Oolong Tea – Benefits for weight loss and potential side effects
Is Oolong tea the Chinese secret for weight loss? The benefits of oolong tea for weight loss have been studied for some time.
This tea also called ‘Wu long tea‘ for those who are trying to lose weight should become an everyday drink. Why and how Oolong tea may help you to shed pounds we will try to show you in this article.
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What is Oolong Tea?
Oolong tea is slightly fermented and semi-oxidized tea made from the leaves, buds, and stems of the Camellia sinensis plant. The same plant used to make black and green tea, the difference is in how this tea is processed.
Unlike black tea which is fully oxidized with deep black leaves (oxidation is what turns green leaves into a deep black color), oolong tea is partly oxidized. Green tea is not allowed to oxidize much, green tea leaves are steamed, roasted, or pan-fired during processing which prevents them from oxidizing.
Oolong tea is somewhere between black and green tea and it is partly oxidized. This partial oxidation is the core of oolong’s tea color and taste. The degree of oxidation can vary from 8 to 85% depending on the variety and production process.
Think of oolong tea as a type between unoxidized green tea and fully oxidized black tea. The lower the number the closer the flavor will be to green tea and the same is true for the color.
What does oolong tea taste like?
The taste of Oolong tea depends on the levels of oxidation of the tea, and different styles of oolong tea can vary in flavor. They can be woody and thick with roasted aromas, sweet and fruity with honey aromas, or green and fresh with complex aromas. All depending on horticulture and style of production.
Oolong tea comes in two shapes such as ball-shaped or with long twisted leaves. There are many varieties of oolong tea, but the most famous oolong comes from China and Taiwan.
Taiwanese high mountain oolong teas are ball-shaped including a bud and more leaves with whole branches. Chinese oolong teas have twisted long and elegant leaves, but should never include whole branches.
Nutrition facts for Oolong Tea
Like black and green teas oolong tea contains vitamins, minerals, and antioxidants.
A cup of brewed tea will contain:
- Potassium: 1% of the RDI
- Manganese: 26% of the RDI
- Fluoride: 5-24 of the RDI
- Sodium: 1% of the RDI
- Magnesium: 1% of the RDI
- Niacin: 1% of the RDI
- Caffeine: 36 mg
One of the major classes of polyphenols that are connected to weight loss is a group of compounds called catechins. We will show you how these polyphenols present in oolong tea may help you with weight loss further in this article.
Besides caffeine, which is also found in black, white, and green tea, oolong tea also contains theanine, an amino acid responsible for the tea’s relaxing effect.
Oolong Tea benefits for weight loss
The benefits of oolong tea for weight loss have been confirmed in many studies, and that’s why this tea became one of the most popular teas when it comes to losing weight.
Increase energy expenditure (EE) and inhibit the absorption of fat and carbohydrates are two main ways to reduce food-related body weight.
Improving lipid metabolism
In a Chinese study published in 2009 where a total of 8 grams of oolong tea a day for 6 weeks was ingested by 102 diet-induced overweight or obese subjects was found that a total of 70% of the severely obese subjects did show a decrease of more than 1 kg in body weight, including 22% who lost more than 3 kg.
The conclusion from this study is that oolong tea could decrease body fat content and reduce body weight by improving lipid metabolism. Also, the chronic consumption of oolong tea may prevent obesity.
The caffeine content in oolong tea: An 8 ounce serving of oolong tea contains 37-38 milligrams of caffeine, which is about 1/4 of the amount of caffeine in the same amount of coffee.
Effect of tea polyphenols and caffeine mix on fat burning
Some of the polyphenols in oolong tea may boost metabolism and decrease the amount of fat absorbed from your diet. These polyphenols are also thought to activate enzymes that help you use stored fat for energy.
According to Chinese belief oolong tea is effective in the control of body weight. Few controlled studies have been conducted to measure the impact of tea on energy expenditure on humans.
The study included 12 male volunteers who were given 4 separate beverage formulas over 3 consecutive days. These beverage formulas consisted of 1) full-strength tea, 2) caffeinated water with caffeine equal to full strength tea, 3) half strength tea and 4) non-caffeinated water.
After measuring the EE in participants results showed:
- 3% higher EE levels when they drank full-strength tea or caffeinated water versus the non caffeinated water.
- They burned on average 67 or more calories when drinking full-strength tea
- Increased fat burning (fat oxidation) by 12% after consuming full-strength tea versus the caffeinated water
These results show that a component other than caffeine is responsible for promoting fat as an energy source. As a conclusion from this study comes that drinking oolong tea can tell your body to burn fat for energy.
This indicates that the fat-burning effects of oolong tea are caused by plant compounds in tea, not just caffeine.
Good to remember: The combination of polyphenols and caffeine in oolong tea can help increase the number of calories and fat burned each day.
The polyphenols in oolong tea specifically act on the enzymes pancreatic lipase, glucosidase, and amylase.
According to a report from 2018 when these enzymes are shut off your body can’t absorb fats and sugars so effectively so the number of calories that are absorbed decreases and you don’t gain weight as quickly or easily.
Shutting down the activity of certain enzymes that are involved in digestion is another way that oolong tea may contribute to weight loss.
In the same study was made a comparison between green tea and oolong tea polyphenols. The study noted that polyphenols in oolong tea allow your body to produce more SCAFs than the polyphenols in green tea.
SCAFs (short-chain fatty acids) – Bacteria that naturally live in our digestive tract when exposed to certain compounds produce SCAFAs as a byproduct. When SCAFAs reach the liver, they can increase the amount of fat and calories you burn and slow down the conversion of glucose into fat.
Effect on gut bacteria
Oolong tea may help you to lose weight but also the polyphenols in oolong tea positively affect the bacteria in your gut and that helps not just with weight loss but also benefit your health in a number of other ways.
The polyphenols of the tea almost 90% pass through the digestive system unabsorbed. They go right to the gut bacteria feeding them and helping to boost the good bacteria.
When your digestive system is balanced or when the good bacteria outnumber the bad it helps to balance the hormones (ghrelin and leptin) that signal hunger and satiety. This improves the way your body responds to insulin and glucose and that has a positive effect on the amount of body fat you store.
If we simplify this, your body burns fat instead of storing it, your blood sugar stays balanced, and you feel hungry only when truly hungry.
Further reading: 5 Best Herbal Teas for Weight Loss: Delicious and Healthy
Possible side effects and concerns
Oolong tea is generally considered to be safe if you drink it in moderation. Responsible drinking of any tea will not cause any side effects.
However, as we mentioned above it does contain caffeine and when consumed in excess, caffeine may lead to a number of adverse effects such as insomnia, anxiety, increased blood pressure and heart rate, headaches.
A gram of dry oolong tea leaf contains about 10-40 mg of caffeine, with an average of 20-30 mg per gram. Drinking around 15 grams of the dry leaf should be safe.
Western brewing methods use 2-3 grams of tea, while the eastern method uses 5-7 grams. However, to be fully extracted caffeine require high water temperature and long steeping.
Learn more: Does Tea or Coffee Have More Caffeine?
According to the USDA and EFSA daily intake of 400 mg of caffeine is considered to be safe. This is equivalent to 48-80 oz (1.4 – 2.4 liters) per day. If we take that the average cup is 8 oz you can safely drink 6-10 cups of oolong tea without consuming too much caffeine.
If you are sensitive to caffeine avoid drinking too much oolong tea and pregnant women are advised to not consume more than 200 mg of caffeine, which is equal to 3-5 cups of oolong tea per day.
Additionally, the flavonoids in tea can bind the iron found in plant foods, reducing absorption from the digestive system by 15-67%. So for people with low iron levels, it’s recommended to avoid drinking tea with meals and to consume vitamin-C-rich foods to help increase iron absorption.
How to make oolong tea for weight loss
Making oolong tea that may help you to lose weight is so easy, it’s like making every tea. You can use oolong tea bags or oolong tea leaves to make this delicious beverage. Also, you can combine it with green tea to increase the overall impact.
Here are a few methods of preparing it for weight loss:
Method 1: Making oolong tea with tea leaves with an infuser
- Heat water 190-200 degrees Fahrenheit on the stove.
- Pour the water into a cup.
- Fill a tea infuser with a teaspoon of loose oolong tea leaves.
- Place in a cup and allow it to steep for 2-6 minutes.
Method 2: Making oolong tea with green tea
- Bring a cup of water to a boil and remove from the flame immediately
- Add oolong and green tea
- Let it steep for about 3-4 minutes
- Strain before drinking
Method 3: Making oolong tea and cinnamon
- Soak the cinnamon stick in a cup of water overnight
- In the morning boil the water with the cinnamon
- Wait until the water level drops to its half
- Remove from the heat and add the oolong tea leaves
- Let it steep for 3 minutes
- Remove the tea leaves and cinnamon stick before drinking
Frequently asked questions and answers
You can consume oolong tea in the morning with breakfast, 30 minutes before lunch or dinner, or with your evening snack.
It is recommended to drink 2-3 cups a day. Don’t overdo it in hope of losing weight quickly. If you drink too much the presence of caffeine may cause some side effects like insomnia, increased heart rate, anxiety, etc.
The polyphenols in both oolong and green tea boost metabolism, but recent studies show that oolong tea is twice more effective when it comes to weight loss. Oolong tea has more caffeine than green tea, and caffeine tends to increase a person’s energy expenditure.
Yes, you can drink oolong tea every day if you are not sensitive to caffeine, and drinking less than 1 liter per day is considered to be safe for most adults.
The antioxidants in oolong tea might help treat acne and blemishes, wrinkles, and other signs of aging. Drinking oolong tea thrice a day can give you good results, also you can simply steep the tea bags in water and use it to cleanse your face first thing in the morning.
Final words about oolong tea and weight loss correlation
From all evidence mentioned above, we can conclude that drinking oolong tea can provide positive effects when it comes to weight loss. You must keep in mind that just drinking tea can’t help you to shed pounds, it can be just another extra thing that you should add to a healthy diet and lifestyle.
If you want to lose weight you must eat right, exercise, and tea can be just an addition to these. And oolong tea is a great choice to add to your weight loss diet.
It is so delicious and you can drink it hot or cold, enjoy a cup of oolong before a workout or walk, drink in the afternoon to stave off late day sweet cravings and energy slumps.
If you haven’t tasted it yet, give it a try you will love it!