Oolong tea, an exotic brew from China, might seem intuitively healthy when drunk as it is meant to be – plain and without too many add-ins. The Chinese have also, for generations, believed that oolong tea can help reduce weight and maintain this weight loss. But does current day research agree? As it turns out, this tea might have the potential to do that and more. Here’s data you should consider if you’d like to switch to this kind of tea for your morning or evening pick-me-up!
If you’re wondering what oolong tea is in the first place, here’s a quick introduction to this brew from China. A kind of tea that’s made from the leaves of the Camellia sinensis plant, oolong essentially has the same “parent” plant as green and black tea. Somewhere between green and black teas on the processing front, Oolong teas are partially oxidized. Black teas, on the other hand, are oxidized while green teas are dried quickly without any oxidizing. Some say that oolong, a mildly floral tasting tea, combines the best of both worlds! Moreover, while green tea leaves are rolled, oolong tea leaves are treated carefully so their cell structure remains intact without any rolling, which arguably makes them more nutrient-rich in antioxidants like polyphenols. When it comes to weight loss, the antioxidant polyphenols like flavonoids and tannins in the tea, along with the caffeine and amino acids, may have a synergistic effect, translating to the following benefits.1
1. Increases Energy Expenditure And Metabolic Rate
By burning more calories per day, you improve your chances of weight loss – especially if you cut down on your dietary intake of calories overall. Oolong tea can help strike at the root of the matter and amp up your metabolic rate. As one study found, men who took full strength oolong tea had a significantly higher energy expenditure than those who just had plain water they burned about 281 kJ more every day. The tea, in this case, was brewed from 15 gm of tea leaves in all, drunk in five 300 ml servings through the day. The fat oxidation for this group was also higher than those who drank water by 12%.2
While this study was on men alone, a separate study found similar effects in women too. The study, conducted in Japan, found that energy expenditure at 60 minutes, 90 minutes, and 120 minutes after consuming oolong tea was significantly higher than when plain water was consumed.3
2. Helps Reduce Weight And Burn Fat
If you’re someone who is carrying around extra weight, oolong tea might help with weight loss. As one piece of research found, 70% of severely obese individuals in the study who had 8 gm of oolong tea daily for a period of 6 weeks saw their body weight drop by over 1 kg, while 22% actually saw weight loss in excess of 3 kg! About 66% of those who were overweight and 64% of those who were obese saw weight loss of over 1 kg during this time, and 12% of all test subjects also saw their subcutaneous fat content decrease.4 As seen in the other study above, the oxidation or burning of fat was 12% higher for subjects who drank oolong tea every day.5
Oolong’s anti-obesity effect, seen in tests on obese and overweight people, has also been backed by animal studies. As an animal study found, test animals who were administered oolong tea alongside a high-fat diet did not develop fatty liver. Obesity stemming from the diet was also prevented.6 The researchers attributed this effect to both the caffeine and other polyphenols in oolong that helped modulate the metabolism of fats by the liver and pancreas.
In another study, adding just 5% oolong tea powder to a high-fat diet in test animals helped reduce fat accumulation and body weight both. While overall body weight reduced by about 10% over a 10-week period, adipose tissue (fat) weight dropped by a whopping 51%! A separate study showed similar beneficial effects on body weight gain on test subjects fed a high-sugar diet along with oolong tea extracts. This reduced by 35%. Researchers also found oolong tea intake reduced the fat-to-body weight ratio.7
3. May Reduce Dietary Fat Absorption
Oolong not only helps cut fat that has accumulated in your body but may also modulate the way it is absorbed and processed. In other words, having oolong tea may even reduce how much fat you absorb and retain in your body from a meal. As one piece of research found, when healthy subjects had polyphenol-enriched oolong tea while on a high-fat diet, it helped increase the amount of lipids excreted by the body into feces. On days when the test subjects had the tea, the cholesterol excretion was higher than when they had a placebo. The proportion of lipids in the feces was 21% when the subjects had the polyphenol-enriched oolong tea compared to the 13% when they had the tea-flavored placebo. This, added to the fact that taking the tea seemed to show no side effects, led researchers to suggest that polyphenol-enriched oolong tea could be taken as a daily beverage by healthy individuals to control the absorption of lipids.8
4. Has Hypolipidemic Properties
Polyphenols in oolong tea also have an antioxidant and anti-inflammatory effect. Both oxidative stress and chronic inflammation have been linked to being overweight or obese, one leading to the other and creating a vicious cycle. Having oolong tea may help cut both these factors implicated in obesity and metabolic disorders.
Oolong tea’s favorable impact on lipid metabolism also has benefits if you have high cholesterol or triglyceride levels. Hyperlipidemia is a problem many obese people struggle with and this, in turn, can be a risk factor for cardiovascular problems. Oolong tea may be able to help on this front as well. Animal studies show that when test animals were fed oolong tea leaves, as well as the leaves of other kinds of tea (green, black, and pu-erh), it not only helped reduce body weight but also their total cholesterol, low-density lipoprotein (LDL) cholesterol, and triglyceride levels significantly.9
5. Is A Better Option Than Other Calorie-Laden Drinks
The simplest math when it comes to weight loss is to ensure that the calories you burn exceed the calories you consume every day. Called a calorie deficit, this can help you knock off weight bit by bit every day. If you manage a calorie deficit of say 500 calories a day, you can expect a weight loss of anywhere from 0.5kg to 1kg (1lb to 2lb) in a week.10
Oolong tea has just a couple of calories per cup, in fact almost negligible if it is just the tea leaves and water in the brew.11 If you add in some sugar or milk, you’ll need to factor those calories in as well, but even then, it is likely to be much lower than pre-sweetened drinks or sugary sodas and fruit juices. To give you an understanding of how many calories you stand to save by switching to oolong, here’s a look at the typical calorie content of some popular beverages.
- Cola, 16 fl oz can: 207 calories12
- Hot cocoa, 1 cup: 192 calories13
- Coffee (ready to drink sweetened, with milk), 1 cup: 186 calories14
- Milk, 1 cup: 122 calories15
- Orange juice, 1 cup: 112 calories16
That said, while oolong tea is a better bet than other drinks calorie wise, it does have 16 gm of caffeine per 100 gm of brewed tea.17 This would translate to about 30–50 mg of caffeine per 8 oz cup of tea as per some estimates. If you overdo it, you may see side effects like headaches, tremors, diarrhea, sleep problems, and heartburn. So limit your intake to 2–3 cups a day and remember to factor in other sources of caffeine you’ve had as well.
Club Oolong Tea Intake With Exercise And A Healthy Diet
Remember, weight loss won’t be achieved by drinking tea alone! You’ll need to also modify your lifestyle so you’re eating a healthy balanced diet rich in fiber and plenty of fresh fruit and vegetables as well as whole grains. Incorporating some regular physical exercise is also important – authorities like the World Health Organization suggest a minimum of 150 minutes of moderate exercise every week.18 If you’re trying to lose weight, you may need to increase that level of exercise and try fit in at least an hour a day, combining strength training (like weight training or resistance training or bodyweight exercises) to build muscle, with aerobic exercises like cycling, brisk walks, swimming, or dance. Once you’ve made these alterations to your lifestyle, you can raise that cup of oolong tea and make a toast to your good health!
- 1,3 – Komatsu, Tatsushi, Masayo Nakamori, Keiko Komatsu, Kazuaki Hosoda, Mariko Okamura, Kenji Toyama, Yoshiyuki Ishikura, Tohru Sakai, Daisuke Kunii, and Shigeru Yamamoto. “Oolong tea increases energy metabolism in Japanese females.” Journal of Medical Investigation 50, no. 3/4 (2003): 170-175.
- 2,5 – Rumpler, William, James Seale, Beverly Clevidence, Joseph Judd, Eugene Wiley, Shigeru Yamamoto, Tatsushi Komatsu, Tetsuya Sawaki, Yoshiyuki Ishikura, and Kazuaki Hosoda. “Oolong tea increases metabolic rate and fat oxidation in men.” The Journal of Nutrition 131, no. 11 (2001): 2848-2852.
- 4 – He, Rong-rong, Ling Chen, Bing-hui Lin, Yokichi Matsui, Xin-sheng Yao, and Hiroshi Kurihara. “Beneficial effects of oolong tea consumption on diet-induced overweight and obese subjects.” Chinese journal of integrative medicine 15, no. 1 (2009): 34-41.
- 6 – Han, L. K., T. Takaku, J. Li, Y. Kimura, and H. Okuda. “Anti-obesity action of oolong tea.” International journal of obesity 23, no. 1 (1999): 98.
- 7 – Preedy, Victor R., ed. Tea in health and disease prevention. Academic Press, 2012.
- 8 – Hsu, T. F., A. Kusumoto, K. Abe, K. Hosoda, Y. Kiso, M. F. Wang, and S. Yamamoto. “Polyphenol-enriched oolong tea increases fecal lipid excretion.” European journal of clinical nutrition 60, no. 11 (2006): 1330.
- 9 – Lin, Jen‐Kun, and Shoei‐Yn Lin‐Shiau. “Mechanisms of hypolipidemic and anti‐obesity effects of tea and tea polyphenols.” Molecular nutrition & food research 50, no. 2 (2006): 211-217.
- 10 – Work out how much weight you need to lose. NHS.
- 11,17 – Beverages, tea, Oolong, brewed. United States Department of Agriculture, Agricultural Research Service.
- 12 – Beverages, carbonated, cola, regular. United States Department of Agriculture, Agricultural Research Service.
- 13 – Milk, chocolate beverage, hot cocoa, homemade. United States Department of Agriculture, Agricultural Research Service.
- 14,15 – Beverages, coffee, ready to drink, milk based, sweetened. United States Department of Agriculture, Agricultural Research Service.
- 16 – Orange juice, raw. United States Department of Agriculture, Agricultural Research Service.
- 18 – Physical Activity and Adults. WHO.