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This article continues our discussion on methods to enhance the quality of sleep, a crucial measure of overall mental and physical health. Stimulants like coffee, when not consumed mindfully, can impact the quality of our sleep, particularly the deep sleep essential for the restoration and rejuvenation of brain, heart and gut. As an avid coffee lover myself, I'm not suggesting giving it up! However, this article delves into the scientific basis of how coffee works its magic in our bodies and brains. Understanding this can foster a healthier relationship with your cup of Joe without losing on the wonders of sleep. Let's explore this together.
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cof·fee /ˈkôfē,ˈkäfē/ noun The berries harvested from species of Coffea plants.
Coffee is made by brewing roasted coffee beans, either arabica or robusta (these two beans comprises 99% of all the coffee consumed in the world). Some prefer the boldness of espresso, or the smoothness of americano or black coffee (which is my preferred choice). Then there are many milk-based coffee options available.
How do you like your coffee?
It's caffeine that gives coffee its appeal and energy-boosting properties. Interestingly, due to these appealing psychoactive properties, coffee has faced five historical attempts at being banned. With the help of scientific studies, we now have a clear understanding of how coffee works.
What is Caffeine ?
Caffeine is a naturally occurring substance found in the seeds, fruits, nuts, or leaves of various plants, including coffee beans, tea leaves, cacao pods, and kola nuts. It is a bitter, white crystalline compound. It is a central nervous system stimulant which means it can cross the blood brain barrier and affect the biochemistry of the brain. It can increase alertness, mood and cognitive performance.
Caffeine is the most widely used psychoactive substance globally.
Caffeine is naturally present in coffee, tea, dark and milk chocolates, some energy drinks which may come from plant ingredients such as yerba mate and guarana. It is important to note that synthetic caffeine in large amounts is also added in cola soft drinks, energy monster drinks, red bulls, hot chocolates and a variety of over-the-counter medications, including cough, cold and pain remedies.
The caffeine content of your coffee can vary based on several factors: the brewing method, water temperature, coffee volume, grind size of the beans, and the bean variety. The visual illustration below provides a clear overview of caffeine content.
Important Note: In Canada, manufacturers of products that contain naturally occurring caffeine are not required by law to list caffeine as an ingredient on the label. Only added caffeine must be listed.
Life cycle of Caffeine in body
After consumption, caffeine is rapidly absorbed through the gastrointestinal tract, typically within 15 to 45 minutes, reaching peak levels in the bloodstream. The peak concentration of caffeine in the bloodstream occurs somewhere between 15 minutes and 2 hours after ingestion, depending on various factors such as the form of caffeine consumed, the rate of absorption, and individual differences in metabolism. This peak concentration represents the moment when caffeine levels reach their highest point in the body, resulting in the most pronounced effects.
Caffeine is distributed throughout the body via the bloodstream. It can also cross the blood-brain barrier, allowing it to affect the brain, leading to its psychoactive effects (detailed in next section).
In the liver, caffeine undergo metabolism, where it breaks down into three primary metabolites which are excreted from the body through urine.
The half-life of caffeine varies from person to person but is typically between 3 to 7 hours. This means that it takes this amount of time for the concentration of caffeine in the bloodstream to decrease by half. Factors such as individual metabolism, age, liver function, and whether a person is a regular caffeine consumer or not can influence caffeine metabolism and half-life.
What Caffeine does to your Brain?
Caffeine acts as a stimulant or psychoactive by blocking the binding of adenosine to its receptors in the brain. Adenosine is a neurotransmitter (messenger) that promotes relaxation and sleepiness by binding to its receptors in the brain. This indirectly affects the release of neurotransmitters like norepinephrine, dopamine, acetylcholine, and others, altering mood, memory, alertness, and cognitive function. To put it simply, Adenosine signals sleepiness and caffeine blocks that sleepy message and in turn boosts the happy signals, making you feel alert and energized.
Caffeine is a vasodilator, meaning it opens up blood vessels in the brain, allowing for increased blood flow and oxygen delivery. This can help alleviate headaches caused by constricted blood vessels.
Caffeine signals the brain to produce adrenaline and dopamine, the body's "fight-or-flight" and "feel-good" hormones, respectively. This can lead to feelings of increased energy, alertness, and even anxiety in some individuals.
These are the reasons why we crave coffee when we feel sleepy, need to concentrate on tasks, feel anxious before deadlines or meetings, face public speaking, or encounter gloomy weather. Coffee seems to offer a solution for every challenge!
However, it's crucial to recognize that excessive caffeine intake, especially at inappropriate times, can pose serious health risks. Let's delve into that further.
How much is too much?
Determining how much coffee is too much can vary from person to person, as individual tolerance levels can differ. However, health experts generally advise limiting caffeine intake to around 400 milligrams per day for most adults, which is roughly equivalent to 4 cups of brewed coffee.
Consuming more than this amount can lead to negative side effects such as insomnia, nervousness, restlessness, increased heart rate, upset stomach, muscle tremors, and even more severe issues like heart palpitations or anxiety disorders in sensitive individuals. It's essential to listen to your body's signals and adjust your coffee consumption accordingly to avoid these adverse effects.
Cut off time for drinking coffee?
Avoid caffeine consumption in the late afternoon or evening to prevent interference with sleep quality. Generally, it's suggested to refrain from drinking coffee or other caffeinated beverages at least 6 hours before bedtime. This allows sufficient time for the effects of caffeine to wear off, reducing the risk of sleep disturbances and ensuring a restful night's sleep. Adjustments may be necessary based on individual tolerance levels and sensitivity to caffeine.
The ideal cut-off time for drinking coffee varies from person to person due to differences in caffeine sensitivity and metabolism. However, to avoid disturbances in sleep quality, it's generally recommended to stop consuming caffeinated drinks after 3 pm. If adjusting to this change proves challenging, consider opting for decaffeinated options to support better sleep habits.
Are you dependent on Coffee?
Coffee is perfect for combating that midday slump, but it's more than just a pick-me-up. It's about the experience—the ritual, the camaraderie, the joy. However, it's essential to be in control of when we choose to indulge in coffee, rather than letting it dictate our habits.
Coffee can be addictive due to its caffeine content. Caffeine is a brain stimulant that can lead to physical dependence when consumed regularly.
Recognizing coffee addiction involves being aware of both physical and psychological signs. Here are some indicators:
Feeling the need for caffeine to function normally or to avoid withdrawal symptoms like headaches or fatigue.
Needing more coffee over time to achieve the same effects.
Experiencing headaches, irritability, fatigue, or difficulty concentrating when attempting to cut back or stop coffee consumption.
Trying and failing to reduce coffee intake despite wanting to do so.
Thinking about or planning coffee consumption frequently throughout the day.
Feeling that coffee consumption interferes with work, relationships, or other activities.
Pay attention to when you reach for your coffee
Is it immediately after waking up?
Is it during the midday slump?
Is it before, during, or after meetings or deadlines?
These habits offer insights into your coffee consumption patterns and potential dependence. They can also shed light on underlying health conditions.
For instance, relying on coffee upon waking suggests poor sleep quality; ideally, after a restful night, you should feel naturally refreshed and motivated.
If you find yourself turning to coffee during stressful situations like meetings or demanding tasks, it may indicate elevated cortisol levels due to anxiety or stress. While coffee initially boosts motivation, it can lead to a subsequent energy crash, perpetuating a vicious cycle. Recognizing this pattern is the first step toward breaking it and exploring more effective ways to manage stress and anxiety.
Midday presents a natural dip in our energy levels, a part of our body's circadian rhythm. It's during this time that many of us reach for a cup of coffee to combat the sluggishness. However, it's important to understand that while coffee can provide a temporary boost, it's just that—temporary.
Strategies for maintaining a non-addicted relationship with coffee
After acknowledging any dependence on coffee, taking charge of your health is crucial.
Follow these strategies carefully to regain control:
Enjoy coffee in moderation, keeping daily intake within recommended limits (about 400 mg of caffeine per day for most adults).
Balance coffee consumption with adequate hydration by drinking water throughout the day to prevent dehydration and maintain energy levels.
Opt for high-quality coffee and savor it rather than drinking multiple cups throughout the day.
Pay attention to how your body responds to caffeine and adjust consumption accordingly. If you're feeling jittery or anxious, consider cutting back.
Prioritize healthy habits such as regular exercise, balanced nutrition, and adequate sleep to support overall well-being and reduce reliance on caffeine for energy.
Explore caffeine-free alternatives like herbal tea or decaffeinated coffee to reduce overall caffeine intake without sacrificing enjoyment.
Conclusion
The caffeine in coffee works by blocking adenosine receptors in the brain, which temporarily prevents us from feeling tired. But as the caffeine wears off, adenosine floods back in, often leaving us feeling even more fatigued than before. So while coffee can offer a quick pick-me-up, it's essential to remember that the energy boost it provides is short-lived, and relying on it too heavily can disrupt our natural energy rhythms in the long run.
Enjoy your coffee but to keep the good vibes going, consider these tips:
Have your first cup of coffee at least an hour after waking up, and spend 20 minutes soaking in some sunshine to kickstart your day on a positive note.
Avoid coffee and other caffeinated drinks after 3 pm to promote better sleep quality.
If black coffee feels too intense, try adding milk to mellow out the flavor.
Remember to drink water after your coffee, as caffeine can have a diuretic effect.