Oolong Tea - History, Uses, and Benefits
Tea, derived from the plant Camellia Sinensis, is one of the oldest and most widely consumed beverage on the planet. Oolong tea is produced by drying wilted, bruised, and partially oxidized tea leaves.  These leaves are then sold in bulk or incorporated in to tea blends. Oolong is rich in bioactive polyphenols like gallocatechin (GC), epigallocatechin (EGC), epigallocatechin gallate (EGCG), epicatechin, gallocatechin gallate, and epicatechin gallate. 
Related: The Importance of Green Tea Extract for Overall Health
Unlike green tea some of the catechins form into theaflavins and thearubigins.  Oolong tea contains more polyphenols than black and roasted tea but less than green tea.  Manufacturers commonly isolate the bioactive components of oolong tea for inclusion in fat burning and general wellness supplements.
In addition to these bioactive compounds oolong tea also contains the alkaloids caffeine, theobromine, and theophylline, amino acids, carbohydrates, chlorophyll, fluoride, aluminum, and trace minerals.  The amino acid, carbohydrate, and mineral content is very low but can certainly add up if you consume oolong tea regularly for a long period of time. The polyphenol, caffeine, vitamin, and mineral content for a cup of oolong tea varies depending on the age of the leaves, quantity of tea leaves used, duration the leaves are steeped, and water temperature.
Oolong Tea UsesEastern cultures have been consuming oolong tea to promote health and longevity for centuries. Oolong tea is most commonly prepared by steeping the hot tea leaves in nearly boiling water. Some people drink the tea to stay hydrated or because they simply enjoy the flavor of this low-calorie non-alcoholic beverage.
A large percentage of oolong tea drinkers consume it for medicinal purposes. Those looking to obtain the benefits of oolong tea without the additional liquid or taste may consume a pill or capsule with the isolated and extracted EGCG, caffeine, and polyphenols.
A growing body of evidence supports oolong tea?s ability to promote fat loss, suppress hunger, increase energy, improve mental alertness and cognition, lower blood glucose levels, slow mineral loss in bones, as well as lower triglyceride and cholesterol levels.
Oolong tea is not a replacement for a prescription medication from your health care professional, nor does it contain all of the vitamins and minerals for proper bodily function. However, the combination of caffeine, polyphenols, antioxidants, and minerals makes oolong tea an attractive beverage for improving and maintaining overall health.
Oolong Tea BenefitsThe most studied benefit of oolong tea in both humans and animals is its ability to increase energy expenditure (EE) and subsequent fat loss. Oolong tea also has positive effects on bone mineral density and key blood markers such as triglycerides and cholesterol.
Scientists asked 12 healthy mean to consume either water, tea from 15 grams of oolong leaves, tea from 7.5 grams of oolong leaves, or water with 270mg of caffeine anhydrous daily for three days. The results of a 24-energy expenditure measurement found that tea brewed with 7.5 grams or 15 grams of oolong leaves increased EE by 2.9% (281 kJ) and 3.4% (331 kJ), respectively, compared to both the water and water with caffeine groups. 
This translates to between 67 and 79 additional calories burned per day. Furthermore, those consuming oolong tea exhibited a 12% higher rate of fat oxidation compared to the water-only group.  Oolong tea can assist with weight loss through its ability to increase total energy expenditure and rate of fat oxidation.
A second small experiment examined the energy expenditure of eleven health Japanese females two hours after consuming either water, oolong tea, or green tea. Those consuming green tea and oolong tea had a 4% and 10% greater increase in energy expenditure compared to the water-only group, respectively. 
Based on these findings one would assuming oolong tea to be the ideal ingredient in fat burning supplements compared to green tea. Interestingly oolong tea has only half the caffeine and EGCG content of green tea but 200% more polymerized polyphenols.  It seems that oolong tea?s polymerized polyphenol content is the primary ingredient for increasing energy expenditure.
A larger study of 102 diet-induced overweight or obese individuals consumed eight grams of oolong tea leaves daily for six weeks and had their body fat measured using a formula with body weight, height, and waist measurements as inputs. 70% of severely obese, 64% of obese, and 66% of overweight individuals lost more than one kilogram (2.2 pounds) of body weight without dietary changes. 
Oolong tea consumption led to an additional one-third pound decrease in bodyweight without subjects have to take any additional action. 12 subjects also experienced significant reductions in subcutaneous fat which lies around the stomach and directly under the skin. 
High levels of subcutaneous fat can lead to a number of health complications and disease states. Oolong tea also significantly lowered triglyceride and cholesterol blood levels in those with elevated values. 
A smaller study of twenty-two subjects found that one month of regular oolong tea intake significantly decreases LDL (bad) cholesterol and adiponectin levels.  Adiponectin plays a role in the breakdown of fatty acids and glucose metabolism. Oolong tea may be an ideal all-natural beverage for those with high triglyceride and cholesterol levels looking to improve overall health.
Oolong tea may also be a beneficial beverage for those with high blood sugar or diabetes. 1,000 milliliters of oolong tea significantly decrease hemoglobin A1c levels.  Hemoglobin A1c provide a snapshot of blood glucose levels over a two to three-month period. A lowered hemoglobin A1c value indicates effective blood glucose management.
A study of twenty Type II diabetics consuming prescription medications for diabetes consumed either 1,5000 milliliters of oolong tea or water daily for thirty days. Those consuming water experienced no changes whereas the oolong tea group experienced decreases of 29% and 21% in blood glucose and fructosamine levels, respectively. 
Fructosamine provides insight on the blood glucose levels over the last two to three weeks.  Oolong tea is not a replacement for prescription medications but it can further assist in the management of blood sugar levels.
An analysis of 680 postmenopausal Chinese women, 124 of which regularly consumed oolong tea and 556 of which did not, found that those consuming oolong tea had nearly 5% higher trochanteric bone and Ward?s triangular bone densities.  Both of these bone areas are found in the hip region and are commonly measured to observe changes in bone mineral density. While regular oolong tea may not prevent osteoporosis or reverse the loss of minerals in bones, it may slow this deterioration and decrease the overall risk of bone fractures.
Oolong tea is an extremely safe beverage for virtually everyone on the planet. The ingredients most likely to cause unwanted side effects include EGCG and caffeine. A study examining a 1200mg daily intake of EGCG in supplement form for one to four weeks found the most common side effects to be minor ? gas, nausea, heartburn, stomach ache, abdominal pain, dizziness, headache, and muscle pain. 
These side effects stopped almost immediately after stopping supplementation. As a reference point, one gram of oolong tea leaves contains just 9mg of EGCG.  it's unlikely you?re going to consume 133 grams or 4.75 ounces of tea day. Oolong tea may not be ideal for those who are extremely sensitive to caffeine.
Although it contains just 3.25mg per gram of tea leaves, translating to 29 to 53mg of caffeine per eight fluid ounce serving, excess caffeine consumption can cause insomnia, restlessness, anxiety, headache, abdominal pain, and nausea.  If you have no problem consuming one to two cups of coffee per day or a pre-workout supplement then you should tolerate moderate oolong tea consumption without any issue.
The best method for increasing your oolong tea consumption is steeping the dried, raw leaves in hot water. Oolong tea extracts are rarely sold as a standalone product or as part of a fat loss supplement. Green or black tea extracts are commonly included in supplements designed to suppress hunger and increase fat loss. However, Man Sports Scorch is the exception as it contains 250mg of P2? Oolong Tea SE, standardized to 30% polymerized polyphenols and 10% EGCG, per 3 capsule serving.
What are your experiences with oolong tea? Let me know in the comments below.
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