The way we observe and interact with our world happens through our nervous systems. It is how we learn about our surroundings and how we function within those surroundings. But what would happen if something was affecting our nervous systems in ways that could both help us and harm us? Truth be told, there is. Caffeine is renowned for being the world’s most widely consumed psychoactive drug, but it is also known for literally shaking up our bodies by affecting our nervous systems. The drug can be good for us in some ways, but also bad in other ways.
This makes it tricky and debatable whether caffeine is more helpful or more harmful. Inside the neurotransmitter, caffeine causes receptors to receive more dopamine chemicals by blocking off adenosine chemicals from getting through. Adenosine is known for preparing the body for rest, whereas dopamine is known for muscle control, pain, pleasure, and emotions. The more caffeine a person consumes, the more hyper aware your body becomes in dopamine’s aspects.
And because the neurons are receiving little to no adenosine chemicals, the same person will have trouble falling asleep or resting for the next few hours. Note that caffeine is able to significantly block adenosine effects on A2A (most potent) and A1 receptors already at the low concentrations achieved after a single cup of coffee. ” (Fredholm, Battig, Holmen, Nehlig, and Zvartau, 1999). Caffeine affects the Central Nervous System most severely by imbalancing the reception between dopamine and adenosine chemicals. Due to the lack of adenosine, there is an increase in the brain’s neural activity, a reduction of blood flow to the brain, and a decrease of the body’s energy metabolism.
Because neural activity is increased, this leads to a decrease in drowsiness. There are also increases in thought processing and temporary mental awareness. The reduction of blood flow to the brain cause headaches, dizziness, and the lose of fine motor coordination. And lastly, after long-term consumption of caffeine, energy metabolism decreases and leads to adrenal fatigue. Adrenal fatigue has the following common symptoms: fatigue and lack of energy, trouble sleeping, difficulty concentrating, consistently feeling sick, weight gain, and mild depression. Caffeine doesn’t stop there though.
In addition, caffeine affects involuntary responses in the body by raising the person’s heartbeat, worsening essential tremors, exciting the small intestine, promoting bowel movements, increase in blood pressure, and causes the person to take short, rapid breaths of air. The Autonomic Nervous System goes berserk when a person’s body is on caffeine. Even just a little caffeine makes the heart begin to beat faster than normally. An experiment performed by Kenny Howell, Samuel Lopez, Tiffany Marshall, and Maggie Peters, which was titled Caffeine’s Effects on Heart Rate, proves that the heart rate can be affected by caffeine.
In their experiment they gave their subjects 300 milligrams of caffeine. “Our results indicated that caffeine consumption does have a significant effect on heart rate. ” As stated by Howell, Lopez, Marshall, and Peters (2003). Their results were significant enough to the point where the subjects’ heartbeat rates added ten extra beats per minute, as compared to the control group (who was given no caffeine at all). Interestingly, adrenaline is the driving force of the “fight or flight” response.
The term “fight or flight” describes a mechanism in the body that enables humans and animals to mobilize a lot of energy rapidly in order to cope with threats to survival. ” (The Counseling and Mental Health Center, 2015) Caffeine has a hand in this response as well though. Caffeine triggers the release of adrenaline hormones. This is why someone feels “on-edge” after drinking a lot of coffee. Consumption of caffeine induces feelings of anxiety and stress. In other words, the “fight or flight” response is taking control of the mind, even if there is no major problem occurring.
In turn, when the effects of caffeine wear off, the parasympathetic system kicks in and the person essentially “rests and digests” what had happened. Because caffeine improves cognitive tasks, such as attention and memory, it is easy to recall what happened while the person was being affected. With this information, let’s hop back to the Central Nervous System again. The frontal lobe is responsible for short-term memory and attention, which are the cognitive actions that caffeine makes more aware.
This part of the brain controls many other cognitive features, which could also be controlled by the substance. The frontal lobe isn’t the only place being changed up by the caffeine though. The hippocampus, which is strictly in charge of short term memory and learning, takes a hard hit from prolonged, low doses of caffeine. The function of the hippocampus is greatly slowed down, making it hard to recall things that are recent. Furthermore into the brain, when a person consumes too much caffeine, the chemicals in the cerebellum become unbalanced, which in return makes you just as unbalanced.
Experiments with caffeine and the thalamus have shown that caffeine is able to suppress chemical balances which allow the mind and body to sleep. “It was found that caffeine, 0. 1 to 0. 5 mg/kg i. v. , markedly suppressed and that amphetamine, 0. 1 to 1 mg/kg i. v. , markedly augmented the spontaneous firing rates of medial thalamic neurons. It was also demonstrated that amphetamine was capable of activating the medial thalamic neuronal activity while it was suppressed by caffeine. ” (Chou, Forde, and Hirsh, 1980).
The suppression of the thalamus also results in restlessness and awareness, which goes hand-in-hand with the cognitive actions of the frontal lobe. And, lastly, caffeine affects your emotions and how you feel. This can be found in the part of the brain called the amygdala. The amygdala control strong emotions, like fear and anger. Caffeine creates anxiety and stress, which can boost both fear and anger levels. Anxiety will mainly affect the fear, whereas the stress will mainly affect the anger. It doesn’t take a lot of caffeine to do all these things to the brain is the most fearful part though.
Two to three cups of coffee, one right after the other, is enough to wreck havoc on the poor brain. And likewise, the Endocrine System has many parts to it which are mostly influenced by caffeine. Because neurotransmitters are blocked off from receiving adenosine, the body is unable to rest. This affects the Pineal Gland, the sleep capital of your mind, because no rest means no sleep. In the thyroid, metabolic rates are increased throughout the body. Some people lose weight because of this, but no more than a pound or two (which becomes easily regained).
And even though it doesn’t make you grow a few inches taller, caffeine makes the hypothalamus and the pituitary gland hyperactive. The signals inside these parts of the brain multiply slightly and race off in incredible rates. The pituitary gland also releases a hormone called ACTH, which gets sent to the adrenal glands. These glands are known for producing epinephrine and inducing stress. The epinephrine produced is better known as the before mentioned hormone: Adrenaline. Inside the parathyroid though, calcium becomes produced at stunningly low rates, which causes a calcium deficiency within the bones.
As stated by Lu, Farnebo, Branstrom, and Larsson (2013), “A physiological high dose of caffeine inhibits PTH secretion in human parathyroid cells, possibly due to a decrease of the intracellular level of cAMP. The observation demonstrates a functional link between caffeine and parathyroid cell function. ” The research team also made observations such as, “Caffeine is a highly consumed psychoactive substance present in our daily drinks,” and “Independent studies have reported associations between caffeine consumption, low bone mineral density, and urinary calcium loss, as well as impaired bone development in vitro and in vivo.
Putting the parathyroid aside and moving onto the pancreas, caffeine affects the sensitivity of insulin. Too much caffeine can be linked to causing Type 2 diabetes. Also, a person who already has diabetes needs to regulate their caffeine intake, because caffeine can cause a rise in blood glucose. So far, caffeine has had strong effects in all the major glands in the endocrine system. The case for the gonads is different, however. Caffeine does not have an affect on sex hormones at all. However, caffeine does pose a problem to people who are pregnant.
So despite caffeine not having an effect on sex hormones, caffeine still has other major impacts on the body that can disrupt development of a fetus. Therefore, pregnant persons should take caffeine in moderation. Pregnant people aren’t the only people who need to take caffeine in moderation though. Most people are used to consuming large amounts of caffeine during 24-hour periods. Because of this, the body can bring to rely on the drug, causing addiction. According to Stoppler (2014), an accredited medical author, “Up to 90% of adult Americans consume caffeine every day.
Most commonly, the caffeine is in coffee, tea, soft drinks, and chocolate. This adds up to an average of about 280 mg of caffeine per day, or the equivalent of about two cups of coffee. ” Even though the intake of caffeine is common, it still poses the problem of addiction. People who are heavy consumers of caffeine find that they have a psychological dependence on it. The same consumers also experience withdrawal symptoms when they do not get caffeine in their system within 12-24 hours from the last time they had caffeine.
These withdrawal symptoms include, “headache, fatigue, or drowsiness; depressed, irritable mood; difficulty concentrating; flu-like symptoms of nausea and/or vomiting; and muscle pain or stiffness. ” (Stoppler, 2014). The best recommendation for people who rely on caffeine but are trying to reduce caffeine levels are to simply cut back on the caffeine little by little each day until satisfaction is reached. By doing this, withdrawal symptoms are skipped over and the desired conclusion is met. Overall, caffeine has obvious positives and negative to it.
Positives being increased attention and alertness, decreased fatigue, improved cognitive skills, and increased metabolic rate. The negatives, on the other hand, including anxiety and stress, increased blood pressure, increased stimulation of urination, and reduced fine motor movements. Each person is affected slightly differently by caffeine, however, because everyone intakes different levels of the substance. Those who take too much caffeine though suffer more included negatives, such as insomnia, reflux, muscle spasms, heart palpitations, stomach ulcers, and more.
The importance of moderating personal intake of caffeine should be stressed more than it is in society. Even though there are ups and downs to caffeine, there always seems to be more downs. Caffeine is near impossible to completely avoid though. It’s in our drinks, it’s in our food, it’s in our medicine. There is no escape to this drug, but that’s okay. Low levels of caffeine are healthy for the body, however, so don’t let all the negatives seem too discouraging. Enjoy the taste of coffee and tea (in moderation though).
