By Otis T.K.
Academics often quip, “It’s not research, it’s me-search.” So perhaps the most telling sign that someone is consuming too much caffeine is when they've taken the initiative to open their laptop and search for it.
This isn’t you, obviously. You’re just browsing the internet exploring an article like this because you're curious. But for those poor, jittery souls who do have a problem with caffeine, here are some unmistakable signs.
Sleep Suffers
Coffee can have a quarter-life of 12 hours. That means if you drink a cup at noon, a quarter of that caffeine could still be circulating in your system at midnight. That’s akin to placing a cup of coffee on your bedside table and having a few sips just before you try to sleep.
While you might still manage a restless few hours of something resembling sleep, caffeine particularly disrupts deep sleep. Often confused with REM sleep, deep sleep is its own distinct stage. During this phase, your core body temperature drops, eye movement ceases, and brain waves slow down. This allows for:
- The pituitary gland to release human growth hormone, promoting muscle growth and recovery.
- Low-frequency brain waves to synchronise many neurons, allowing your brain to consolidate memories. The mental clutter is cleared.
- A boost to the immune system, especially in natural killer cells responsible for combating dangerous cancers.
Your liver's speed in metabolising caffeine, and thus your ability to achieve deep sleep after drinking coffee, largely depends on an enzyme called CYP1A2. Some people may be able to consume large amounts of caffeine and still achieve deep sleep. But for most of us, coffee late in the day is like that mate who said they'd pop by for a quick visit but is still lounging on the sofa hours later.
In Michael Pollan’s recent book, This is Your Mind on Plants, he notes, “Here’s what’s uniquely insidious about caffeine: The drug is not only a leading cause of our sleep deprivation; it is also the main remedy we rely on to address the problem.”
Increased Anxiety
While a small amount of caffeine can offer various health benefits, including improved digestion and cognitive function, excessive consumption can elevate blood pressure and stress. Caffeine is a stimulant, and stimulants can exacerbate underlying anxieties through a surge in cortisol. If you're predisposed to anxiety, caffeine might just fan the flames.
Caffeine is the only psychoactive drug that we routinely give to children. Since 1977, there has been a 70% increase in caffeine consumption among children. Coupled with stressors like social media, many young people are facing higher rates of anxiety than ever. A recent study suggested that approximately 4.4 million children in the US have diagnosed anxiety. And caffeine can accumulate quickly. A standard cup of coffee contains anywhere from 50-400 mg. Add an energy drink, black tea, and chocolate bars, and one can quickly reach excessive levels.
Caffeine Use Disorder (Yes, It’s Real)
Thanks to Roland Griffiths, a leading researcher in psychoactive substances, the diagnosis of caffeine use disorder is now included in the DSM-5, the definitive resource for psychiatric diagnosis. Griffiths highlighted the following symptoms:
- Withdrawal symptoms: If you miss your morning cup and quickly develop a pounding headache, you might want to heed the warning your body is giving. Those with caffeine use disorder will experience withdrawal symptoms such as irritability and fatigue when reducing or quitting coffee.
- Tolerance: 90% of people globally consume caffeine daily, making it the world’s most-used psychoactive drug. As tolerance to caffeine builds, many of its users are compelled to increase their dose, thus blurring the line between benefit and detriment.
- Continued use despite problems: As Griffiths mentioned in an interview with Michael Pollan, “There’s nothing inherently wrong with an addiction if you have a secure supply, no known health risks and you’re not offended by the idea.” But if you find yourself becoming anxious, irritable, or sleeping poorly, yet still continue to consume large amounts of caffeine just to get through the day, it might be time to reconsider your relationship with caffeine.
MUD RECOMMENDS: To learn more about caffeine overconsumption and its impact on sleep, we recommend checking out Why We Sleep by Matthew Walker. The Caffeine section of Michael Pollan’s This is Your Mind on Plants (also available as a stand-alone audiobook) is also insightful.
