By Dr. Mercola
While there is growing interest in green tea, particularly the famous matcha green tea from Japan, there are other varieties that can offer exemplary benefits as well. Take oolong, for example: It offers potential for weight loss, heart health and a wide array of health issues,1 and yet it only accounts for 2 percent of overall tea consumption worldwide.2
This article puts the spotlight on oolong tea: its origins, how it’s produced and potential effects it can have on your health. Brew yourself a delicious cup of this tea and take delight in every sip.
What Is Oolong Tea?
While there are various teas enjoyed all over the world, there are actually only four main types of tea: black, white, green and oolong. These are the varieties produced from the Camellia sinensis plant. Herbal teas are actually not considered “true” teas, as they do not come from Camellia sinensis.4
What sets these four apart is their degree of fermentation. Oolong, made from the buds and stems of the plant, falls somewhere in between green tea and black tea. Organic oolong tea is described as “slightly fermented and semi-oxidized,”5 and as a result has a taste that falls between these two types of tea.
The flavor depends on the oxidation level of oolong, which can vary from 8 to 80 percent. Less oxidized oolongs may have a fresh green tea flavor, while more oxidized varieties may have a malty black tea flavor.6
Oolong tea is said to have originated from China and Taiwan. There are many different types of oolong tea, with the most famous type hailing from the Fuijan province in China.7 There are several interesting accounts on how this tea came to be discovered. One story said that a man from the Anxi region of Fuijan became distracted during the harvest and accidentally left his tea leaves to oxidize. There are different versions of the man’s name – Wulong, Sulong or Wuliang – which became the basis of the tea’s name, “oolong.”8
You can brew oolong by steeping loose tea leaves or you can simply buy oolong tea bags. Just make sure to avoid tea bags made with plastic, such as nylon, thermoplastic, PVC or polypropylene, which can leach unwanted and potentially harmful chemicals into your beverage.
Health Benefits of Oolong Tea
Because it falls between black tea and green tea, oolong tea offers both of these teas’ benefits, making it one of the healthiest tea varieties you can consume.
Oolong tea is rich in antioxidants called polyphenols, which include theaflavins, thearubigins and Epigallocatechin gallate (EGCG). These beneficial compounds account for oolong tea’s positive effects. Another beneficial component in it is theanine, an amino acid with relaxing properties. The caffeine in oolong tea is also responsible for some of its benefits.9
• Helps with weight management: The polyphenols in oolong tea help control fat metabolism in the body by activating certain enzymes. A 2001 study published in the Journal of Nutrition found that participants who ingested either full-strength or diluted oolong tea burned 2.9 to 3.4 percent more total calories daily.12
• Assists in free radical elimination: The antioxidant properties of polyphenols help remove excessive free radicals in the body, which play a role in various diseases, such as stroke, cancer, diabetes and rheumatoid arthritis.
• May boost brain function: One study found that people who regularly drank black and oolong tea had 64 percent lower risk of brain function decline.
This may be because of various factors, such as the caffeine, which can increase the release of the brain messenger hormones norepinephrine and dopamine, therefore improving mood, attention and brain function. The theanine in oolong is believed to help boost attention and relieve anxiety as well.
• Helps keep your bones strong: Drinking black, green or oolong tea every day (in a 10-year period) is said to increase bone mineral density by 2 percent, according to one study.13 Having a higher bone mineral density may help reduce the risk of fractures.
• Maintains good heart health: This is believed to be brought on by the antioxidants in the tea. One study involving over 76,000 Japanese adults found that those who consumed 8 ounces or more of oolong tea daily reduced their heart disease risk by 61 percent.14
In a separate study done in China, a 39 percent reduced stroke risk was seen in adults who drank 16 ounces of green tea or oolong tea daily.15
|Amt. Per |
|% Daily |
|Calories||2.4 kcal||0 %|
|Total Fat||0 g||0 %|
|Saturated Fat||0 g||0 %|
|Trans Fat||0 g|
|Cholesterol||0 mg||0 %|
|Sodium||7.1 mg||0 %|
|Total Carbohydrate||0.4 g||0 %|
|Dietary Fiber||0 g||0 %|
|Protein||0 g||0 %|
|Vitamin A0 %||Vitamin C||0 %|
|Calcium0 %||Iron||0 %|
* Percent Daily Values are based on a 2,000 calorie diet. Your daily values may be higher or lower depending on your calorie needs.
How to Make Oolong Tea
Oolong can come in different leaf shapes and may have varying oxidations levels. For this reason, there is no one-size-fits-all technique for steeping this tea. The Kitchn provides general guidelines on how to brew oolong tea:16
- If the oolong is rolled in into balls, use 1 teaspoon of tea leaves per 6 ounces of water. If what you have are large open leaves, use two tablespoons for the same amount of water.
- Use fresh cold water that has not been boiled before. Do not used distilled water, as it will give your oolong a flat flavor.
- Boil your water to 180 to 200 degrees Fahrenheit before steeping the tea.
- How long you should steep oolong depends on how weak or strong you want the tea to be. Ideally, steeping time should be anywhere from one to five minutes.
Oolong leaves needs room to “unfold” and release their flavor, so you should use a basket-style infuser instead of a ball-style infuser. Another good idea is to directly brew the tea leaves in the pot or cup and then just strain them out.
Many people love using oolong to make milk tea, with various recipes available today. However, I advise doing this sparingly, as adding milk may significantly reduce its health benefits. This is because the proteins in the milk may bind to and neutralize the antioxidants in tea.17
How to Store Oolong Tea
Because oolong is semi-fermented, its shelf life is somewhat longer than green tea, with heavily oxidized oolong varieties lasting as long as two years. However, this still largely depends on the degree of fermentation and how well it is stored. Loose leaf oolong tea sold in bulk also tends to become stale quicker.
The trick to prolonging the shelf life of oolong is making sure that it’s stored properly. Put it in an airtight container and keep in a dry, dark cabinet.18 Refrain from placing it under direct sunlight or heat, and put it away from pantry items like spices and coffee that can leach their flavors and odors onto the tea.19 In addition, lightly oxidized oolongs may store better in the refrigerator to slow down oxidation.20
A Note Regarding the Caffeine in Oolong Tea
Oolong does have caffeine, but its levels actually fall somewhere in between black tea and green tea. The caffeine levels in oolong are also lower than coffee. For example, an 8-ounce cup only contains one-fourth the caffeine in the same amount of coffee.21
Keep in mind that there are numerous factors that may influence the caffeine content in oolong, such as the processing method and how the tea was brewed. You may get lower caffeine levels if you drink lightly oxidized oolong tea, but be exposed to more caffeine if you drink a highly oxidized oolong product.22
If you are truly concerned about the caffeine in oolong tea, you can try these measures to minimize the caffeine in your brew:23
- Use a smaller amount of tea leaves
- Do not drink the first brew
- Only brew oolong leaves for a short period of time
It’s also a good idea to ask the vendor or manufacturer about the caffeine levels in the product you’re buying.
Oolong Tea May Have Side Effects for Caffeine-Sensitive People
Even if the caffeine content of oolong is significantly lower than that of coffee, those who are sensitive to this stimulant should still limit their intake. Excessive consumption may lead to caffeine overload, causing potential side effects such as:24
Increased urine flow
In addition, tea, in general, may decrease the amount of iron you get from plant foods. Hence, if you want to drink oolong tea, you should make sure to get enough vitamin C, which can increase the amount of iron from plant foods.25
Don’t Miss Out on the Outstanding Benefits of Oolong Tea
Oolong may not be as widely talked about as green tea, but maybe it should be. The health benefits mentioned above should be enough to convince you to try this tea.
Just make sure to get oolong from a reliable manufacturer and drink it in moderation, especially if you’re sensitive to caffeine. Brew yourself a cup of oolong today and start enjoying the many wholesome benefits of this beverage!
Frequently Asked Questions (FAQs) About Oolong Tea
Q: Is oolong tea a type of black tea?
A: No. While they both come from the same Camellia sinensis plant, oolong tea is not black tea. Black tea is fully oxidized, while oolong is semi-oxidized. It falls between green tea and black tea.
Q: What does oolong tea taste like?
A: Depending on the oxidation of oolong, its flavor may vary. Less oxidized oolong may have a fresh green tea flavor, while heavily oxidized varieties may have a malty taste reminiscent of black tea.
Q: Where can you buy oolong tea?
A: You can buy oolong tea in any health store, and some specialty tea online stores carry this tea variety as well. The most famous oolongs come from Taiwan and China, although other countries like Japan, India, Sri Lanka and Thailand are also making their own versions of oolong tea.26
Q: Is oolong tea caffeinated?
A: Yes, oolong tea contains caffeine, albeit in smaller amounts than black tea and coffee.
Q: How much caffeine in oolong tea?
A: This depends on the brand or variety. Caffeine Informer tested four oolong types and found their caffeine levels to range from just 16.6 to 55.4 milligrams per cup.27 In general, oolong has more caffeine than green tea, but less than black tea.
Q: Is oolong tea fermented?
A: The correct term is “semi-fermented.” Oolong is partially oxidized, and is somewhere in the middle of green tea and black tea.
Q: Is oolong tea acidic?
A: No. Oolong tea is said to be less acidic than green tea, making it a welcome drink for people with stomach problems.28
Note: When buying tea of any kind, make sure that it’s organic and grown in a pristine environment. The Camellia sinensis plant in particular is very efficient in absorbing lead, fluoride and other heavy metals and pesticides from the soil, which can then be taken up into the leaves. To avoid ingesting these dangerous toxins, a clean growing environment is essential, so that you can be sure you’re ingesting only pure, high-quality tea.