What is caffeine, is it beneficial to your health? Read this article to find out
Caffeine is a psychoactive substance that occurs naturally in coffee. Billions of people rely on caffeine to wake up or to get through that busy night or tiredness in the afternoon. It is one of the most commonly used natural stimulants in the world today holding a lot of benefits as well as a few negative effects that most times apply to overconsumption.
How does caffeine work?
Caffeine is a natural stimulant commonly found in tea, cocoa plant, and coffee that works by stimulating the brain and central nervous systems helping you stay alert and prevent the beginning of tiredness.
Once caffeine is consumed, it is quickly absorbed from the alimentary canal into the bloodstream. It then travels to the liver where it is broken down into compounds that can affect the function of the various organs. Caffeine’s main effect is on the brain, it blocks the effects of adenosine, a neurotransmitter that relaxes the brain and makes you feel tired. Adenosine levels on a normal basis build up over the day making you increasingly more tired and very sleepy.
Caffeine helps you stay awake by connecting to adenosine receptors in the brain without activating them. This act blocks the effects of adenosine leading to reduced tiredness.
Caffeine also increases blood adrenaline levels and increases brain activity of the neurotransmitters dopamine and norepinephrine.
A combination of this further stimulates the brain and promotes a state of arousal, focus, and alertness. Because it affects your brain, caffeine is often referred to as a psychoactive drug.
Drinks and foods containing caffeine
Caffeine is naturally found in the nuts, leaves, or seeds o certain plants. These natural sources are then processed to produce caffeinated foods and beverages.
The following beverages contain caffeine in the following amount per 8- ounce (240ml) serving;
- Coffee 102 – 200mg
- Yerba mate 65 – 130mg
- Energy drinks 50 – 160mg
- Brewed tea 40 – 120mg
- Espresso 240 – 720mg
- Soft drinks 20 – 40mg
- Decaffeinated coffee 3 – 12mg
- Chocolate milk 2 – 7mg
- Cocoa beverage 2 – 7mg
28 grams (1 ounce) of milk chocolate contains 1 – 15mg of caffeine whereas 1 ounce of dark chocolate has 5 – 13.5mg.
Benefits of caffeine
Caffeine may also provide several health benefits together with its stimulating effects.
- Promotes fat loss and boosts metabolism: Caffeine may increase metabolism by 11% and fat burning by 13% because of the inability to stimulate the central nervous system.
Consuming 300mg of caffeine per day may allow you to burn an extra 79 calories daily. This amount may seem small but it’s similar to the calorie excess responsible for the average yearly weight gain of 2.2. Pounds (1kg) in Americans.
- Promotes brain and mood function: Caffeine connects to the adenosine receptors in the brain and ends up blocking the brain signaling molecule adenosine. This produces a relative increase in other signaling molecules such as dopamine and norepinephrine. The effect is this change in brain messaging is thought to benefit your mood and brain function.
A review on this showed that after participants ingested 37.5 – 450mg of caffeine, they had improved alertness, short-term recall, and reaction time.
Another study linked drinking 2 -3 cups of caffeinated coffee (providing about 200 – 300mg caffeine) per day to a 45% lower risk of suicide.
Caffeine has also been reported to lower the risk of depression in caffeine consumers by 13%.
Drinking between 3- 5 cups of coffee per day or more than 3 cups of tea per day may also reduce the risk of brain diseases such as Alzheimer’s and Parkinson’s by 28 – 60%.
- May guide against heart disease and Diabetes: Caffeine has been proven to lower the risk of heart disease in men and women who drink between 1-4 cups of coffee daily (providing approximately 100-400mg of caffeine) by 16- 18%
Other studies show that drinking 2-4 cups of coffee or green tea per day is linked to a 14-20% lower risk of stroke.
Although caffeine may slightly raise blood pressure in some people, the effect is generally small and tends to fade for most individuals when they consume coffee regularly.
Caffeine also protects against diabetes. A review noted that those who drink the most coffee have up to a 29% lower risk of developing type 2 diabetes. Similarly, those who consume the most caffeine have up to a 30% lower risk.
- Protects the liver: Coffee may also reduce the risk of liver damage (cirrhosis) by as much as 84%. It may slow disease progression, improve treatment response and lower the risk of premature death.
A 2019 review of existing literature found that consuming a moderate amount of caffeine has a protective effect against liver cancer.
- May enhance exercise performance: Caffeine may increase the use of fat as fuel when it comes to exercise. This is beneficial because it can help the glucose stored in the muscles last longer, automatically delaying the time it takes your muscles to reach exhaustion.
Researchers observed that doses of 2.3mg per pound (5mg per kg)of body weight improved endurance performance by up to 5% when consumed 1 hour before exercise.
Side effects of caffeine
Studies have been able to prove that consuming caffeine in low-to-moderate amounts is considered safe. Although caffeine consumption can be addictive.
The side effects associated with caffeine occur when caffeine is consumed in significantly high doses. Research has shown that your genes have a major role to play in your tolerance to caffeine. Some people can consume more volume of caffeine than others without experiencing negative effects.
Some of the side effects linked to consuming a high dose of caffeine include; Anxiety, insomnia, digestive issues, addiction, high blood pressure, rapid heart rate.
Recommended dosage for caffeine
The US Department of Agriculture (USDA) and the European Food Safety Authority (EFSA) consider a daily intake of 400mg of caffeine to be safe. This amounts to 2-4 cups of coffee per day.
According to the American College of Obstetricians and Gynecologists, pregnant women should limit their daily intake to 200mg.
Fatal overdose of caffeine had been reported with single doses of 500mg of caffeine. Therefore, it is recommended to limit the amount of caffeine you consume at once to 200mg per dose.