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Unlocking Morning Vitality: My Journey with the 90-Minute Coffee Rule

Written by Dr. Daniela Steyn

Do you ever struggle with afternoon fatigue? I've got a solution for you!

I have been struggling with an afternoon slump for as long as I can remember. I vividly remember during Medical School how I noticed that the lectures between 2- 6 pm felt unbearably long. When I started working it got even worse, working through many nights as a doctor delivering babies and being up with my own babies. I have tried many different strategies to prevent afternoon fatigue.

Until a couple of years ago, I would typically start my morning with a 5am coffee before my early morning run or swim. And then, another cup during breakfast with my family. At lunch I would always drink a coffee to ensure I have energy for the after school pickup, activities & dinner prep.

Today, I'd like to share a journey that has profoundly impacted my approach to mornings—a practice that has been a game changer for me. I have been recommending it to my patients and it has significantly improved energy and increased overall well-being for many of them. I know it will make a significant difference in your life too.

The Relationship Between Cortisol, Adenosine and Caffeine

What led to me changing my morning routine was a podcast that I stumbled upon by Dr. Mark Huberman. He explained that caffeine within 90 minutes of waking up, displaces all the adenosine in your body, leading to an afternoon slump. I researched it further. Let's look at how it works:

Cortisol: The Morning Booster

As we awaken, our body naturally experiences an increase in cortisol levels—a stress hormone that plays a pivotal role in making us feel alert and awake. Cortisol is like your body's natural alarm clock. It gets released when you wake up, giving you that boost of energy to start the day. Think of it as your body's way of saying, "Time to get up and be active!" It helps you feel alert and ready to tackle the day's tasks. But, here's the catch—consuming caffeine during this cortisol surge can, surprisingly, dampen the effects of both cortisol and caffeine. This could mean that that morning cup of coffee might be less effective in boosting energy levels than we thought.

Adenosine: The Sleepiness Messenger

In the morning, our bodies naturally release a neurotransmitter called adenosine, which accumulates in the brain as a result of daily activities. Adenosine plays a significant role in regulating sleep and wakefulness. It's a messenger in your brain that lets you know when it's time to wind down. As you go through your day, adenosine builds up and binds to specific receptors known as adenosine receptors, making you feel a bit tired. This buildup is your body's way of saying, "Hey, we need some rest soon."

Caffeine: The Temporary Alertness Booster

When we consume coffee or other caffeinated beverages, one of the primary effects of caffeine is its ability to block adenosine receptors. Caffeine structurally resembles adenosine and can therefore bind to the same receptors without activating them in the same way adenosine does. This binding action effectively prevents adenosine from attaching to its receptors, leading to temporarily reduced feelings of drowsiness and increased wakefulness.

Here's the twist: when caffeine wears off, the real adenosine is still hanging around. It didn't go away, it was just waiting in the background. So, when caffeine's effects fade, adenosine steps in and says, "Time for a snooze!" This can lead to that familiar afternoon slump. What's really interesting to me is that waiting 90 minutes post-awakening to indulge in my caffeine fix could allow adenosine levels to slightly rise and be metabolized naturally. This subtle adjustment might just amplify caffeine's receptor-blocking powers, causing me to be more alert and focused.

Circadian Rhythm

Additionally, at the core of our bodily functions lies a fascinating timekeeping system known as the circadian rhythm. This internal clock guides various physiological processes, such as sleep-wake cycles, hormone production, body temperature regulation, and more. It's like a finely tuned orchestra, ensuring that our body's functions work together with the natural rhythms of day and night.

Our circadian rhythm is mostly influenced by external cues, with sunlight being a dominant factor. When sunlight enters our eyes, it triggers numerous biological responses that help regulate our internal clock. As the sun rises, our body receives signals to be alert and active, while as it sets, it prepares for rest and rejuvenation.

As such, there are numerous studies that shows that taking a walk outdoors, before your morning coffee, can be beneficial for several reasons:

  • Sunlight Exposure: As mentioned earlier, sunlight is a potent regulator of our circadian rhythm. By going for a walk in the morning, you're allowing your body to receive a healthy dose of natural light. This exposure can help set your internal clock, making it easier to wake up feeling refreshed and fall asleep more easily at night.

  • Boosting Mood: Sunlight triggers the release of serotonin, often referred to as the "happy hormone." This can lift your mood and enhance your overall sense of well-being, providing a positive start to your day.

  • Enhancing Alertness: Exposure to natural light suppresses the production of melatonin—the hormone that induces sleepiness. This, in turn, increases your alertness and cognitive function, making you more focused and ready to tackle the tasks of the day.

  • Regulating Sleep Patterns: A morning walk can help in resetting your internal clock, particularly if you've been experiencing disruptions due to night shifts or irregular sleep patterns. By aligning your circadian rhythm with external cues, you're enhancing the quality of your sleep.

  • Connecting with Nature: Being in nature has a calming effect on our nervous system. The tranquility and beauty of outdoor surroundings can reduce stress and promote relaxation, setting a positive tone for the day ahead.

  • Physical Activity: Walking is a gentle form of exercise that gets your blood flowing and muscles working. Even a short walk can contribute to improved cardiovascular health, muscle tone, and overall fitness.

Tying this back to the 90-minute coffee rule, I encourage you to combine the two practices. Delaying your cup of coffee in the morning by 90 minutes and using that time to take a walk outside could create a synergy between your body's circadian rhythm and your caffeine consumption. This approach can lead to improved energy, enhanced mood, and a deeper connection to your body's innate wisdom. By delaying my coffee intake by 90 minutes, I'm not only aiming for better energy levels and improved sleep quality but also striving to reduce my caffeine dependency. Introducing caffeine too early in the day can prompt your body to rely more on the caffeine than its natural cortisol release. Remember, it's these small, intentional shifts that lead to remarkable changes. Needing that first-morning coffee is entirely okay, especially considering the unique demands of our lives. But making slight changes, even if we don't get them perfect every time, can ripple into positive impacts on our well-being. I invite you to embrace the "90-Minute Rule" with me and witness the transformation it brings to your daily vitality and focus. Let's journey together towards an energized, mindful start to each day.

To learn how we can help you optimize your energy, visit us at our flagship clinic in Oakville, Canada. Email for more information.


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