How Does Caffeine Work and the Effects of Caffeine

Difficulty Index ★★★☆☆

Ava Kim '26

Coffee is one of the most widely consumed beverages in the world, often because individuals need caffeine to feel less tired or prevent them from sleeping during the day. Caffeines are extremely effective in making you feel focused and refreshed, while they can cause you to have difficulty sleeping or feel anxious. So what is caffeine, how does it work, and how does it specifically affect our body?

Caffeine is a stimulant that increases the energy, alertness, and brain activity in the brain and nervous systems. They are commonly in coffee, tea, cacao plants, or guarana berries and are often found in medication, energy drinks, gums, etc. When caffeine enters the body, it takes 45 minutes, and an average of 30 minutes to get absorbed into your body which directly depends on the pH, and its efficacy can be extended by food intake. They are very quickly distributed throughout body water by immediately traveling across the cell membranes, including the brain. They are divided into three molecules: theophylline, theobromine, and paraxanthine. Each of these has different properties and each has its unique properties that affect our bodies. Theophylline increases concentration and heart rate, Theobromine increases circulation of nutrients and oxygen to the brain, and Paraxanthine maximizes the heart rate and increases athletic performance. The caffeines’ primary apparatus for triggering activity is to restrain those phosphodiesterase and block the adenosine receptors. Adenosine is a neurotransmitter that contributes to many different functions such as the regulation of vasodilation, neurotransmitter release, and vasoconstriction. Primarily, adenosine causes sleep activation in our brain and caffeine prevents us from sleeping. When adenosine is blocked, other neurotransmitters such as dopamine, gamma-aminobutyric acid, and norepinephrine are also affected. Therefore, this is how caffeine affects human attentiveness and emotion. Caffeine has a half-life of 6 hours meaning they are eliminated from your body system until 6 hours.

How do they affect our body once absorbed?

Caffeine has numerous functions that affect our bodies in different ways. To the central nervous systems, the stimulating effects can cause alertness immediately, so it will allow you to feel less tired or more awake. They are known to be ingredients in medications to manage headaches, migraines, or drowsiness. However, too much caffeine can cause headaches because our blood vessels adapt to caffeine and once they are stopped, it causes a headache. In digestive and excretory systems, the amount of acids in your stomach is increased due to Caffeine. Therefore, it can cause stomach upset or heartburn. You also might have an increase in urination after having caffeine because the remaining caffeine is processed in the living and exists through the urine. For circulatory and respiratory systems, caffeine increases your blood pressure in a short amount of time. This would either cause to temporarily block those hormones that widen arteries or increase the adrenaline. If you have irregular heartbeats, caffeine may increase your blood pressure. For reproductive systems, caffeine travels from the bloodstream to the placenta. Since caffeine is a stimulant, absorption of too much caffeine can cause an increased risk of miscarriage. Therefore, during pregnancy, controlling the amount of caffeine you take in is essential. Lastly, in the skeletal and muscular systems, large amounts of caffeine can be involved in the metabolism of calcium and its absorption. Therefore, this can generate osteoporosis which is bone thinning. Caffeine can also cause your muscles to tremble. As a result, caffeine can benefit you from changing your body systems but it is always important to know how much caffeine you absorb each day because it can also harm your health. 

Works Cited

Boudreau, Sarah. "How Does Caffeine Affect the Body?" Visible Body, 2 Sept. 2022, www.visiblebody.com/blog/how-does-caffeine-affect-the-body. Accessed 6 Oct. 2024.

"Caffeine." Better Health Channel, 8 Feb. 2022, www.betterhealth.vic.gov.au/health/healthyliving/caffeine#:~:text=Caffeine%20is%20a%20stimulant%2C%20which,you%20feel%20refreshed%20and%20focused. Accessed 6 Oct. 2024.

Cherney, Kristeen. "The Effects of Caffeine on Your Body." Edited by Katherine Marengo. Healthline, 7 Nov. 2018, www.healthline.com/health/caffeine-effects-on-body. Accessed 6 Oct. 2024.

Petre, Alina. "What Is Caffeine, and Is It Good or Bad for Health?" Healthline, 18 May 2023, www.healthline.com/nutrition/what-is-caffeine. Accessed 6 Oct. 2024.

Weaver's Coffee and Tea. 29 Sept. 2023, weaverscoffee.com/blogs/blog/how-caffeine-in-coffee-works?srsltid=AfmBOoqDichvMtEDIdCzFMaX3I2r2VBCeKUTlaSYvg1IdBySz39pkhy4. Accessed 6 Oct. 2024.