What is it?
Caffeine is a natural stimulant that is found in the seeds, leaves, and fruits of some plants. It belongs to a class of compounds called xanthines, which are known for their stimulant properties.
The origins of caffeine are not entirely clear, but it is believed to have originated in the ancient civilisations of Ethiopia or Yemen. According to legend, a shepherd in Ethiopia noticed that his goats became more energetic after eating the berries of a certain plant. He tried the berries himself and found that they had a stimulating effect, leading to the discovery of coffee.
Coffee was first cultivated and consumed in Ethiopia, and then spread to the Arabian Peninsula, where it became a popular beverage. From there, it spread to Europe and the rest of the world, becoming one of the most widely consumed beverages in the world.
How does it work?
Caffeine is a stimulant that affects several chemicals in our brain, including adenosine, cortisol, dopamine, adrenaline, and norepinephrine.
Adenosine is a naturally occurring substance that accumulates in the brain throughout the day, as this chemical builds up in our brain throughout the day, we start to feel more tired, leading to drowsiness and a desire to sleep at night.
When we sleep, our brain breaks down this chemical, which helps us feel more awake and alert when we wake up.
So essentially, adenosine helps to control our sleep and wakefulness by making us tired when it builds up and making us feel more awake when it goes away during sleep.
Caffeine does not increase energy – it is borrowing energy, altering the time at which adenosine is released.
Cortisol is a stress hormone that is naturally released by the adrenal glands in response to stress or low blood sugar levels. Cortisol levels are naturally high in the morning (they normally peak – around 8:30 a.m.), which helps to promote wakefulness and alertness.
Dopamine is a neurotransmitter that is associated with pleasure and reward. Caffeine can increase dopamine levels in our brain, which can make us feel more motivated and focused.
Adrenaline and norepinephrine are hormones that are involved in our body's fight or flight response. Caffeine can increase the release of these hormones, which can make us feel more alert and ready for action.
Overall, caffeine works by blocking adenosine receptors in the brain, which helps us feel less tired and more alert. At the same time, caffeine can increase cortisol, dopamine, adrenaline, and norepinephrine levels in our body, which can affect our mood and energy levels in different ways.
What are the benefits?
Increased alertness and focus: Caffeine can improve cognitive function, including alertness and focus, which can help athletes better concentrate on their sport and make quicker and more accurate decisions.
Increased endurance: Caffeine has been shown to increase endurance performance by reducing the perception of effort and delaying the onset of fatigue. This can allow athletes to exercise for longer periods of time or at a higher intensity.
Increased power and strength: Caffeine can also improve power and strength performance by stimulating the central nervous system and increasing muscle activation. This can be especially beneficial for activities that require short bursts of high-intensity effort, such as sprinting or weightlifting.
Increased fat metabolism: Caffeine has been shown to increase the use of fat as a fuel source during exercise, which can help spare glycogen stores and delay the onset of fatigue.
Reduced perception of pain: Caffeine can reduce the perception of pain during exercise, which can allow athletes to push themselves harder and perform at a higher level.
When?
It is important not to have caffeine immediately upon waking with regards to both cortisol and adenosine, two important biological factors that play a role in regulating wakefulness and alertness.
Cortisol levels are naturally high in the morning and adenosine levels are naturally low, by consuming caffeine immediately upon waking you can interfere with your natural cortisol and adenosine rhythm.
In addition to interfering with your body's natural rhythm, by consuming a cup of coffee within the first hour or two of waking, you are likely not getting caffeine’s full benefits, because your body is already at its peak cortisol level and it's lowest level of adenosine – naturally trying to get you going for the day ahed.
This is why caffeine consumption is more effective when consumed later in the morning as opposed to first thing.
After cortisol peaks at around 8:30 a.m, it begins to decline, but then it spikes again around noon.
So, 9:30 a.m. to 11:00 a.m. might be the most advantageous window for getting the most benefit from your caffeine/coffee consumption, without interfering with the body's natural rhythm.
Although cortisol levels do drop off again in the afternoon, that’s probably not the best time for another coffee pick-me-up because it could interfere with your sleep due to the half life of caffeine.
Half Life
Caffeine has a half-life of about 5-6 hours in most people. This means that after consuming caffeine, half of the caffeine will be metabolised and eliminated from the body within 5-6 hours. However, the remaining caffeine can stay in the body for longer, depending on individual factors such as age, metabolism, and liver function.
The half-life of caffeine means that it takes several hours for the effects of caffeine to wear off. For example, if someone drinks a cup of coffee containing 100mg of caffeine at 3 pm, by 9 pm, there will still be about 50mg of caffeine in their system. This remaining caffeine can affect the quality of sleep, especially if someone is sensitive to caffeine or has consumed caffeine later in the day.
Therefore, it is generally recommended to avoid consuming caffeine several hours before bedtime to minimise its detrimental effects on sleep. Some experts recommend as long as 12 hours between caffeine consumption and bed time.
How much?
Bodyweight is a good measure of proper caffeine dosage for your body: 1-3mg/kg body weight per sitting will likely provide you with all the benefits without the jitters.
If you consume caffeine regularly, your body can become accustomed to the effects of caffeine, and you may need to consume more caffeine to achieve the same level of alertness or performance enhancement as before. This can lead to a cycle of increased caffeine consumption, which can lead to negative side effects such as jitteriness, anxiety, and sleep disturbances.
To avoid developing a tolerance to caffeine, it is recommended to limit daily caffeine intake to moderate levels, typically less than 400 mg per day. Additionally, cycling caffeine use by taking breaks from caffeine consumption or reducing intake for a period of time can help prevent a tolerance from developing.
Wrapping Up
Caffeine is a widely used and well-known stimulant that can provide several benefits when consumed in moderation. It can enhance cognitive function, physical performance, and mood, and it is found in many common foods and beverages. However, excessive caffeine consumption can lead to negative side effects, including anxiety, sleep disturbances, and caffeine tolerance.
Therefore, it is important to consume caffeine in moderation, be mindful of personal tolerance levels, and avoid consuming caffeine too close to bedtime to optimise its benefits and minimize any negative effects.
Comments