What are the contents of caffeine?

Caffeine is the most consumed and studied stimulant globally (2),(3).

Caffeine is present in many beverages, including tea and coffee. It has both beneficial and adverse effects on the health of humans.

It is important to note that the caffeine content may vary depending on the serving size, brewing time, or method in which it is prepared. Nevertheless, the caffeine content in coffee maybe twice that in an equal serving of tea.

Humans are advised to take 400 mg of caffeine per day. For example, an 8-ounce cup of coffee (240 ml) contains 95 mg of caffeine. On the other hand, an 8-ounce serving of black tea contains 47mg of caffeine (4, 5, 6).

Most studies on caffeine’s positive effects have been centered around coffee. However, it is essential to note that both beverages can provide immense health benefits despite varying amounts of caffeine.

Caffeine reduces the risk of some chronic diseases and improves mood, athletic performance, and mental alertness (7, 8, 9).

Caffeine stimulates the central nervous system. This explains its role as a performance-enhancing agent in sports (10, 11, 12).

Moderate caffeine intake appears to be protective against Alzheimer’s disease, dementia, non-alcoholic fatty liver disease, and metabolic syndrome (13, 14, 15, 16, 17).

Antioxidants

Antioxidants are essential. They protect the cells and tissues of the body against damages caused by free radicals, which may help inhibit the development of some chronic diseases (18).

Both coffee and tea are rich in antioxidants, primarily polyphenols. Polyphenols contribute to both beverages’ unique flavor and health benefits (19, 20, 21, 22).

There are several groups of polyphenols in coffee and tea. The ones present in black tea include thearubigins, theaflavins, and catechins. On the other hand, coffee contains chlorogenic acid and flavonoids (23, 24).

Coffee and tea have an energy-boosting effect

Coffee’s effect on energy

The caffeine in coffee is responsible for its energy-boosting effects.

Caffeine increases mental alertness and reduces fatigue. It achieves this by increasing the blood levels of dopamine and inhibiting adenosine (25).

Dopamine is responsible for coffee’s jittery effects. It increases the heart rate. Coffee also affects the brain’s reward system, which contributes to the addictive properties of coffee.

It is also important to note that adenosine promotes sleep. Caffeine blocks the sleep-promoting effect of adenosine and thus, reduces one’s feelings of tiredness.

Another point worth noting is that coffee boosts energy levels almost immediately.

99% of the caffeine in the coffee ingested is absorbed by your body within 45 minutes. However, peak blood concentrations may appear within 15 minutes after ingestion (26).

This explains why many people opt for a cup of coffee when they need that fast energy boost.

Tea’s effect on energy

Tea has lower caffeine content. However, it is rich in L-theanine. L-theanine is an antioxidant that stimulates the brain (27, 28).

Compared to caffeine, L-theanine may ease stress by increasing alpha waves in your brain. This increased production of alpha waves gives a calming and relaxing effect (29).

This counters caffeine’s arousing effect and helps you feel relaxed. However, your mental state remains alert.

Studies have shown that tea intake may maintain your focus, alertness, attention, and sharpness (30, 31).

Which is better between both?

Several studies have associated coffee with multiple side effects, including increased heart rate, heart failure, and high blood pressure. However, it is essential to note that moderate consumption of coffee is safe (32).

Although there are differences in their antioxidant compositions, tea and coffee are excellent sources of these essential compounds, protecting against some cancers and heart disease.

Other studies claim that coffee protects against liver cirrhosis, type 2 diabetes, and Parkinson’s disease. Tea, however, protects against kidney stones, cavities, and arthritis (1).

The caffeine content in coffee is higher than tea, which may be an advantage for people who want an instant burst of energy. But, on the other hand, it may cause poor sleep and anxiety in sensitive people (8).

It is also important to note that high coffee intake may result in addiction or dependence (33).

If you are very sensitive to caffeine, you’re better off with tea. Tea contains L-theanine. L-theanine is an amino acid that calms and helps you relax while maintaining a high level of alertness.

You can also choose the decaf variant of both beverages or herbal tea, caffeine-free. These have their unique benefits.