How Many Calories in a Cup of Tea

A plain cup of tea is one of the lowest calorie drinks you can have, but once you add milk or sugar, the numbers start to shift. On its own, a standard cup of black tea contains less than 5 calories. It’s virtually calorie-free, making it a popular choice for those watching their intake. However, a splash of milk and one or two teaspoons of sugar can push a single cup into the 30 to 50 calorie range, depending on how it's made.

Calories Based on Ingredients and Add-Ons

A typical cup of tea brewed with a tea bag and hot water contains negligible calories. There are no carbohydrates, fats, or proteins unless you start adding extras. A small amount of semi-skimmed milk adds around 10 to 15 calories, while full-fat milk contributes slightly more. Each teaspoon of sugar adds approximately 16 calories, so two sugars and a splash of milk can bring a basic brew to over 45 calories per cup. Herbal teas, like chamomile or peppermint, are also extremely low in calories if served plain.

If you’re drinking chai, bubble tea, or other sweetened milk teas, the calorie content can increase dramatically. A traditional Indian masala chai with whole milk and sugar might contain over 100 calories per cup, while commercial milk tea drinks can easily reach 200 to 300 calories, especially when made with syrups or toppings like tapioca pearls.

Nutritional Breakdown

Plain black or green tea contains minimal macronutrients. The nutritional value comes primarily from antioxidants such as catechins and theaflavins, which may support heart health and reduce inflammation. Tea also contains a small amount of caffeine, typically around 30 to 50 milligrams per cup, depending on the type and steeping time. Adding milk introduces small amounts of calcium, vitamin D, and fat, while sugar contributes pure carbohydrates with no nutritional benefit.

Health Benefits of Tea

Tea is rich in bioactive compounds that may promote overall health. Regular consumption of black or green tea has been linked to improved heart health, lower cholesterol, better brain function, and even reduced cancer risk. Tea is hydrating, especially when consumed without added sugar, and the presence of polyphenols can aid digestion and provide a mild metabolic boost. Herbal teas often offer additional benefits such as calming effects from chamomile or digestive support from peppermint, without any added calories.

Downsides of Tea

Tea on its own has few downsides, but problems arise with how it’s often served. High sugar content in sweetened teas can contribute to weight gain, blood sugar spikes, and increased risk of insulin resistance if consumed regularly. Some people may also experience sensitivity to caffeine, which can lead to restlessness, headaches, or sleep disruption. Tannins in black tea can slightly reduce iron absorption if consumed in large quantities, especially when taken with meals. Tea with full-fat milk and sugar can become a hidden source of excess calories in your daily routine.

How Tea Affects Your Diet

When consumed plain, tea is one of the most diet-friendly beverages available. It adds virtually no calories, supports hydration, and can help satisfy cravings without spiking blood sugar. However, milk and sugar turn it into a small but consistent source of additional energy. Drinking multiple cups a day with sugar can quietly increase your calorie intake by 100 to 200 calories daily, enough to impact weight management over time. If you’re trying to lose or maintain weight, switching to unsweetened tea or using low-fat milk alternatives can help keep your intake in check without sacrificing flavour.

Glycemic Index (GI) Rating

Tea by itself has a glycemic index of zero, meaning it doesn’t raise blood sugar. When sugar is added, however, the GI of the drink changes. A cup of sweetened tea has a moderate glycemic impact, depending on the amount of sugar used. Milk also contributes some natural lactose, a sugar that can raise blood glucose slightly. For individuals with diabetes or insulin resistance, unsweetened tea or those sweetened with non-caloric alternatives like stevia are better options.

How Tea is Made

Tea is made by steeping the dried leaves of the Camellia sinensis plant in hot water. The type of tea, whether it’s black, green, oolong, or white depends on how the leaves are processed after harvesting. Black tea is fully oxidized, giving it a bold flavour and dark colour. Green tea is unoxidized and retains more of its natural antioxidants. Herbal teas, technically not true teas, are made by steeping herbs, flowers, or fruit in hot water and do not contain tea leaves or caffeine.

Ingredients in a Cup of Tea

A plain cup of tea contains just water and tea leaves. Once you add milk, the ingredients expand to include water, tea, and dairy or plant-based alternatives such as oat, soy, or almond milk. Adding sugar or sweeteners increases the calorie count and changes the nutritional profile, introducing simple carbohydrates without additional nutrients.

A Healthier Alternative

If your daily tea habit includes multiple spoons of sugar and whole milk, there are simple swaps that make it healthier. Using unsweetened almond or oat milk cuts the calories while keeping the creamy texture. Replacing sugar with stevia or simply cutting back gradually reduces calorie load without dramatically changing the taste. Herbal teas are another low-calorie option with added functional benefits for digestion, sleep, or immune support and don’t require milk or sugar to taste good.

Does Tea Break a Fast?

For those practicing intermittent fasting, plain tea is considered safe and doesn't break a fast because it contains negligible calories. However, once you add milk or sugar, the calorie content climbs above fasting thresholds. Even a small splash of milk can interrupt autophagy or the insulin-sensitive state, depending on your fasting goals. If you're fasting for fat loss or metabolic health, stick to plain black, green, or herbal teas with no additives.

Cultural Differences in Tea Calorie Content

In the UK, a standard cup of tea usually includes a splash of milk and possibly sugar, pushing it toward the 30–50 calorie mark. In the US, iced tea is more common and often heavily sweetened. A glass of sweet iced tea can contain 100 to 200 calories depending on the sugar content. Indian chai is calorie-rich, especially when made with full-fat milk and sugar, while East Asian green teas are typically consumed plain, with almost zero calories.

Calories in Bubble Tea and Flavoured Teas

Bubble tea, or boba, is one of the highest-calorie "tea-based" beverages. A single cup with tapioca pearls, milk, and syrup can contain 300 to 500 calories, largely from added sugars and the starchy tapioca balls. Even flavoured teas like peach or lemon iced teas can sneak in 80 to 150 calories per bottle due to sweeteners and additives. These aren’t remotely in the same category as standard tea in terms of nutritional impact.

How Sweeteners Affect Calories in Tea

Non-caloric sweeteners like stevia, erythritol, monk fruit, and sucralose don’t add calories but can still impact your perception of sweetness and potentially stimulate cravings for sugar. While they are a good option for cutting calorie intake, they may not help with overall sugar reduction if they increase your taste threshold for sweetness. However, for most people trying to reduce calories without sacrificing flavour, these are practical substitutes.

Green Tea vs Black Tea for Calories

Both green and black tea contain roughly the same minimal calories when brewed plain. The nutritional difference comes down to antioxidants green tea is richer in catechins, while black tea contains more theaflavins. These compounds don't impact the calorie content but do influence potential health benefits. Either option works as a zero-calorie drink when no milk or sugar is added.

Impact of Serving Size

A “cup” is often interpreted differently. A typical mug may hold 300–350ml, not the 240ml (8 oz) used in nutritional databases. That means if you're adding milk and sugar, the calorie load scales with the volume. A bigger mug with more milk and two sugars can easily reach 70–80 calories without you realizing, especially if you’re topping up frequently throughout the day.

Tea Lattes: Hidden Calorie Bombs

Tea lattes, like a chai latte or matcha latte from a café, often contain 200 to 350 calories per serving, mainly from milk, sweeteners, and flavour syrups. A matcha latte made with whole milk and sweetened powder can have as many calories as a slice of cake. If you’re ordering tea out and trying to watch calories, always ask how it's prepared and consider requesting it unsweetened or with low-fat milk.

Summary

A plain cup of tea contains almost no calories, making it one of the best beverages for hydration and health. Once you add milk and sugar, however, the calorie count can climb from near-zero to over 50 per cup. While that may not seem like much, multiple cups per day can lead to a surprising amount of extra energy intake. Tea can absolutely fit into a healthy diet, especially when enjoyed plain or with low-calorie additions. As with many foods and drinks, the key is in the details and the add-ons