Caffeine: What Is It? What Are Its Benefits?

What Is Caffeine?

Caffeine is a natural chemical with stimulant effects^[1]. Every day, millions of people rely on caffeine to wake up or recover from afternoon fatigue. Therefore, this stimulant is one of the most widely used substances in the world^[2]. It is rapidly absorbed by the body after consumption. It then works by blocking neurotransmitters that relax the brain and cause you to feel tired^[3]. The name of these neurotransmitters is adenosine. Adenosines accumulate in the body during the day and cause you to get tired and want to sleep. Thus, caffeine helps you stay awake by binding to adenosine receptors in the brain without activating them. This is how caffeine helps you spend the day more energetically by reducing fatigue^[3]. In addition, one of the most important features of this natural chemical is that it shows its effects quickly. For example, it takes only 20 minutes for the amount found in a cup of coffee to reach the bloodstream, and at most 60 minutes for it to reach its full effectiveness^[2].

What Contains Caffeine?

Caffeine is a substance contains naturally in more than 60 plants, including the following. The caffeine content of these substances varies. The most well-known caffeinated foods are as follows:

• Coffee beans
• Tea leaves
• Cola
• Cacao

Almost everyone consumes caffeinated beverages. Although it may vary depending on the manufacturer of these drinks, the average amount of caffeine in a 240 ml serving of the following drinks is as follows:

• Espresso: 240 – 720 mg
• Coffee Types: 102 – 200 mg
• Decaf Coffee: 2 – 12 mg
• Energy Drinks: 50 – 160 mg
• Tea: 40 – 120 mg
• Chocolate Milk: 2 – 7 mg
• Cacao Drinks: 2 – 7 mg

Some foods also contain caffeine. The most popular of these foods is chocolate. Dark chocolate, which has a high amount of cacao, also has a high caffeine content. 28 grams of dark chocolate contains between 5 and 35 mg of caffeine, on the other hand, the same amount of milk chocolate contains between 1 and 15 mg of caffeine. In addition, synthetically obtained caffeine is added to some medications, foods and beverages. This chemical is especially used as an active ingredient in some painkillers, cold remedies and weight loss supplements. However, synthetic caffeine can be found in energy drinks, many snacks, and even gum.

Is there Caffeine in Tea?

Caffeine is a substance found naturally in the leaves of the tea plant. Because of that, all brewed teas contain certain amounts of caffeine. However, there are some small details for this drink:

• You get more caffeine when you consume tea brewed in boiling water for longer periods of time. That’s because hot water and long brewing times allow more plant essence to be revealed.
• Tea contains L-theanine, an amino acid that contributes to calmness and relaxation. This amino acid works very well with caffeine, which helps you stay alert, helping you feel both relaxed and energetic.

In addition, the body processes caffeine in tea differently than it does in coffee and other drinks. Because tea contains an antioxidant called catechin. This molecule is also more difficult to digest by the body than normal caffeine. For this reason, it can be said that the focus-improving and vitalizing effects of caffeine in tea are felt later than in coffee. However, if you feel the effects of caffeine in tea later than in coffee, you can stay fit for longer hours. There is another interesting fact about tea. This information is that the catechin content varies according to tea types. For example; As green tea leaves are processed differently, the catechins in it are broken down less than the alternative. This causes green tea to be digested faster. For this very reason, green tea has similar effects to coffee.

What Are the Benefits Of Caffeine?

The main benefits of caffeine are that it increases energy levels and accelerates metabolism. The most well-known benefits of this substance, including its energizing effects, can be listed as follows:

• May Increase Your Energy Level: Caffeine increases energy as well as activating dopamine in the brain by blocking adenosine. This can be counted among the factors that contribute to increasing your energy^[4]. One study showed that those who did cycling exercise after drinking coffee increased the time they spent training by resting by 12 percent^[5].
• May Support Reducing the Risk of Type-2 Diabetes: There are studies showing that coffee helps maintain the function of beta cells in the pancreas, which are responsible for producing insulin to regulate blood sugar^[6]. A different review confirming these studies showed that people who consume one cup of coffee a day may have a lower risk of type-2 diabetes^[7].

• May Help Strengthen the Brain: Although not enough studies have been done yet to confirm, it has been shown that caffeine may help protect against neurodegenerative diseases such as Parkinson’s and Alzheimer’s. According to a study, people who consume caffeine daily have a significantly lower risk of developing Parkinson’s. Caffeine has been found to reduce the progression of Parkinson’s disease in the same study. Some studies conducted with nearly 30 thousand people have shown that people who consume coffee have a reduced risk of developing Alzheimer’s disease. In addition, studies have been conducted on the risk of dementia and cognitive decline, and the benefits of caffeine have been demonstrated by these studies^[10].
• May Accelerate Fat Burning: Caffeine’s ability to stimulate the central nervous system can speed up metabolism by up to 11 percent and fat burning by up to 13 percent^[11][12]. In other words, when you consume one cup of caffeine a day, you can spend approximately 70 extra calories.

Effect of Caffeine on Sports

Caffeine is also very beneficial for athletes as it is a powerful substance that can improve both physical and mental performance^[13]. Even a single cup can significantly improve focus and fat burning along with exercise performance^[14][15]. In particular, the following effects increase performance:

• Effect on Hormones: Adrenaline, which signifies “flight or fight,” is stimulated by caffeine. This helps to increase your performance^[16].
• Effect on Muscles: It can increase muscle performance through central nervous system activation^[17].
• Effect on Body Temperature: Caffeine has an effect that increases body temperature and helps you burn more calories^[18].

In a study with 12 participants, some were given caffeine for their body weight. In this study, participants worked out by doing bench press. It was observed that the performance of those who consumed caffeine increased compared to those who did not consume caffeine^[19].

What Are the Harmful Effects Of Caffeine?

Caffeine is actually a beneficial substance for the body. However, it has been observed that it can cause certain problems when consumed too much daily due to its stimulant effect. The most common caffeine harms can be listed as follows:

• Anxiety: Since caffeine blocks adenosine, which is the reason for feeling tired, and triggers adrenaline, it can make you feel anxious when you consume too much.
• Insomnia: The most distinctive feature of caffeine is that it helps people stay awake. However, too high caffeine intake can cause insomnia.
• Digestive Problems: Those who consume coffee frequently may notice that this drink speeds up bowel movements. This is believed to be the result of caffeine stimulating the muscles in the intestines^[20].
• Addiction: Despite all the benefits of caffeine, it cannot be denied that it can become a habit over time. However, it has been proven by scientific research that although it triggers brain chemicals, it does not cause addiction like other stimulant substances^[21].
• High Blood Pressure: Due to its stimulating effect on the nervous system, caffeine can increase blood pressure^[22]. However, it is known that the effect of caffeine on blood pressure is temporary. It also does not appear to have a very strong effect on people accustomed to consumption.
• High Pulse: Caffeine passes quickly through the stomach and small intestine and begins to stimulate the central nervous system when the first sip of coffee is taken. The receptors in the heart cells are also stimulated at this time and the heartbeat accelerates. As the heart beats faster, there is an increase in blood flow rate. The increase in heart rate caused by caffeine can take effect in as little as 15 minutes. The impact can take up to six hours to go away^[23].

For Whom Is Caffeine Harmful?

Caffeine can be consumed by anyone as long as it is controlled. However, it is important not to exceed the daily amount of caffeine required as it also has stimulating effects. If coffee especially is part of your daily routine, there is no problem in consuming it as long as it is a few cups. Even so, it is beneficial to keep coffee consumption under control in cases of high blood pressure, digestive sensitivity and anxiety disorders.

The Recommended Daily Dosage of Caffeine

For a healthy individual, 400 mg of caffeine per day seems safe^[24]. This amount roughly equals four cups of brewed coffee, 10 cans of cola, and two energy drinks. However, you should keep in mind that the amount of caffeine in drinks varies. Remember that you should cut back on your coffee intake if you are having issues like headaches, insomnia, trembling, fast heartbeat, or trembling in your muscles. If you still feel heart palpitations or other effects after drinking your morning coffee despite reducing the amount of caffeine, you can take the following precautions:

• There are decaffeinated coffee types. Although these are called “decaf” they contain very small amounts of caffeine. Since its amount is very small, your chance of experiencing palpitations decreases. You can also choose these coffee types.
• You can try caffeine-free herbal teas.
• You can consume fruit juices instead of soft drinks or energy drinks.