We’re often asked by tea drinkers which tea is the healthiest. The question poses quite the conundrum because there isn’t one tea that is right for all health goals. Some teas contain compounds that help to boost relaxation and calm the mind while others contain caffeine that can help boost energy. Some teas have been heavily researched by the scientific community while others are just emerging on the scene.

When it comes to true teas, the question becomes even more complicated since they are derived from the same plant leaves. We’ve put together this brief breakdown of oolong tea vs black tea to help you understand the difference between the two and uncover which one is healthier for your lifestyle.

Tea Basics

Oolong tea and black tea are both types of tea known as true teas — that means they are made from the leaves of the tea plant known as the Camellia sinensis plant. All other teas are actually called herbal tisanes or herbal teas since they don't technically contain leaves of the tea plant. There are only five true teas including white tea, pu-erh tea, green tea, black tea, and oolong tea. If you're a tea drinker, you know that these teas are vastly different from one another even though they are made from the same tea leaves.

The main reason these teas have unique characteristic arises from the way they are produced. Green tea and white tea undergo a minimal production process that creates a delicate flavor profile that is floral and earthy with a light or mild body. White and green tea leaves are harvested and dried immediately using the power of the sun or steaming and firing methods.

Oolong tea is the first true tea that is oxidized — a process where enzymes are exposed to oxygen, resulting in a richer flavor and darker color. Depending on the tea master's preference, oolong teas can be oxidized anywhere from 8 to 80 percent. Lightly oxidized teas are floral and light with mildly sweet flavors while heavily oxidized teas are darker with earthy and robust notes.

Black tea and pu-erh tea are the most oxidized of the true teas. Pu-erh tea undergoes an aging oxidation process, making it unique from these other oxidized teas. Black tea, on the other hand, is oxidized completely using traditional methods. The oxidation process results in rich, earthy flavors and a full body. Black teas have strong flavor notes and are a great replacement for a cup of coffee.

Dive Deeper Into Oolong Tea

Oolong leaf tea is largely a Chinese tea. Most of these types of tea are produced in China, though there are a few other small regions that craft oolong teas mainly in Taiwan. The main oolong cultivation regions in China include the Fujian Province, particularly in the Wuyi Mountains and Anxi County. The oolong leaves here are steeped in a rich history.

These types of tea were popular favorites among elite leaders dating back to the Qing Dynasty. One particular variety of oolong tea — known as Black Dragon tea — was served as a tribute tea. Some of the highest quality oolong teas today include Da Hong Pao, which is one of the world's most expensive teas, and Bai Jiguan tea. Both of these teas are cultivated in the Wuyi Mountains. Wildly popular Anxi region oolongs include Tieguanyin, which is known as Iron Goddess of mercy tea and Huangjin Gui.

The caffeine content of oolong tea leaves varies depending on its oxidation level. More heavily oxidized oolongs tend to have higher caffeine levels compared to lightly oxidized ones. In general, oolong tea contains 35 to 60 milligrams of caffeine.

Get the Scoop on Black Tea

Black tea is a caffeine-rich tea that is commonly used as an alternative to coffee. The tea boast robust flavors with hints of chocolate, caramel, and woodsy flavors. Black tea is largely produced in China – in the Yunnan Province— and in India, though plantations across the globe cultivate this tea.

In Britain, English black teas like English Breakfast tea and Earl Grey tea, which features the addition of bergamot rinds are popular favorites. In India, black tea is cultivated using a strain unique to the region. High quality varieties include Assam and Darjeeling, which are a key component of masala chai.

In China, two popular black teas include Lapsang Souchong, Keemun, and black pearl gunpowder tea. Lapsang Souchong tea leaves are roasted over open pine fires, creating a tea that invokes visions of woodsy campfires. It is rich and features a potent piney fragrance. Gunpowder tea derives its name from the appearance of the tea leaves, which are rolled into tight balls that unfurl when infused in water.

Black tea has the highest amount of caffeine among the true teas — aside from some powdered forms of Sencha or matcha green tea. Black tea can contain up to 130 milligrams of caffeine per 8-ounce serving — that's about half the amount present in a cup of coffee. It also contains an amino acid known as l-theanine that can help boost focus without the jitters.

Which One is Healthier?

Different teas offer different health benefits thanks to their chemical composition. Since oolong and black tea are derived from the same tea plant, they offer many of the same benefits. Tea leaves from the Camellia sinensis plant contain antioxidants known as catechins, theaflavins, tannins, and polyphenols that have been linked to extensive health benefits (1). In fact, research shows that drinking tea may help to decrease risk factors of heart disease including high blood pressure, irregular blood sugar levels – which can lead to type 2 diabetes — and cholesterol levels (2).

Research pitting each type of tea against another is limited. Thus it is difficult to say which true tea is the healthiest. The benefits of oolong tea are very similar to black tea benefits. Green tea is arguably far better researched than other true teas, though that doesn't necessarily mean it is healthier than oolong tea or black tea.

When it comes to the healthiest teas, your health goals will enable you to choose the right one for your needs. If you're looking to boost weight loss, drinking tea with a high caffeine content — like heavily oxidized oolong teas or black tea — may help you reach your goals sooner. Some research shows that a combination of caffeine and tea antioxidants may speed up metabolism by encouraging fat oxidation (3). If you're looking to boost energy levels, black tea may be a better choice than oolong since it has a higher caffeine content.

Tea consumption is also great for overall health. Drinking tea is a great way to stay hydrated and the high concentration of antioxidants can help fight free radicals and stave off infections. We like to say, the best and healthiest tea types are the ones you enjoy and actually drink.

There's no point drinking a tea you hate the flavor of simply because a research study says it's healthy. There are plenty of teas that offer health benefits that are backed up by scientific research and great flavor. Find the flavors you love and drink those teas to enjoy a healthier existence. Consider this your green light to drink oolong tea, black tea, or any herbal flavor that suits your fancy – just stick to loose leaf tea rather than tea bags for the best flavor and benefits.


1. https://academic.oup.com/jn/article/133/10/3285S/4687618

2. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3123419/

3. https://academic.oup.com/jn/article/131/11/2848/4686734