-inflammatory properties?
The Chemical Catechol. Image by Wikimedia Commons.
This question can only be answered by analyzing the chemical nature of tea. Generally, all forms of tea are derived from the same plant: the Camilla Sinensis. The only reason we have varying types of tea is because the plant is processed differently, depending on the flavor desired. For example, black tea tends to be a highly oxidized version of the plant, resulting in the chemical compound Theaflavin (which is currently under study as an anti-cancer agent). Within the plant itself is the catechin metabolite, which is chemically linked to the flavonoid family. Chemically speaking, the catechin molecule resembles catechols, which coincidentally tend to be the central part of chemicals within the human body: the catecholamines. The catecholamines include adrenaline, noradrenaline and dopamine, hormones that are released from the adrenal medulla during the fight or flight response. Therefore, when tea is consumed, the catechins in the tea tend to mirror the effect of the catechols in hormones such as adrenaline, leading to a mild sympathetic response.
How does the fight or flight response relate to the healing process? When the body enters the fight or flight response, blood flow is directed to the body’s larger musculature and away from the peripheral blood vessels, such as those lining organs and skin. As a result, the peripheral blood vessels constrict. This is the opposite of inflammation, a process whereby blood is directed to the site of the wound or infection and the vessels are dilated (hence the swelling that results after an injury or when one is ill). By consuming tea and enabling the fight or flight response, these vessels shrink, and the opposite of inflammation occurs: anti-inflammation.
In fact, it is for this reason that green tea bags are often dampened and applied to small cuts or pimples, reducing the blood flow to these sites and allowing for less swelling. The message that catechins employ is much more powerful than the natural immune response that releases histamines, the initial messengers in the inflammatory cascade that trigger the eventual swelling of the site. This is also seen in other catechol-derivative containing products such as Witch Hazel, which is a known first aid substance that is effective in treating wounds such as insect or snake bites (and also holds antiseptic qualities which allow for detoxification to occur).
Similar to tea, coffee also has anti-inflammatory effects, yet its effects are a result of the stimulant caffeine, rather than the metabolite catechol. Caffeine is capable of binding to adenosine receptors within our bodies, which are receptors in the central nervous system. These receptors are essential in the sleep cycle, binding adenosine and triggering a sleep response when levels of adenosine are high. By displacing the adenosine and blocking it from binding again, the caffeine is able to override the sleep response, for low adenosine levels signal little sleepiness. Caffeine also goes on to affect our peripheral vasculature, redirecting our blood flow to our big musculature and relaxing the vessels lining the skin, forebrain, and gonads. For this reason, after a cup of coffee, one may realize their hands getting slightly colder and a greater inability to concentrate (with blood flow moving away from the forebrain). Yet, it is for this reason that coffee acts as tea does: constricting the vessels on the periphery and limiting dilation, an anti-inflammatory response.
It is important to note that though anti-inflammation is useful, it tends to be a double-edged sword of sorts, for if one curtails inflammation, they are also inhibiting the fight against foreign agents within the body. If inflammation is ceased at any stage, the natural immune response is unable to rid the body completely of the foreign material. For this reason, anti-inflammatories should be paired with anti-infectious agents such as antibiotics or Witch Hazel, which allow for the removal of bacteria or viral particles respectively.
Though tea and coffee have anti-inflammatory qualities, they are not the first mode of action in the case of a serious injury or wound. Yet, if a small cut is stubbornly bleeding or one’s nasal passages are swollen, it then may be best to apply a tea bag on the site of inflammation or drink a cup of coffee and see what unfolds. These drinks and their versatility is a testament to the remarkable ability of chemicals in the natural world to mimic the chemicals that comprise the human body. It is these similarities that make them both enjoyable and beneficial, and perhaps a contributing factor in their hold on us; after all, who can go a day without either drink?
By Zahraa Saab
Please note that opinions expressed are the author’s own. They do not necessarily reflect the views and values of The Blank Page.
