How Long Does Caffeine Last?


How Long Does Caffeine Last

Caffeine is hands down the most popular drug of our time. With the dawning of each day, millions wake up desperate for their fix of this magical compound. Be it through coffee, tea, or energy drinks, most of us consume caffeine daily.

Some folks love it, and they openly (and proudly) talk about their caffeine addiction. Others have mixed feelings about it but usually find it hard to quit. No matter which group you belong to, we’re sure you’re wondering how long does caffeine last in your system? 

As always, the answer is a bit more complicated than you thought, and in today’s article, we’re going to give it to you.

Warning – the following paragraphs may cause a buzz!

See Also: Does Gatorade Expire?

How Does Caffeine Work?

OK, so what’s the fuss about caffeine anyway? Why do people consume so much of it? It wakes us up – duh! But how does it do it? To explain, we’ll have to get a bit scientific and walk you through some basic brain chemistry.

The key player here is a chemical called adenosine. This little guy is secreted by our brain, and as it’s released, it binds to adenosine receptors. The binding makes you feel drowsy as it slows down the (hyper)activity of your nerve cells. 

The process also dilates one’s blood vessels in order to let more oxygen reach the brain while you sleep. Simply, adenosine prepares you for a good night’s slumber.

This may come as a shock, but your nerve cells aren’t very smart, which makes them easy to fool. Caffeine appears just like adenosine to them, and once you consume it, it binds to the adenosine receptors. It quickly takes up all the receptors, and adenosine has no place to bind to anymore—poor adenosine. 

After that, magic happens. Since there’s no adenosine binding, the nerve cells don’t slow down but speed up instead. The neurons start firing at an increased rate, the same as they do in case of an emergency. The signal the pituitary gland to produce adrenaline which has some or all of the following effects:

  • Faster heartbeat
  • Dilated pupils
  • Increase in blood pressure
  • Tightened muscles
  • Open airway

Besides this, the brain’s blood vessels constrict, and this is how medicine with caffeine stops some headaches.

How Long Does It Take For Caffeine To Start Working?

The familiar effect of caffeine (alertness, a.k.a. “the buzz”) kicks in within 15 to 60 minutes of taking it. Other effects may include the need to urinate (or poo), and an increased energy level. All of the above last until the body starts to break down caffeine, after which they slowly go away.

How Long Does Caffeine Last?

The short answer would be 5 hours, but this isn’t entirely true. This time period is its half-life, meaning that if you consume 50 mg of caffeine, 5 hours later, you’ll have 25 mg left in you. In most cases, all the effects will be gone by then, and you’ll just have the leftovers in your bloodstream for a few more hours.

Several factors determine how long the effects of caffeine last in a person’s body, and they include – the dosage, caffeine sensitivity, body weight, and age. 

Sensitivity is perhaps the most significant factor. For folks who are very sensitive to caffeine, the effects can linger for hours, sometimes even days. In some extreme cases, panic attacks or increased anxiety might occur. 

On the other hand, a person with naturally low sensitivity will probably not feel the effects for very long. Also, someone who regularly consumes caffeine may build up a tolerance over time, and eventually barely feel anything after consuming it.

See Also: How Long Does Cold Brew Last?

Which Drinks And Foods Contain Caffeine?

You already know that beverages like coffee, tea, and energy drinks contain caffeine. This is just the tip of the iceberg, and in this section, we’re going to list out all snacks and drinks containing this chemical.

When it comes to drinks, it looks something like this:

  • Coffee – black, latte, cappuccino, even decaf contains a bit of caffeine
  • Tea – green, white, black, yerba mate
  • Soft drinks – almost all major brands
  • Energy drinks – all except when labeled “caffeine-free.”

Foods that contain caffeine include:

  • Chocolate and cocoa 
  • Coffee-flavored ice creams
  • Pre-workout supplements
  • Certain protein bars
  • Some headache medicines

As for the amount of caffeine in some of the products mentioned above, you can check it below:

A shot of espresso (1 oz)50-60 mg
Drip coffee (8 oz)110-170 mg
Instant coffee (8 oz)60-100 mg
Decaf (8 oz)3-5 mg
Tea (8 oz)50 mg
Caffeinated soft drink (12 oz)45-50 mg
Energy drink (16 oz)60-100 mg

What Are The Benefits Of Caffeine?

Caffeine often gets a bad rap, but the fact is that it has many benefits for our health. It’s important to note that not all of the positive effects have been scientifically confirmed, but the evidence is slowly being weighed in.

1. Alertness

A 70 mg dose of caffeine will increase alertness for most people. However, the best way to feel more alert is to get enough sleep, and no amount of caffeine can replace this.

2. Weight Loss

Weight loss is undoubtedly one of the least talked about benefits of caffeine. It can help you shed pounds by suppressing appetite and reducing the desire for food. Also, caffeine stimulates something called thermogenesis, a process in which the body makes more heat (energy) from digesting.

3. Physical Performance

The energy boost that you get from caffeine can improve your physical performance. You will most likely notice an improved endurance capacity and won’t feel as tired after exertion.

4. Reduced Risk From Alzheimer’s And Parkinson’s

According to some research, lifelong coffee drinkers had a lower risk of developing Alzheimer’s disease. On top of this, higher coffee consumption was linked to a reduced risk in Parkinson’s.

What Are The Negative Effects Of Caffeine?

It’s no secret caffeine can disrupt sleep, and this is its most well-known negative effect. The stimulant can make it difficult to fall asleep, and it may even delay your “body clock.” The latter will shorten your sleep time resulting in less rest and rejuvenation. Also, it can inhibit your ability to go into deep sleep.

Even if you take in caffeine in the afternoon or early evening, it can still mess with you when you go to bed. Some medical experts claim that consuming caffeine 5 hours before going to sleep can reduce your sleep time for an hour. 

This effect varies depending on a person’s age, and older folks may feel it more strongly as their bodies don’t process caffeine as fast. Ironically, the elder generations consume the most caffeine in the USA.

Usa Caffeine Consumption Lpc
Source: https://www.caffeineinformer.com/the-most-caffeinated-country

Most adults can consume anywhere between 200 mg and 300 mg a day without feeling any detrimental effects. However, higher doses can lead to sleep issues, increased heart rate, sweating, tremors, and diarrhea.

The adverse effects often occur in folks who consume beverages such as energy drinks or energy “shots,” as they’re packed full of caffeine. 

Another product that may lead to consuming a high-dose is caffeine powder, which is sometimes marketed as a dietary supplement. People take it for an energy boost, performance enhancement, or weight loss.

Many healthcare professionals strongly advise against buying and using caffeine powder. The safe serving size is very small, and it is extremely hard to measure it precisely at home. 

What Are Caffeine Withdrawal Symptoms?

The main reason people have a hard time quitting caffeine is the withdrawal that they have to go through. Common withdrawal symptoms include headaches, low energy, moodiness, and feeling sleepy.

It can be very challenging to push through the day with all these sensations, so it’s no wonder that many folks just go back to consuming caffeine.

How Long Does Caffeine Last – Conclusion

Wow, this sure was a long answer to a seemingly simple question. So, to make sure you remember the main points, we’ll do a quick recap.

The half-life of caffeine in the body is around 5 hours, give or take an hour depending on your metabolism. After this time period has passed, its effects will probably fade away. However, if you’ve extremely sensitive to caffeine, it’ll have a grip on you for much longer.

Caffeine has some good and bad properties. It boosts our energy levels, makes us more alert, and can even reduce the risk of developing neurodegenerative diseases like Alzheimer’s. The downside is that it inhibits sleep, and high doses can cause a lot of issues (increase in heart rate, sweating, tremors, etc.).

It is addictive, and getting off of it might not be so simple. You’ll have to go through withdrawal where you’ll experience symptoms like headaches and sleepiness.

So, what’s our takeaway for today? Caffeine can be fun and very useful unless you overdo it. Consume it responsibly, and you’ll likely be able to enjoy it for years to come.

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