The Truth About Caffeine: How Coffee Really Affects Our Bodies

Coffee. Go juice. Liquid gold. The one with all the psychoactive properties. Once used by Sufi mystics as a concentration aid during religious rituals, today it is one of the most common beverages on the planet: we drink around 2 billion cups a day.

It is also one of the most popular and popular drinks. One particularly sought-after blend, Black Ivory, which is produced by encouraging elephants to digest Arabica berries, sells for over £2,000 a kilogram, while coffee-making championships attract thousands of spectators. p>

But what does it do for you? You may have a vague idea that caffeine wakes you up, disrupts your sleep, and can aid athletic performance, but do you know how much you can safely drink? Considering that a typical americano contains over 100 biologically active ingredients other than caffeine, what do you know about the drug you're consuming two or three times a day? What happens to your body when you take a double espresso in the morning?

How fast does it work?

Effects can start even before you take a sip. According to a 2019 study of 80 young people aged 18 to 22, simply inhaling the smell of coffee can improve memory and boost alertness. Another study, from 2018, found that subjects performed better on analytical reasoning tests after a whiff of the good stuff. That said, researchers from the 2018 study suggested that the effect likely had a placebo element, with the expectation of improved performance found to be at least partly responsible.

What about when you drink it? "It's possible that the use of any supplement could have a placebo effect," says Dr. Mike T Nelson, a researcher and performance scientist who recently co-authored the International Society of Sports Nutrition's position on coffee. “Many researchers use randomized, double-blind, placebo-controlled trials to try to find this out. And if you look at some of the higher dose caffeine studies and when compared to a placebo, we still see a performance enhancing effect of caffeine.

This is why the effects really kick in sometime after you start drinking. While a 2008 study found that the effects of a cup of coffee can occur just 10 minutes after ingestion, it indicated that the peak blood caffeine concentration occurred after 45 minutes.

>How does coffee wake you up?

Caffeine acts as a central nervous system stimulant - making you more alert and focused, but potentially also more irritable and anxious. It's all tied to your body's adenosine receptors, which help regulate your heart rate, blood flow, and sleep-wake cycles. When adenosine - an organic compound found naturally in your body - binds to these receptors, it triggers physiological responses that result in decreased cellular activity, often promoting drowsiness and sleep.

Caffeine can trick your nerve cells into binding to them instead, preventing adenosine from doing its job. This promotes heightened alertness, while allowing stimulating neurotransmitters in the brain (like dopamine) to run wild. This makes it a mood booster for many people, but can also lead to anxiety after high doses. While your body adjusts to the effects of caffeine over time, different people may have very different responses to the same amount.

Can it really improve athletic performance?