Let's start with the bad news, coffee may not be giving you the benefits you expect, and actually might be making you more tired! I used to think that coffee was a miracle drug that improved everything with no downsides. At one stage I was drinking seven cups a day and spending £75 a week in Starbucks! I didn't feel bad about this as I imagined that the caffeine was giving me energy and making me stronger in the gym. I also love the taste of coffee so l drink it black, meaning all these benefits for just two calories! What could be better?
How caffeine works:
I thought that coffee gave you energy, but actually the mechanism is very different. In his book "Why We Sleep", Mathew Walker talks about sleep pressure. This refers to the build up of a chemical in your brain called adenosine that is strongly implicated in the sleep-wake cycle. The longer you are awake the more it builds up. After 12 - 16 hours its built up enough for us to go to sleep. In the modern world we don't have time for sleep! So we drink caffeine which blocks adenosine from being taken up by its intended receptors. This pauses adenosine's fatiguing effect on the nervous system so we don't feel tired.
Notice that I said 'pauses'. You can think of adenosine like a river and caffeine as a dam. The dam doesn't get rid of water, it simply holds it back. However, the water levels behind the dam continue to increase, so if you remove the dam the water comes flooding through. This is what happens when the caffeine wears off and we crash, feeling more tired than before.
The crash sounds like a chance to drink more coffee!
This is often what happens! The problem is that we quickly build up a tolerance to caffeine and stop feeling its positive affects. As little as 100mg a day is all we need to develop tolerance. That figure might not mean much, so here are some example values:
• A cup of brewed coffee contains about 95 mg on average
• One shot of espresso is around 63 mg
• 250 ml can of Red Bull contains 80 mg
• A tall brewed Starbucks coffee is around 260 mg
I used to drink two grand Starbucks Americanos a day, which is around 660mg! Plus all the brewed coffees I made at home and in the office. My consumption was pretty extreme, but I'd guess that a large percentage of the population are hitting the 100mg a day mark.
Placebo effect
You might be thinking 'I consume more than 100mg a day and still feel the positive effects'. This may actually be the placebo effect. In a recent study, trained men completed one set of bench press to failure having all ingested capsules containing the same inert substance. However, one group was told they had consumed lactic acid, another cellulose (the actual substances all had taken), and the third group was told they had taken caffeine. As you might have guessed, the group that believed they had taken caffeine performed more repetitions and reported lower perceived exertion than the other groups, which had very similar performances.
On the other hand, there have been numerous studies showing no actual benefits on performance for habitual caffeine users in a variety of tests, ranging from playing chess to football. Sticking with lifting weights, a recent study tested resistance trained men habituated to caffeine to see the effects of 3 mg/kg of caffeine on a full-body resistance training workout. To put that number into context, I weigh 77 kg, so for me that would be like consuming three Red Bulls before the workout. The study concluded:
*The oral intake of 3 mg/kg of caffeine by resistance-trained men habituated to caffeine did not enhance the number of repetitions during a medium load full-body resistance training session to failure and had a minimal impact on the prooxidant-antioxidant balance and muscle damage.'
The Vicious Cycle
We now know that caffeine acts as a temporary barrier against fatigue. We can keep rebuilding that barrier, but we've learnt that caffeine habituation reduces the positive affects. Worse still, the more caffeine we have the more we need it due to caffeines detrimental effects on all aspects of our sleep. A meta-analysis of 24 studies on the effect of caffeine on sleep showed that caffeine negatively affected all markers of sleep, including decreasing total sleep and deep sleep time.
The fact that caffeine negatively effects sleep probably does not come as a shock. What does surprise many people is the duration of caffeine's effect. As Mathew Walker explains;
"Caffeine has a half-life of about five to six hours for the average adult. What that means is that about 50% of that caffeine is still circulating in your system five to six hours after you had that cup of coffee. What that also means, however, is that caffeine has a quarter-life of somewhere between 10 to 12 hours.
So in other words, if you have a cup of coffee at let's say 2:00 PM in the afternoon, a quarter of that caffeine can still be circulating in your brain at midnight. So having a cup of coffee in the afternoon may be the equivalent of tucking yourself into bed at midnight, and just before you do, you swig a quarter of a cup of coffee and you hope for a good night of sleep. And that's unlikely to happen for some of us.
" So we wake up feeling tired and immediately turn to coffee as the solution, and the vicious cycle continues. We can get to the point were we need caffeine just to feel normal!
And the good news?!
The good news is we can completely re-sensitise our receptors with just 4-9 days of abstaining from caffeine, depending on how much you used before. Then, if you decide to return to caffeine, you will start to feel the effects and the positive benefits again.
I recently completed a nine day detox and was surprised at how effective it was. My first coffee after the detox gave me a feeling I can't remember having before. It took about 30 minutes to kick in, then I felt much more alert, and strangely my eyes felt like they were more open! Not in a mystical way, I mean physically! I went straight to the gym and, as I record all my lifts, I can see that my numbers were up. However, I always aim to increase my numbers every week, so this might not be entirely due to caffeine. Also, its good to know that if I ever don't have access to caffeine I can still function and am still okay to be around! Well as okay as I usually am at least.
If you feel like you might not be experiencing the benefits of caffeine anymore, you have trouble sleeping, or just don't want your day to have to be based around getting the next hit of caffeine, then you might consider trying a detox.
Some more bad news, sorry!
It is possible that you can suffer withdrawal symptoms when going cold turkey. These can include:
• Headache
• Fatigue
• Anxiety
• Difficulty concentrating
• Depressed mood
• Irritability
• Tremors
Luckily I didn't have any withdrawal symptoms, which surprised me considering my previous high usage. If eliminating caffeine entirely is having too many negative effects, you could instead try tapering down to a low dose.
How I did it
For me drinking coffee was definitely a habit. The very first action take every morning is to boil the kettle ready for my morning Joe. also always had a cup before workouts, which replaced the worse habit of taking pre-workout supplements. One way to break a habit is to replace it. We see this all the time when people are trying to quit smoking they often swap this for an e-cigarette. Legendary former Barcelona manager Johan Cruyff famously swapped cigarettes for lollipops supplied by Chupa Chups! Swapping smoking for sucking was enough for Cruyff, for me it was swapping coffee for mint tea. Decaffeinated tea gave me the warmth, but didn't provide an energy kick, so I also added a fruit smoothie.
I thought I would find the detox very challenging as I am a coffee lover, but it was actually easy. The only time I nearly came unstuck was when I bought some kombucha. Luckily I remembered that this can contain caffeine and checked the label before I'd opened it.
If you want to completely remove caffeine from your diet during the detox you should look out for these products:
• Chocolate
• Decaf Coffee
• Yerba Mate
• Green tea
• Energy drinks
• Some brands of chewing gum
Take away
You now have all the information you need to re-sensitise to caffeine and enjoy the benefits of better sleep and improved performance. You can reintroduce it after nine days if you choose to, though you might find that you're happy to go without it.
If you do decide to get back on the americano's a word of warning; take it slowly! Your first coffee back is going to hit you in way you won't be used to!
If you've taken the trouble to detox then you might consider a new relationship with caffeine for the future. Aiming to stay below 100 mg a day and setting a caffeine curfew a minimum of 8 hours before bedtime would be good first steps. If you want to use caffeine for improved performance then skip the morning coffee and just use it before the activity for best results.
The Starbucks staff might forget your name, but this is a small price to pay to take back control of your life!
References
Placebo bench experiment: https://pubmed.ncbi.nlm.nih.gov/ 37929237/
Habituation study: https://pubmed.ncbi.nlm.nih.gov/37711718/
https://www.masterclass.com/classes/matthew-walker-teaches-the-science-of-better-sleep/chapters/the-buzz-on-alcohol-and- caffeine https://www.healthline.com/nutrition/caffeine-withdrawal- symptoms#headache