Caffeine: The Silent Killer of Success
By Travis Bradberry, Ph.D.
September 08, 2014
Most people start drinking caffeine because it makes them feel more alert and improves their mood. Many studies suggest that caffeine actually improves cognitive task performance (memory, attention span, etc.)∈ the short-term. Unfortunately, these studies fail to consider the participants’ caffeine habits. New research from Johns Hopkins Medical School shows that performance increases due to caffeine intake is the result of caffeine drinkers experiencing a shortterm reversal of caffeine withdrawal.
By controlling for caffeine use ∈ study participants, John Hopkins researchers found that caffeine-related performance improvement is nonexistent without caffeine withdrawal. In essence, coming off caffeine reduces your cognitive performance and has a negative impact on your mood. The only way to get back to normal is to drink caffeine, and when you do drink it, you feel like it’s taking you to new heights. In reality, the caffeine is just taking your performance back to normal for a short period.
The Bad: Adrenaline: Drinking caffeine triggers the release of adrenaline. Adrenaline is the source of the “fight or flight” response, a survival mechanism that forces you to stand up and fight or run for the hills when faced with a threat. The fight-or-flight mechanism sidesteps rational thinking ∈ favor of a faster response. This is great when a bear is chasing you, but not so great when you’re responding to a curt email. When caffeine puts your brain and body into this hyper-aroused state, your emotions overrun your behavior. Irritability and anxiety are the most commonly seen emotional effects of caffeine, but caffeine enables all of your emotions to take charge. The negative effects of a caffeinegenerated adrenaline surge are not just behavioral. Researchers at Carnegie Mellon University found that large doses of caffeine raise blood pressure, stimulate the heart, and produce rapid shallow breathing.
The Ugly: Sleep: Caffeine has a six-hour half-life, which means it takes a full twenty-four hours to work its way out of your system. Have a∪ of coffee at eight a.m., and you’ll still have 25% of the caffeine ∈ your body at eight p.m. Anything you drink after noon will still be at 50% strength at bedtime. Any caffeine ∈ your bloodstream—with the negative effects increasing with the dose—makes it harder to fall asleep. When caffeine disrupts your sleep, you wake up the next day with an emotional handicap. You’re naturally going to be inclined to grab a∪ of coffee or an energy drink to try to make yourself feel better.
Withdrawal: Like any stimulant, caffeine is physiologically and psychologically addictive. If you do choose to lower your caffeine intake, you should do so slowly under the guidance of a qualified medical professional. The researchers at Johns Hopkins found that caffeine withdrawal causes headache, fatigue, sleepiness, and difficulty concentrating. Some people report feeling flu-like symptoms, depression, and anxiety after reducing intake by as little as one ∪a day. Slowly tapering your caffeine dosage each day can greatly reduce these withdrawal symptoms.
Disponível em: <https://www.linkedin.com/pulse/article/20140908162020-50578967-caffeine-the-silent-killer-of-success> Acesso em:
10/09/2014, às 14h45min (fins pedagógicos – Adaptado).
“If you do choose to lower your caffeine intake, you should do so slowly under the guidance…”
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