Caffeine is widely consumed. The age average of the most active consumers of coffee is between 35 and 64 years old with also an average of 250mg/day (equivalent to 3 cups of brewed coffee). Caffeine is a natural compound found in some leaves and fruits. Some sources of caffeine are: coffee, black and green tea, cocoa, cola soft drinks, energy drinks, chocolate bars and energy bars.
People frequently suppose that an often drinker of caffeine will finally not be stimulated anymore by the pressor effect of this substance in his body. This fact is not true due to several researches and pharmacological findings in this field.
Caffeine is one of the most researched substance these days because of its wide diffusion in one’s body, and its many effects! But today we came to talk about its CARDIOVASCULAR EFFECT, taking into consideration both advantages and inconveniences of caffeine intake.
Before hitting the effects of caffeine on the cardiovascular system we need to clarify the importance of a structure in our blood vessels that is crucial for our study! It is called the “Endothelial Cells”. During this article you will probably read an “ECF” notation, speaking of the Endothelial Cells Function.
EC form the inner lining of blood vessels in our bodies. One of their role is to regulate and manage vascular tone (that somehow prevents thrombosis: a local coagulation or clotting of the blood in a part of the circulatory system). The function of EC inside the vessels is divided into two types:
- Normal function: this induces vasodilatation (or the dilatation of blood vessels, which decreases blood pressure)
- Abnormal function: that leads to vasoconstriction (including renin, angiotensin and endothelin I intervention). If overexpressed, it can cause on the long-term a hypertension.
Caffeine increases blood pressure
It is widely known in the science field that caffeine can block “adenosine receptors” (that play a major role in dilating arteries in order to increase blood flow during exercise). By blocking those receptors, caffeine activates the sympathetic tone and the renin secretion, a complex system that can increase blood pressure by constricting the vessels inside the body. This can lead to tachycardia if caffeine was consumed excessively, according to Higgins JP. in Endothelial function acutely worse after drinking energy beverage. International Journal of Cardiology. 2013
Caffeine can improve muscle contraction
After consuming a restricted amount of caffeine, we can see a direct increase of intracellular calcium that then stimulates nitric oxide production that diffuse into vascular smooth muscles and activate vasodilatation. As you can see, caffeine can have both vasoconstriction/vasodilatation effects on the vessels due to its wide diffusion and big bonding potential.
But most importantly, the release of Ca in cells directly upsurges the contractile force of skeletal muscles! Thus, better performances during workout and training sessions.
Caffeine can limit blood flow to many crucial parts in the body if consumed before/during/after exercise
According to Simone Cappelletti, Piacentino Daria, Gabriele Sani, and Mariarosaria Aromatario in “Caffeine: Cognitive and Physical Performance Enhancer or Psychoactive Drug?”, caffeine ingestion and exercise can lead to lower blood flow to important parts in the body: the brain for example.
Finally, we can say that we tackled the cardiovascular effect of caffeine on the human’s body. We concluded that it can have both positive/negative effects causing good or bad results. Findings and researches are still in the process trying to find and prove every effect of caffeine in the body. More work is being put into action. All I can say at the end, is that caffeine has not only a cardiovascular effect, but has many other positive effects related to cognition, alertness, performance, and energy!