The caffeine content of tea and coffee varies depending on the type of tea leaves and coffee beans used. However, coffee contains higher caffeine levels than tea.
Caffeine is a stimulant derived from seeds of the cocoa plant, and is commonly found in the following:
- Coffee (brewed, espresso, cappuccino)
- Tea (black tea, green tea, herbal tea, white tea, oolong tea)
- Other beverages (energy drinks, soft drinks)
- Certain medications
Caffeine, once consumed, is quickly absorbed from the gut and reaches the bloodstream, which then stimulates the brain and central nervous system by increasing the secretion of hormones, such as dopamine and noradrenaline, that gives us energy.
Because of its stimulant action, caffeine is used by almost 80 percent of the world's population daily. The most commonly consumed caffeinated beverages are tea and coffee, although tea contains less caffeine than coffee.
How much caffeine does tea/coffee have?
The amount of caffeine in tea significantly varies depending on the type of tea and the tea leaves used. Similarly, the caffeine content of coffee depends on the beans used and the brewing process.
Below is a table that compares the caffeine content of different tea and coffee beverages.
The longer the tea leaves are heated in warm water, the higher caffeine levels steep into the prepared cup.
Similar to tea, the longer the coffee beans are brewed, the higher the caffeine levels become.
Recommended daily intake of caffeine
The recommended dose of caffeine for healthy adults is less than 400 mg/day, which equals about four cups of coffee. As stated before, since the caffeine content is lower in tea, about two cups of tea equals one cup of coffee, making it possible to drink up to eight cups of tea each day.
For pregnant and lactating mothers, it is less than 200 mg/day (about two cups of coffee or four cups of tea).
What are the benefits of caffeine?
Some of the benefits of caffeine include:
- Enhancement of mood and alertness: This is due to decreased levels of hormones, such as adenosine, that promote fatigue.
- Boosts metabolism: This is because of its stimulant action on the central nervous system that causes an increased fat-burning effect in the body.
- Increased energy levels leading to better performance: This is because of better levels of adrenaline and noradrenaline.
- Protection against diabetes and heart disease (as seen in many research studies): This may be because of its antioxidant effect.
- Skin/liver protection: It gives mild protection against skin cancer due to its antioxidant effect.
In addition to these benefits, green tea, black tea and white tea all offer their own benefits, such as boosting your immune system, fighting off inflammation and warding off cancer and heart disease.
What are the side effects of caffeine?
Side effects of excessive caffeine intake include:
- One of the most prized qualities of caffeine is its ability to reduce sleepiness.
- When consumed in large quantities, regular doses can interfere with the normal sleep cycle of a person, thus leaving them more fatigued than before.
- Anxiety and agitation
- Caffeine reduces the amount of adenosine, which is the tiring hormone and promotes the secretion of dopamine and noradrenaline that helps stimulate the central nervous system.
- Moreover, it hyperstimulates the brain system causing anxiety and agitation.
- Caffeine is a highly addictive substance; thus, it shouldn’t be consumed in high doses regularly.
- Because of its stimulating action on our body, our system gets used to this daily stimulant.
- Suddenly stopping coffee may result in various withdrawal symptoms such as increased agitation, sleeplessness and headache.
- This is again due to hyperstimulation of the brain system leading to anxiety and nervousness.
- This only happens as a rebound effect of large caffeine consumption.
- Caffeine has its maximum effect on alertness and focus, followed by a slag.
- High blood pressure
- This is due to the stimulation effect of noradrenaline released, causing a spike in blood pressure.
- Frequent urination
- This occurs due to stimulation of the urinary bladder because of caffeine, causing the person to frequently visit the bathroom.
- Digestive problems
- Most people like to consume their tea or coffee early in the morning on an empty stomach for its rapid absorption and action. However, this regularly can alter the stomach pH and can lead to ulcers.
Going completely caffeine-free is not necessarily the healthiest option. However, limiting your caffeine intake can help you gain the benefits of the stimulant while avoiding the adverse effects. That said, for a caffeine-free beverage, consider drinking herbal teas from the Camellia Sinensis plant.