How Many Calories in Green Tea

Green tea is one of the most popular beverages worldwide, known for its light, earthy flavour and association with health benefits ranging from improved metabolism to antioxidant protection. While often praised as a zero-calorie drink, that’s only true under certain conditions. The calorie content of green tea depends on how it's prepared and what’s added to it. Whether you're drinking it plain or with sweeteners, it’s worth knowing exactly what you're consuming.

Calories in Green Tea by Preparation and Additions

A plain cup of brewed green tea, made from tea bags or loose leaves and water, contains zero to two calories per 240ml cup. These negligible calories come from trace amounts of protein or carbohydrates naturally found in tea leaves.

However, green tea becomes significantly more calorific when served with added sugar, honey, milk or syrup. A cup with one teaspoon of sugar adds about 16 calories, while a tablespoon of honey contributes around 60 calories. Green tea lattes or bottled green teas often include sweeteners and flavourings, and these can range anywhere from 30 to over 150 calories per serving, depending on brand and portion size.

If you're drinking green tea for its health properties, keeping it plain or using a calorie-free sweetener is the best way to avoid hidden energy intake.

Nutritional Breakdown of Green Tea

In its pure form, green tea contains virtually no fat, carbohydrates or protein. It’s made by steeping unoxidised tea leaves in hot water, which releases antioxidants, caffeine and small amounts of minerals. A standard serving includes around 25 to 35 milligrams of caffeine, depending on the type and steeping time.

The standout nutritional features of green tea are its polyphenols, particularly catechins like EGCG (epigallocatechin gallate), which have antioxidant and anti-inflammatory properties. These compounds help protect the body from oxidative stress, support heart health, and may aid in metabolic regulation.

Green tea also contains L-theanine, an amino acid that promotes calmness and focus, often balancing the stimulating effect of caffeine.

Benefits of Drinking Green Tea

Green tea is widely considered a health-promoting beverage, thanks to its high content of antioxidants and bioactive compounds. Regular consumption has been linked to improved brain function, fat oxidation, reduced risk of certain cancers, and better cardiovascular health.

It’s also thought to boost metabolism, particularly in combination with caffeine, which can increase energy expenditure and fat burning in some individuals. For people looking to lose weight, substituting green tea for sugary drinks can help lower daily calorie intake while providing beneficial compounds.

Green tea is hydrating, especially when consumed without diuretics or excess caffeine, and can be sipped throughout the day with minimal impact on blood sugar or caloric intake.

Downsides of Drinking Green Tea

While green tea is generally safe and healthy, it’s not without its downsides. Drinking large amounts especially more than five to six cups per day can lead to caffeine-related side effects such as insomnia, jitteriness or increased heart rate, particularly in sensitive individuals.

It can also interfere with iron absorption from plant-based foods due to its tannin content. To minimise this effect, it’s best to drink green tea between meals rather than with food if you have concerns about iron levels.

Bottled green teas, sweetened variants and green tea lattes can be misleadingly high in sugar and calories, which negates the benefits of plain brewed tea. Always check labels if you're buying ready-made options.

How Green Tea Fits Into Your Diet

Green tea can be a valuable daily addition to a healthy diet, particularly when used in place of sugary or high-calorie drinks like soft drinks, juice or flavoured coffees. Because it’s naturally low in calories and carbs, it fits well into weight loss, low-carb, and blood sugar-conscious diets.

It also supports hydration and makes a great zero-calorie drink option between meals. Whether hot or iced, green tea can be enjoyed without concern for energy intake when brewed plain.

For those aiming to maximise the antioxidant content, freshly brewed loose-leaf green tea or high-quality tea bags are ideal. Powdered matcha a concentrated form of green tea contains more antioxidants and caffeine, and thus more calories, but still remains low overall at around 3 calories per gram of powder before additives.

Glycaemic Index of Green Tea

Plain green tea has a glycaemic index of zero, meaning it does not raise blood sugar levels. It contains no digestible carbohydrates and is therefore a safe and beneficial beverage for those with diabetes, insulin resistance, or anyone trying to manage blood glucose levels.

Sweetened green teas or those made into lattes can have a much higher glycaemic load, especially when prepared with syrups or sugar. Choosing unsweetened varieties ensures you get the metabolic benefits without unwanted blood sugar spikes.

How Green Tea Is Made and What It Contains

Green tea is made from the Camellia sinensis plant. Unlike black tea, green tea leaves are lightly steamed or pan-fired to prevent oxidation, which helps preserve their green colour and antioxidant profile. The leaves are then dried and packaged for use in loose-leaf form, tea bags or powdered matcha.

Green tea contains caffeine, L-theanine, polyphenols, and catechins, which work together to promote focus, reduce inflammation and support general wellbeing. Flavoured green teas may contain added herbs, flowers or fruits, but the base nutritional profile remains largely unchanged if no sugar is added.

Healthy Alternatives to Green Tea

If you're looking for a low-calorie, antioxidant-rich beverage, white tea and herbal teas such as rooibos, peppermint or chamomile make excellent alternatives. Black tea offers a stronger flavour with slightly more caffeine, while oolong tea sits between green and black in both taste and strength.

For something cold, infused water with lemon, cucumber or mint provides hydration with no calories, while sparkling water with a splash of fruit juice can be a refreshing substitute for sweetened drinks.

Summary

Plain green tea contains virtually zero calories, making it one of the healthiest drinks you can consume. Its benefits go well beyond its low energy content, with antioxidants, polyphenols and mild caffeine offering support for metabolism, focus and long-term health. However, added sugar, honey or milk can significantly raise the calorie content, so it's best consumed plain if you’re watching your intake. Whether hot or iced, green tea is an excellent low-calorie choice to include in a balanced diet, offering hydration and health benefits with no dietary drawbacks.