THE HEALTH AND FITNESS BLOG
September 14, 2022 – By Dr. Haider Khalid
The Dangers of Caffeine are unaware to many. Caffeine is so far the most commonly used psychoactive substance (1). However, too much caffeine consumption can have adverse effects on your body. Moreover, people who eliminate it from the diet also experience withdrawal symptoms whose severity is pretty challenging to handle.
However, the severity of caffeine’s side effects depends on a person’s genetic makeup (2). Some can consume caffeine without experiencing any symptoms. In contrast, the others can demonstrate serious side effects even after moderate doses.
In this article, you will learn about the negative effects of caffeine on different body organs. Reading this article would help you remove caffeine from your diet.
In addition here on this blog, we have caffeine-free recipes that will be a great alternative to chocolate.
What are the Side Effects of Caffeine on the Brain?
Caffeine is a stimulatory substance that irritates brain cells, creating a sense of fake alertness. The effects of caffeine on the brain only last for a short period, after which a person feels even more tired and lethargic during the rest of the day. Here are some additional effects of caffeine on the human nervous system.
Caffeine is known to cause dependency in its users. According to a clinical study, caffeine alters the chemicals in the brain similarly to the way cocaine does. However, the severity of the effects of caffeine is less compared to cocaine and other habit-forming drugs such as amphetamines (3).
Still, higher doses of caffeine are enough to cause psychological and physical dependency. For example, according to a study, those who consume caffeine excessively do not perform well if they are not given the required daily dose. Most people also exhibit intense caffeine cravings once the caffeine is removed from their diet (4). Moreover, the frequency of intake also influences your dependency on caffeine.
Drug Withdrawal Symptoms
As mentioned previously, caffeine users exhibit withdrawal symptoms once the caffeine is removed from their diet. However, the occurrence of these symptoms varies from person to person. For example, daily caffeine users exhibit more headaches and withdrawal symptoms than occasional caffeine users (5).
Regardless of the dose and frequency of caffeine, users tend to show the following common withdrawal symptoms.
- People with caffeine withdrawal most commonly present with headaches. This is because caffeine constricts the brain’s blood vessels, which is responsible for poor blood supply to the brain, leading to headaches (6).
- Caffeine creates a fake boost in brain activity that keeps you alert for a short period. However, with time you become dependent on caffeine to remain energetic. Once deprived of caffeine, you start feeling drowsiness and fatigue (7).
- Caffeine is known to increase stress hormones in the blood, primarily cortisol. Therefore, sensitive people can start experiencing anxiety about consuming only one cup of coffee (8).
- Other common withdrawal symptoms include difficulty concentrating, depressed mood, increased irritability, and sometimes tremors of the hands.
The brain effects of caffeine are complex and involve changes in the composition of certain chemicals. For example, it reduces adenosine in the brain, which creates a sensation of tiredness. Furthermore, it increases the hormone adrenaline the body produces in stressful situations. These chemical changes are responsible for keeping your brain alert (9).
Adrenaline is a hormone that is also known to cause increased blood pressure. Therefore, high or more frequent caffeine intake can negatively affect the brain, causing anxiety and nervousness. According to American Psychiatric Association, caffeine-induced anxiety is one of the most common caffeine-related syndromes (10).
Therefore, if you are a caffeine user and often feel nervous or jittery, try something better today by eliminating caffeine from your diet.
How Caffeinated Drinks Impair Sleep and Performance?
The adverse effects of caffeine are versatile, affecting almost every aspect of your lifestyle and body functioning. First, discuss how caffeine negatively affects your sleep and daily performance.
People mostly use caffeine to stay awake and counter the feeling of tiredness so that they can perform better during the day. But, they didn’t know that caffeine is evil in disguise. Not only its brain-boosting effects are temporary, but its unique effects on your body also deprive you of sleep.
Simply put, getting enough sleep after caffeine intake isn’t easy. According to a clinical study, most people, especially the elderly, find falling asleep after caffeine intake challenging. Moreover, it also decreases their overall sleeping time (11).
Although the familiar sources of caffeine are tea and coffee, a moderate amount of caffeine can also be present in soda, energy drinks, and several medications. Thus, if you are experiencing insomnia, it’s best to look for possible sources of caffeine in your daily routine.
Impairs Physical and Mental Performance
Initially, caffeine enhances your physical and mental performance. But once the caffeine leaves the body, you start experiencing rebound fatigue and tiredness. According to research, people who consume caffeine in the morning remain sleepy and tired the following day more than non-caffeine users (12).
Most of you start drinking lots of coffee daily to deal with rebound fatigue. But this alters sleep patterns, and you would remain lethargic the next day. Conclusively, the cycle repeats itself the next day. The overall result is that your physical and mental performance is significantly impaired. Thus, if you want to remain physically and spiritually active, remove this artificial stimulant from your diet.
Why Caffeine Causes Weight Gain?
Increased caffeine intake has also been associated with an increase in body weight. However, the direct mechanism of this finding is not adequately understood. Experts primarily relate weight gain due to the effects of caffeine on sleep quality and duration.
As discussed before, caffeine consumption mid-day decreases the quality of sleep. In addition, sleep deprivation is associated with increased appetite and cravings for processed foods. The result is an unnecessary and unhealthy weight gain (13).
Moreover, most people usually don’t drink coffee alone. Instead, they add some pastry to treat them and subside their sugary cravings (14). In other words, just for the sake of some sugary taste on their tongue, people eat more calories while drinking coffee. But, of course, you are probably well aware that extra calories cause your fattening.
The caffeinated drink can itself be the cause of your weight gain. Certain caffeinated drinks, such as soda and cold drinks, contain an excessive amount of sugar in them. Coffee shops and franchises also accept that their coffees have many calories. Thus, these drinks cause weight gain and increase your risk of obesity (15).
Negative Effects of Caffeine on Digestion
A morning cup of coffee can damage your digestive system as well. This is because the caffeine in the coffee causes the release of the gastrin hormone from your stomach. This hormone stimulates the activity and movement of muscles in the colon, a part of the large intestine (16).
Moreover, the laxative effect of caffeine is not limited to the colon only. It also directly affects the receptors in the cells of the whole digestive system (17). Therefore, it increases the overall rate of peristalsis (a wave of contractions and relaxation along the gut wall that keeps the food moving).
Therefore, it is evident from these effects that higher caffeine consumption can lead to more than regular movements in the digestive tract. Conclusively, you would experience loose stools or diarrhea. What’s more? Caffeine also increases the severity of gastroesophageal reflux disease (GERD), leading to stomach ulcers (18).
Side Effects of Caffeine on the Fetus
Caffeine is considered harmful consumed during pregnancy. This is because it affects the development and growth of the fetus inside the mother’s body. Unfortunately, caffeine is metabolized much slower in pregnant women. Therefore, it takes more time to pass the placenta and reach the baby, causing potential adverse effects (19).
Babies born to mothers who consume even a moderate amount of caffeine during the pregnancy tend to have lower than average birth weight. For example, according to a study, even less than 150 mg of caffeine per day increases the risk of low-birth-weight by 13% (19)
Moreover, more than 200mg of daily caffeine consumption significantly increases the risk of miscarriages (20). Increased heart rate, dizziness, diarrhea, and abdominal pain are other mild adverse effects of caffeine on babies born to caffeine-using mothers (21).
Some studies on rats also demonstrate that caffeine consumption during pregnancy can cause bone defects, reduced blood cell formation, and several other physical deformities (22). However, more research is required in this area to develop absolute statements about the human fetus.
Why Women Shouldn’t Drink Coffee?
Although caffeine harms men and women, it drastically affects women’s health, mainly due to its influence on their hormonal systems. For example, according to a study, caffeine consumption is associated with an increased breast cyst formation risk. Cysts are benign growths that can progress to malignancies if they remain untreated for several years (23).
Not only that, but caffeine also increases the risk of cyst formation in ovaries. Women with pre-existing diseases like fibroids and endometriosis are at much greater risk of developing these health-wrecking cysts in breasts and ovaries. Finally, infertility rates are also higher in women who consume caffeinated drinks daily (24).
Is it bad for Your Heart Health?
Caffeine users are reported to have increased blood pressure due to the effects of caffeine on the nervous system. These effects are temporary and much more common in people not used to drinking coffee routinely. However, moderate to high caffeine intake for longer durations can also increase your risk of stroke and heart failure due to the persistent rise in blood pressure (25).
In addition to its effect on blood pressure, caffeine has a direct stimulatory effect on heart muscles. Therefore, the heart rate of caffeine users is usually higher than non-caffeine users. Unfortunately, people with heart disease suffer even more from this effect, leading to a decline in their overall health.
Thus, if you are experiencing rapid heart rate or increased blood pressure, it might be because of an increased caffeine intake. Therefore, look for the amount of caffeine in drinks you consume daily.
How Does Caffeine Affect Your Bladder?
Much like caffeine stimulatory effects on the heart, nervous system, and digestive system, it also has a similar impact on the bladder, leading to increased frequency of urination. So after drinking a cup of tea or coffee, you may urinate more frequently.
According to a study, people who consume only 2 mg of caffeine per pound of body weight can significantly increase urinary frequency and urgency (26). Therefore, reduce your caffeine intake if you are experiencing these two symptoms.
Can You Die from Caffeine Overdose?
People commonly experience headaches, nausea, vomiting, irritability, and jitteriness when consumed in toxic amounts. Death due to caffeine overload is rare. However, caffeine overdose causes seizures, increased blood acid levels, and irregular heart rhythms, which increase your risk of dying (27).
According to a study, about 51 caffeine-related deaths were reported. In another study, 14 out of 26 patients of caffeine overdose are reported to die within the first 24 hours of the caffeine intake (21). But it would be best to keep in mind that moderate to high doses of caffeine are not enough to cause the death of a person. Only those who accidentally consume toxic doses are particularly at risk of death.
The Bottom Line
Up till now, you have read almost everything that science says about caffeine. To conclude, we cannot say that caffeine causes true addiction. But it would be best to avoid it as higher doses or daily caffeine intake is enough to cause physical and psychological dependence, which is undoubtedly harmful. Moreover, the adverse effects of caffeine on the brain, digestive system, bladder, hormonal levels, and heart are more than enough reasons to remove it from your diet.
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