Exploring the Different Types of Tea

by Amylee Amos PhD, RDN, IFMCPNutrition
Assorted teas in jars

I spent the better part of the last week in Las Vegas at the World Tea Expo. I sipped on a lot of teas, observed many of the rituals and ceremonial aspects of tea service, and talked with the world tea experts about why tea has been a part of our history since ancient times. In many parts of the world, tea is deeply ingrained in culture: the traditional tea ceremonies in Japan, high tea service in the UK, and the passing of the shared calabash gourd of Mate in South America. All different types of teas and all different settings; how unique that virtually the same beverage can have so many meanings and places within cultures.

As much as I’ve always enjoyed tea and consumed it regularly, I never realized the complexity of the tea industry until the World Tea Expo. The tea industry, like so many other industries, is saturated. There are hundreds of thousands of tea products on the market. Are they all created equally? Are they all safe for consumption? Do they all have the same benefit to our health? These are important questions to ask.

There are so many factors at play in the growing, processing, production, and sale of tea. For example, where tea is grown can greatly influence not just taste, but health impact. Tea grown in polluted areas not only negates the beneficial health aspects of tea, it can contribute to disease. Additionally, much tea is grown in third world countries, making the trading practices impossible to ignore. Does the tea we drink exploit indigenous people or does it support them? And then there is the question of the product itself. Are compounds added to the tea we’re drinking? Artificial flavors, but even natural flavor additives are something to consider when choosing a tea product. Needless to say, you need to know what you’re consuming and you need to make sure that you’re only consuming the absolute highest quality product.

All tea (black, white, green, oolong) is made from the same plant species, Camelia sinensis, with different strains native to different parts of the world. It is an evergreen species and naturally contains caffeine. What makes the different types of teas unique in terms of appearance, taste, and nutritional content is the processing of the leaves once they have been picked, specifically the oxidation or fermentation process. Drinking tea of any kind provides tremendous health benefit, including protective effects in skin, lung, prostate, and breast cancers, as well as cardiovascular benefits, neurologic benefits, and metabolic improvements, just to skim the surface (1,2). Below are the main categories of tea and what you need to know when deciding what to drink.

Black Tea

Black tea is the most popular tea of the Western world. Black teas are traditionally from China, India, and Sri Lanka, but also Nepal, Turkey, and Kenya. Black teas are allowed to wither after being picked, and are fully oxidized or fermented, which is why they have a black color.

Because black tea is fully oxidized, some of the polyphenols, the phytonutrients found in tea, are broken down, so overall it has a lower phytonutrient composition than does white or green tea. However, black tea is rich in phytonutrients called thearubigins, which also serve as antioxidants providing their own benefits (3).

Oolong Tea

Oolong tea is a cross between black tea and green tea. Oolong tea is semi-oxidized, giving it the complexity and depth of a black tea, but the brightness and earthiness of a green tea. Because oolong tea is a cross between green and black, it is especially palatable, a great choice for the tea novice. Oolong teas are most popular in China, but are gaining popularity in Western cultures. In terms of health benefit, it is has somewhere between the benefits of a black tea and a green tea.

Green Tea

Green tea is unoxidized, which is why it retains its natural green color. After the leaves are picked, they are rapidly steamed or pan-fried, which deactivates the enzymes which would otherwise contribute to the oxidation process. When it comes to the health benefits of tea, green tea certainly gets the most attention, and for good reason. Some of the primary health benefits attributed to green tea include cardiovascular benefit, anti inflammatory effects, cancer prevention, anti-arthritic properties, neuroprotective properties, and cholesterol lowering effects, among others (4).

Green tea is rich in catechins, most notably EGCG. These catechins are found in far greater quantity in green tea than in black or oolong tea.  EGCG provides most of the cancer preventative effects of green tea (5). It does this through programmed cell death in cancer cells, blocking cell proliferation signaling in cancer cells, among other mechanisms.

Beyond the impact of EGCG, l-theanine is an amino acid found in green tea with well studied health benefits. L-theanine has been demonstrated to reduce psychologic and physiologic stress, which is why green tea is well known to be a calming and comforting beverage (6). Even more exciting, l-theanine has been shown to attenuate beta amyloid induced memory impairment in mice (7). This presents a strong case for the regular intake of green tea to prevent and treat Alzheimer’s disease.

White Tea

White tea, often called Silver Needles, is the least processed of all teas. White tea is made from just the young bud of the tea plant, and excludes the mature tea leaves. Because of this, white tea is much more expensive, since far less product is yielded from the same process. White tea is completely unoxidized and contains the least amount of caffeine compared to other teas. It is very light and delicate in taste and aroma, even when steeped for an extended period of time. Like green tea, white tea is rich in catechins, providing the same antioxidant benefits.

Pu’erh Tea

Pu’erh is tea that has been fermented and aged, then packed into cakes or bricks. Like a fine wine, it’s believed that pu’erh tea gets better as it ages if it has been stored correctly. In China, fine pu’erh tea can sell at an extremely high price point. It has a mellow, almost sweet taste. The Chinese consider pu’erh to be the ultimate health beverage, and attribute benefits such as cholesterol lowering, hangover curing, and cognitive enhancing, among others. Much of the research on pu'erh tea has been done in rats, so the validity of these claims in humans is still unknown (8,9). However, the research on pu'erh is quite exciting, and will hopefully inspire more research in humans.

Herbal Tea

Herbal tea is not actually tea at all, as it does not contain the Camelia sinensis plant. This is why herbal tea is naturally caffeine free. Herbal tea consists of herbs, spices, and other plants that are boiled or steeped in hot water. The practice of using herbal tea for medicinal purposes far outdates the use of actual tea. Common herbal teas include peppermint, chamomile, lemongrass, rooibos, and hibiscus. Other health promoting herbals include turmeric, ginger, valerian, jasmine, lavender, and rose. The health benefits of herbals are innumerous. We could write (and we should write) entire blogs dedicated to each of these herbs and spices because the health benefits are unique to each compound and truly remarkable.

What’s the Takeaway?

Make sure you’re drinking pure tea, with no added flavors or preservatives. If you feel like you need more flavor, add your own with things like fresh lemon, ginger, or turmeric. Opt for organic tea whenever possible, so you know you’re getting a pesticide free, non-GMO product. But also make sure you opt for Fairtrade. Fairtrade products do just that, they make trade more fair for the farmers and workers who are growing and harvesting the product. Buying fair trade tea means that the people who are growing and picking the tea you’re drinking are doing so in decent working conditions and at a decent wage. Fairtrade prohibits forced labor and child labor. Use your purchase of tea to get a product that is good for your health, but that’s also good for other people. Also, make sure that you look for Rainforest Alliance Certified tea. A product that bears the Rainforest Alliance seal means that the tea farm and manufacturing process has been audited and meet standards for environmental sustainability.

At the World Tea Expo, I met so many business owners and entrepreneurs who have created fabulous products in terms of taste and health, but at the same time are supporting and providing for the people who are on the other side of the consumer chain. Buy from companies that are providing fair, living wages to their workers, who are offering them healthcare or supporting their basic needs. You can even support companies who are going above and beyond by offering scholarships for education for workers and their children. If you need suggestions for some of the best small tea companies out there, let us know! The vote we make with our wallet is as important as the vote we make at the polls (arguably more important, but that’s a conversation for another day). Now go pour yourself a cuppa!


  1. Khan, N., & Mukhtar, H. (2013). Tea and Health: Studies in Humans. Current Pharmaceutical Design, 19(34), 6141–6147.
  2. Yang, C.S., & Landau, J.M. (2000). Effects of Tea Consumption on Nutrition and Health. Journal of Nutrition, 130(10): 2409-2412.
  3. Leung, L.K., Su, Y., Chen, R., Zhang, Z., Huang, Y., & Chen, Z. (2001). Theaflavins in Black Tea and Catechins in Green Tea Are Equally Effective Antioxidants, The Journal of Nutrition, 131(9): 2248–225.
  4. Chacko, S. M., Thambi, P. T., Kuttan, R., & Nishigaki, I. (2010). Beneficial effects of green tea: A literature review. Chinese Medicine, 5, 13.
  5. Mukhtar, H. & Ahmad, N. (2000). Tea polyphenols: prevention of cancer and optimizing health. American Journal of Clinical Nutrition, 71(suppl): 1698-1702.
  6. Kimura, K., Ozeki, M., Juneja, L.R., & Ohira, H. (2007). L-theanine reduces psychological and physiological stress responses. Biological Psychology, 74(1): 39-45.
  7. Kim, T.I., Lee, Y.K., Park, S.G., Choi, I.S., Ban, J.O., Park, H.K., Nam, S.Y., Yun, Y.W., Han, S.B., Oh, K.W., & Hong, J.T. (2009). L-theanine, an amino acid in green tea, attenuates beta amyloid induced cognitive dysfunction and neurotoxicity: reduction in oxidative damage and inactivation of ERK/p38 kinase and NfKb pathways. Free Radical Biology and Medicine, 47(11): 1601-1610.
  8. Yang, J., Zhou, W., Gu, Y., Dai, J., Li, X., Tai, P., … Zhang, Y. (2018). Protective effect of Pu-erh tea extracts against ethanol-induced gastric mucosal damage in rats. Biomedical Reports, 8(4), 335–342.
  9. Cao, Z.G., Gu, D.H., Lin, Q.Y., Xu, Z.Q., Huang, Q.C., Rao, H., Liu, E.W., Jia, J.J., & Ge, C.R. (2011). Effect of pu-erh tea on body fat and lipid profiles in rats with diet-induced obesity. Phytother Res., 25(2): 234-238.