Although black tea, espresso, and coffee are known for their high caffeine content, green tea  also contains a notable, though moderate, amount of caffeine. The caffeine levels in white teas can vary significantly, while herbal teas are generally free from caffeine. This unique compound, caffeine, has gained unmatched popularity as a natural stimulant and can be found in over 60 different plant species. It’s enjoyed worldwide, particularly in beverages like coffee, chocolate, and various types of tea. The amount of caffeine present in a drink is influenced by the choice of ingredients and the method of preparation used. Although caffeine is largely regarded as safe for consumption, excessive intake may lead to certain health concerns. In this article, we will compare the caffeine content across different teas and coffees, guiding you on which beverage might be the best choice for your needs.

Why Should We Be Cautious About Caffeine?

A staggering 80% of the global population indulges in caffeinated beverages on a daily basis. From coffee to tea, these drinks have become an integral part of many cultures, including the rich traditions of India (chai), the vibrant café culture in Australia, and the ceremonial tea practices in Japan. The U.S. Department of Agriculture (USDA) and the European Food Safety Authority (EFSA) both advocate for a safe daily caffeine intake of up to 400 mg, which can be broken down to 200 mg per single serving or 1.4 mg per pound (around 3 mg per kg) of body weight.

Caffeine's stimulating properties are often celebrated for their potential health benefits, such as heightened alertness, improved athletic performance, an uplifted mood, and a boost in metabolism. In moderation, it can be a valuable part of a balanced lifestyle. However, it is essential to recognize that excessive consumption—particularly doses exceeding 500 mg at once—can lead to various health concerns. High doses of caffeine have been linked to increased anxiety, restlessness, and challenges with sleep. Moreover, some studies indicate that even moderate caffeine intake can lead to chronic headaches and migraines over time.

Additionally, caffeine has the potential to be mildly addictive, with certain individuals being more prone to developing a dependency. While caffeine is a widely enjoyed stimulant found in numerous foods and beverages, including coffee and tea, it's critical to consume it mindfully to avoid adverse effects.

Caffeine Content Varies by Beverage Type and Method of Preparation

The caffeine levels found in tea or coffee can differ greatly based on the drink's origin, variety, and how it is prepared. Tea leaves generally contain around 3.5% caffeine, while coffee beans range between 1.1% and 2.2%. However, the brewing process for coffee typically utilizes hotter water, which extracts a higher amount of caffeine from the beans. Additionally, the quantity of coffee beans used is usually greater than that of tea leaves for a single serving. As a result, a standard cup (237 ml) of brewed coffee commonly contains more caffeine than a comparable cup of tea.

Tea Varieties

Black, green, and white teas are all derived from the same plant, Camellia sinensis. The key differences between these teas lie in the timing of the harvest and the extent of oxidation the leaves undergo. Black tea leaves undergo full oxidation, while white and green tea leaves do not, imparting a distinct bold and sharp flavor to black tea.

An average cup (237 ml) of black tea contains approximately 47 mg of caffeine, with some variations reaching up to 90 mg. In contrast, green teas provide between 20–45 mg, while white teas yield about 6–60 mg per cup (237 ml). Matcha green tea, which is typically sold in powdered form, is another tea variety with higher caffeine content, delivering around 35 mg of caffeine in a half-teaspoon (1-gram) serving. Similarly, yerba mate, a traditional South American tea made by steeping the twigs and leaves of the Ilex paraguariensis plant, usually contains about 85 mg of caffeine per cup (237 ml). Although not made from traditional tea leaves, herbal teas serve as an excellent caffeine-free option.

Tea Preparation

The method of preparation plays a crucial role in determining the caffeine content of tea. Teas that steep for longer durations and in hotter water tend to yield a stronger cup. For instance, a mug of Tazo Earl Grey contains about 40 mg of caffeine after steeping for just 1 minute in 6 ounces (177 ml) of water heated to 194–203°F (90–95°C). This caffeine level increases to 59 mg after steeping for 3 minutes. In comparison, Stash Green Tea contains 16 mg of caffeine after 1 minute of steeping under the same conditions, rising to 36 mg after 3 minutes.

Coffee Varieties

An average 8-ounce (237 ml) cup of coffee typically contains around 95 mg of caffeine. There is a widespread belief that coffee brewed from dark-roasted beans has higher caffeine content than that from light-roasted beans. However, since roasting does not significantly alter caffeine levels, this may not hold true. Nevertheless, dark roast coffees are less dense than their light roast counterparts, meaning you may need to use more beans or grounds when brewing, resulting in higher caffeine levels per cup.

Espresso serves as a concentrated source of caffeine. For example, a “single” espresso shot from Starbucks contains about 58 mg of caffeine per 1-ounce (30 ml) serving. Many specialty coffee drinks, including lattes and cappuccinos, use a double shot of espresso, which amounts to 116 mg of caffeine. Among decaffeinated options, decaf espresso typically has the highest caffeine content, ranging from 3–16 mg per 16-ounce (473 ml) serving, while decaf coffee usually provides less than 3 mg per 8-ounce (237 ml) cup. Decaffeinated teas generally fall somewhere in between these two types of coffee.

Coffee Preparation

Hot water effectively extracts more caffeine from tea leaves in a shorter time frame, and this principle is equally applicable to coffee. Coffee is generally brewed at temperatures between 195–205°F (90–96°C). An alternative method is cold-brewing, which involves soaking ground coffee in cold, filtered water for a period of 8–24 hours. This technique requires approximately 1.5 times more ground coffee compared to standard hot-water brewing, potentially resulting in a more caffeinated cup. Overall, the caffeine content can fluctuate significantly based on the type and preparation methods of tea and coffee, with black teas and espresso containing the highest amounts, while herbal teas and decaffeinated options have minimal caffeine levels.

Which Beverage Should You Choose?

Caffeine has a rapid effect, typically manifesting within 20 minutes to an hour after consumption. For those who are sensitive to its stimulating effects, it is advisable to opt for teas that are lower in caffeine, such as white tea  or herbal tea. Alternatively, brewing high-caffeine teas for a shorter duration, such as just 1 minute instead of the usual 3, can help moderate your intake. Another excellent option for enjoying your favorite beverages without significant caffeine is to choose decaffeinated tea , coffee, or espresso. On the other hand, if you relish beverages with a higher caffeine content, you might appreciate espresso, cold-brew coffee, and teas that are richer in caffeine, like green tea and black tea .

To maintain caffeine consumption within safe limits, it is recommended to keep it under 400 mg per day, or limit yourself to 200 mg of caffeine at any one time. This means you should ideally consume no more than three to five 8-ounce (237 ml) cups of regular coffee daily, or up to eight 1-ounce (30 ml) shots of espresso.

Individuals with heart conditions, those susceptible to migraines, and people on specific medications should be particularly cautious and limit their caffeine intake. Pregnant or breastfeeding women should also adhere to a limit of no more than 200 mg of caffeine per day, which equates to approximately one 12-ounce (355 ml) cup of coffee or up to four 8-ounce (237 ml) mugs of long-brewed black tea. If you're worried about your caffeine consumption, consider selecting white tea or herbal tea, along with decaffeinated coffee. For those who enjoy caffeine, strive to keep your intake below 400 mg or about 4 cups of coffee daily, with an aim for no more than 200 mg of caffeine at once.

The Bottom Line

The manner in which you brew your tea and coffee significantly influences their caffeine levels. If you're looking to reduce your caffeine intake, consider steeping your tea for a shorter duration, and choose decaffeinated options for your preferred coffee and espresso beverages. On the other hand, if you relish the stimulating effects of caffeine, strive to keep your daily consumption below 400 mg.