Though green tea and coffee both offer health benefits due to their caffeine and antioxidant content, coffee has more than three times the amount of caffeine.
Tea is the world’s most frequently consumed beverage after water. Coffee is also incredibly popular (1, 2).
In the United States, more than 85% of adults consume caffeine regularly, with an average daily intake of 180 mg, which is the amount of caffeine in about 2 cups of coffee (2).
People consume green tea and coffee for their characteristic taste and health benefits.
You may enjoy a cup of coffee by brewing roasted and ground coffee beans, while you can prepare green tea by steeping the unfermented leaves of the Camellia sinensis plant, also known as the tea plant (1).
This article compares the benefits and downsides of coffee and green tea, as well as healthy and less healthy ways to prepare them.
Share on PinterestCaffeine content
Caffeine is the most widely consumed stimulant drug worldwide, and it’s naturally found in coffee and tea. In fact, coffee and tea are often the most predominant sources of caffeine in a person’s diet (2, 3, 4).
However, coffee provides more than three times the amount of caffeine than green tea. An 8-ounce (240 mL) serving of coffee provides 96 mg of caffeine, while the same amount of green tea provides 29 mg (5, 6).
According to research, intakes of 400 mg of caffeine per day are considered safe for adults. However, the recommended limit drops to 100 mg per day for teenagers and 2.5 mg/kg per day for children (2).
Caffeine is one of the most studied substances, due to its multiple beneficial health effects. These include (4, 7, 8, 9, 10):
- increased energy levels, alertness, attention, and wakefulness
- lowered mental and physical fatigue
- quickened reaction times and improved accuracy
- enhanced exercise performance
- improved memory and mood
Evidence also suggests caffeine has protective effects on brain health, reducing the risk of dementia and other degenerative diseases (11, 12, 13).
Some studies have even linked caffeine intake with a lowered risk of developing type 2 diabetes (14, 15, 16).
However, research on caffeine and diabetes seems inconclusive, and further evidence suggests that it may actually increase blood sugar levels (17, 18).
Scientists need to do more research on the potential effects of caffeine.
SummaryCaffeine is a stimulant drug naturally found in coffee and tea. However, coffee provides about three times the amount of caffeine as green tea.
Health benefits
Green tea and coffee have multiple health benefits in common, including their high antioxidant content and weight loss effects.
Great antioxidant sources
Free radicals play numerous beneficial roles in your body. However, in excess, they lead to oxidative stress.
Oxidative stress is a harmful process that can negatively affect your health by causing disease and speeding up the aging process (19).
Luckily, coffee and green tea are loaded with antioxidants — compounds with beneficial effects against oxidative stress.
They’re both particularly rich in a group of antioxidants called polyphenols. In both drinks, these are responsible for many of their benefits and flavor (20).
Epigallocatechin gallate (EGCG) and chlorogenic acid (CGA), are the most abundant polyphenols in green tea and coffee, respectively. Studies in test tubes, animals, and humans suggest they may have potent anticancer effects (21, 22, 23).
For instance, EGCG may hinder tumor growth and spread, and it may lead to tumor cell death (24, 25, 26).
Its anti-inflammatory effect may help prevent the chronic inflammation involved in the onset of cancer (21).
On the other hand, CGA appears to inhibit tumor growth and promote cancer cell death (21, 23).
Studies suggest that EGCG in green tea may have a beneficial effect against cancer cells in head and neck tumors, as well as in lung, prostate, breast, colorectal, and pancreatic cancer cells (21, 26).
In contrast, coffee’s CGA may have beneficial effects against liver, endometrial, and skin cancers (21).
Additionally, CGA may also benefit heart health and blood sugar control by regulating blood triglyceride levels and improving how your cells respond to the hormone insulin (23, 27, 28).
Weight loss effects
Coffee’s CGA and green tea’s EGCG, together with caffeine, provide both drinks with weight loss properties.
Animal studies show that CGA may lower insulin, blood cholesterol, and triglycerides in the blood, as well as reducing weight and visceral fat (29).
Visceral fat is the fat stored inside the abdomen around the organs. It’s linked to an increased risk of heart disease and diabetes (30).
Similarly, animal studies show that EGCG also leads to weight loss and reduced visceral fat by promoting fat breakdown (31).
It also helps promote the growth of beneficial bacteria in the gut, which help burn fat and improve insulin sensitivity, among other beneficial effects (31, 32, 33).
Furthermore, studies have found that caffeine is associated with weight loss. It appears to (34, 35):
- reduce hunger
- increase calorie burning
- activate a type of fat called brown adipose tissue (BAT), whose quantities decrease as you age
BAT has the potential to produce large amounts of heat and modulate fat and glucose metabolism (35, 36).
L-theanine in green tea may be calming
L-theanine is an amino acid naturally present in tea, including green tea. This compound is known to affect the brain, increasing feelings of calm alertness (37).
One study gave about the same amount of L-theanine to participants as they might consume in 6.8 ounces (200 mL) of tea, or about one serving. The participants who drank the L-theanine had more alpha brainwave activity, which indicates a calm, alert mental state (37).
Certain reduced health risks
Evidence shows that green tea is associated with a reduced risk of stroke, diabetes, and depression (38).
Meanwhile, coffee is linked to reduced heart disease mortality (38).
SummaryCoffee and green tea are loaded with antioxidants that provide anticancer properties. They may also help you lose weight. L-theanine in green tea may promote a calm, alert mental state.
Potential downsides
Though both coffee and green tea are known for their benefits, they may also have some drawbacks.
On one hand, added ingredients — such as sweeteners, creamers, and flavored syrups — may significantly increase your coffee or tea’s calorie and sugar count.
Research shows that sweetened coffee and tea are among the foods that contribute to high sugar intake in U.S. adults. This is associated with weight gain, type 2 diabetes, heart disease, and dental cavities (39, 40).
On the other hand, even though caffeine is considered a beneficial drug, consuming too much of it may lead to unwanted side effects, such as caffeine-induced anxiety and sleep disorders (41).
Evidence suggests that chronic intakes of caffeine may lead to increased alertness and anxiety. If consumed in high doses of over 400 mg per day, it can worsen symptoms of anxiety, panic disorder, and insomnia (13, 41, 42).
Furthermore, caffeine use may lead to caffeine dependence in some people. Those who have caffeine dependence may have caffeine withdrawal and may continue to use caffeine despite experiencing harmful effects (41, 43).
There’s evidence that oils naturally present in coffee, including cafestol and kahweol, may increase blood cholesterol levels (44).
An analysis of studies found that consuming coffee made without a paper filter was associated with increased total and LDL (bad) cholesterol in the blood (44).
However, the authors found that people’s cholesterol levels didn’t rise when they drank coffee that was made using a paper coffee filter (44).
SummaryConsuming too much caffeine is one potential downside of coffee and green tea, and may come with several detrimental effects. Regularly adding sugar to your coffee or tea may also lead to health issues.
Preparation tips
Coffee and green tea may provide multiple health benefits. However, the way you prepare them can make the difference between a nutritious or less nutritious beverage.
Follow these tips to brew a healthy cup:
- Use a coffee filter. Paper filters help reduce the amount of cafestol from coffee, which is linked to increases in blood cholesterol levels (44, 45, 46).
- Switch your full fat milk or creamer to low fat milk. Making this simple change will help reduce your drink’s total calorie and fat content.
- Skip the sugar. Adding too much sugar, honey, syrups, or other sweeteners to your coffee or tea may turn them into less nutritious drinks.
- Add cinnamon or nutmeg to your coffee. Instead of using sugary syrups for flavor, add cinnamon or nutmeg to your coffee. These spices may help prevent and treat type 2 diabetes and obesity (47, 48, 49, 50).
- Add lemon juice to your tea. Test tube and animal studies show that adding lemon juice to your green tea may make its antioxidants more available to your body (51, 52).
You may make a healthier cup of coffee or tea just by avoiding added sugars and full fat milk or creamers or by adding ingredients like cinnamon, cardamom, and lemon juice.
Which is better?
Green tea and coffee are both safe beverages that provide you with the benefits of caffeine and antioxidants. Both are also associated with a decreased risk of certain diseases.
However, people with anxiety, insomnia, and panic disorders should consider choosing green tea over coffee due to its lower caffeine content and because it contains L-theanine — an amino acid that promotes a state of calm alertness (53, 54).
Coffee’s higher caffeine content may more easily lead to caffeine dependence compared with that of green tea.
On the flip side, coffee would be a more suitable choice if you’re looking for increased alertness or improved physical performance (4, 55).
Determining which is better ultimately comes down to your specific needs.
SummaryGreen tea and coffee are both healthy and safe. Green tea may be a better choice for people with anxiety or insomnia. In contrast, coffee may suit you better if you’re looking for increased alertness or improved physical performance.
The bottom line
Green tea and coffee are two healthy staple drinks in many people’s diets.
They share many health benefits, such as anticancer effects and weight loss properties due to their caffeine and antioxidant content.
They also share the potential downsides associated with commonly added ingredients, such as sugar, creamers, and flavored syrups.
Considering coffee’s higher caffeine content and green tea’s L-theanine content may help you decide which one is better for you.