Does green tea really help with weight loss? (What do research findings say?)

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For thousands of years, green tea has been used as an excellent medicinal beverage to regulate digestion and boost energy. Today, many people drink it primarily to lose weight and burn fat. But if you ask, "Will I lose weight if I drink green tea every day?", we need to understand the actual science behind it.

How does green tea work? Green tea is packed with natural plant compounds and antioxidants that can stimulate our body's metabolism and help break down fat cells. However, most scientific studies related to weight loss were not conducted using the regular green tea beverage that we normally drink. Instead, most researches have been conducted using highly potent green tea extracts or supplements.

Drinking just a regular cup of green tea alone will not lead to sudden weight loss. Combined with a proper diet and exercise, you can certainly incorporate green tea into your daily routine as an excellent healthy beverage to naturally boost your metabolism.

In this article, we will examine in detail the medical evidence and facts regarding how green tea helps with weight loss.

Green tea may help reduce belly fat.

When it comes to weight loss, we cannot expect to lose kilograms of weight immediately after drinking green tea. Studies show that its contribution to weight loss is modest. But one of the biggest hidden health benefits of green tea is that it helps reduce visceral fat in our body.

What Is Visceral Fat, and Why Is It Harmful?

More than the visible belly fat, the fat that accumulates around our internal organs, such as the liver and intestines, is known as 'visceral fat.' This is not easily visible from the outside, but it is highly dangerous. It is when this internal fat increases in the body that the following diseases occur.

• Type 2 Diabetes
• Heart Diseases
• Other severe chronic diseases related to obesity

What do medical studies say about green tea?

According to several medical studies conducted on humans and animals, the catechins and green tea extracts found in green tea play a key role in burning this dangerous visceral fat. If you want to live healthily rather than just lose weight, preventing this internal fat is the most important thing. There is no doubt that green tea will be an excellent natural shield against it.

Read more: Do bananas improve your sex life? What does modern science say?

Does green tea help control our appetite and reduce calorie intake?

The fundamental rule of weight loss is reducing the amount of calories we consume (Calorie Deficit). Many people believe that drinking green tea controls appetite, helping us naturally consume fewer calories. But scientific studies on the role of green tea in controlling appetite show somewhat conflicting results.

The 2023 study

Two hormones, leptin and ghrelin, play a key role in controlling our body's hunger and satiety. According to a comprehensive review published in 2023, consuming green tea extracts was found to have no significant effect on the levels of these two hormones. That is to say, it does not directly suppress your appetite. However, the same study revealed an interesting fact: Even though green tea extract does not control appetite, it has helped reduce body fat percentage, BMI, and malondialdehyde, which indicates oxidative stress in the body.

The 2022 study

Another small study conducted in 2022 with 21 individuals found that drinking green tea before breakfast helps increase the body's energy expenditure (calorie burning). But the important thing to note here is they mentioned that those individuals who drank green tea experienced increased hunger.

Green tea stimulates your body's calorie burning but does not directly help keep your stomach full or reduce the amount of food you eat.

Read more: Fat Burning Heart Rate: What It Really Means, How to Find Yours, and Whether It Actually Helps You Lose Weight

Does green tea help burn calories even at rest? (Resting Metabolic Rate)

Even when we are sleeping or sitting quietly, our body continues to work and burn calories. Scientifically, this is called the Resting Metabolic Rate (RMR). To lose weight easily, this RMR rate needs to be higher. Let's see what science says about whether green tea helps increase this.

What does the 2021 study review say?

According to a comprehensive medical study review published in 2021, some research has found that green tea extracts can help boost our body's RMR rate. That means it can lead your body to burn slightly more calories than usual, even when you are resting without doing any hard work.

However, the experts who compiled this study point out an important thing: Not all studies yielded this positive result. Some studies have also found that green tea caused no change in the RMR rate.

 Even though green tea stimulates our body's total energy expenditure to some extent, it cannot be said for certain yet whether it works the same way for everyone's body type. More research is still needed to come to a complete conclusion regarding this.

Read more: The Science of Bananas: Evidence-Based Benefits for Heart, Gut, and Metabolic Health

Can Green Tea Boost Fat Burning During Exercise?

If you look at the labels of most weight loss and fat-burning supplements sold in the market today, you can see that green tea is included as a key ingredient. However, when it comes to the question of whether green tea actually increases fat burning during exercise, the answers from the scientific world remain mixed. Let's look at what recent studies say about this:

1. Matcha Green Tea and Exercise

In a small study conducted in 2018, it was found that drinking matcha green tea before exercising helps stimulate fat oxidation during the workout. In other words, it acts as a catalyst for breaking down and burning fat faster during exercise.

2. Recent 2024 Study Review

According to a new study review published in 2024, taking green tea supplements along with regular exercise helps to some extent with steady weight management.

However, the researchers also clarified that this green tea consumption did not cause any significant change in lipid markers, such as cholesterol or triglyceride levels in the body.

3. EGCG and Exercise (2017 Study)

EGCG is the most important antioxidant found in green tea. According to a comprehensive study conducted in 2017, some research suggested that when this EGCG compound is taken in combination with exercise, it increases the body's energy expenditure and fat burning. But at the same time, other studies proved that this did not cause any major change.

In short, more detailed research is still needed to fully understand how green tea burns fat in our body, whether during exercise or at rest.

Read more: 5 Medicinal Properties of Papaya: A Scientific Perspective

How does green tea burn fat in our body? (Scientific Explanation)

In our body, fat is stored in cells in the form of 'triglycerides'.If we want to burn this body fat, those fat cells must first be broken down, turning into 'fatty acids' and 'glycerol' to enter our bloodstream. This physiological process is called 'Fat Lipolysis'.

When we exercise, hormones like epinephrine and glucagon are secreted in our body. These are what release fatty acids into the blood, helping to convert and burn them as energy. The medical world calls this process 'Fat Oxidation'.

So, what is the role of green tea in this entire process? Let's see how it helps:

1. Enhancing the potency of hormones

According to some important research, the catechins in green tea—especially the powerful antioxidant called EGCG—stimulate the activity of fat-burning hormones (Catecholamines) in our body, helping to accelerate both the 'lipolysis' and 'oxidation' fat-burning processes.

2. Fat-breaking 'Norepinephrine'

There is a hormone called 'Norepinephrine' in our body. This is an important messenger that orders the cells to break down fat. However, a specific enzyme in our body keeps breaking down this hormone.

This is where green tea may help. The EGCG in green tea blocks the activity of that enzyme. As a result, the level of the hormone norepinephrine increases in the body, and fat cells begin to break down much faster.

3. The Role of Caffeine

The caffeine naturally present in green tea helps stimulate the body's fat metabolism. Specifically, studies show that even when you are at rest and not exercising, this caffeine helps promote fat burning to some extent.

Ultimately, green tea stimulates your fat cells to break down more fat. That broken-down fat then enters the bloodstream and is completely burned by muscle cells to be used as energy.

Key Components of Green Tea That May Help Burn Fat

Green tea leaves are rich in various natural plant compounds that benefit our body. These help fight against inflammation and oxidative stress in the body, while also helping to control cholesterol and insulin levels. Thereby, they serve as an excellent defense in preventing chronic diseases such as diabetes and obesity.

Importantly, green tea contains two primary components that can help with weight loss:

1. Catechins
2. Caffeine

These increase the number of calories our body burns daily (energy expenditure) and promote weight loss by stimulating fat oxidation, metabolism, and the body's heat production (thermogenesis).

1. What are catechins? (Catechins & EGCG)

Catechins are a type of natural compounds found in plants known as 'polyphenols' (flavonoids). The most important among the catechins in green tea is epigallocatechin gallate (EGCG). EGCG accounts for up to 80% of the total catechins present in green tea.

Some medical research indicates that this EGCG greatly helps in reducing the following key indicators related to obesity:

• Total body weight
• Body fat percentage
• Waist-to-hip ratio
• Waist circumference
• BMI

2. The power of caffeine (Caffeine)

Caffeine is a globally well-known stimulant. It has been found that this activates our body's nervous system and also promotes the fat-burning process.

Although both EGCG and caffeine in green tea can individually help with weight loss, there is one thing we must clearly understand. Not all medical studies fully support these weight loss effects. There is also a possibility that this may not cause any significant changes for certain body types.

Read more: Medicinal Benefits of Mango: A Scientific Overview

FAQs

01. Which type of green tea is best for weight loss?

With many varieties like Matcha, Sencha, and Jasmine green tea available in the market, it is natural for many people to have the question, "Which type of green tea should I drink to lose weight faster?"

However, there is limited medical research available to date that compares the weight-loss effects between different types of green tea.

What current science tells us is:

• Regular Green Tea: Regularly drinking the standard green tea you consume daily, along with a proper diet, can somewhat help maintain a healthy weight.

• Green Tea Extracts: Studies show that taking high-potency green tea supplements or extracts may provide slightly better benefits in fat burning compared to the regular beverage.

Instead of falling for the fancy advertisements in the market, making quality, unadulterated regular green tea a part of your daily health routine is the best and safest way.

02. Can you lose weight with green tea in 2 weeks?

If you ask, "I have an important occasion coming up in the next 2 weeks, can I lose weight by drinking green tea before that?", the answer that science gives is: "Definitely not." The change in your body weight just by drinking green tea in mere two weeks will be very, very negligible.

What do science and research say? Most medical studies conducted on green tea and weight loss have been based on a time frame of at least 6 weeks or longer.

Even after consistent observation over those many weeks, not all studies yielded favorable results. Only a few people noticed small changes in their body weight.

Weight loss is not a miracle that happens in just 2 weeks. It is a long-term journey. Instead of believing advertisements that claim you can lose weight in 2 weeks, you can achieve good results only if you turn drinking green tea into a long-term habit, combined with a healthy diet and exercise.

03. How much green tea should you drink a day to lose weight?

"Right, if green tea helps with weight loss, how many cups should I drink a day?" is the next question for many people. A major medical study published in 2020 provides a clear answer to this.

The measurement provided by the 2020 study

According to a comprehensive medical research review published in 2020, it has been found that the following approach should be followed to healthily reduce body weight and BMI:

• Amount: A minimum of 500 milligrams (mg) of green tea extract daily.
• Duration: This must be consumed continuously for 12 weeks (about 3 months).

How much should you drink if it is regular green tea? 500 milligrams of extract is equivalent to 2 to 3 cups of good quality green tea that we normally prepare at home. Therefore, drinking 2 - 3 cups a day would be the right amount.

Drinking green tea alone while eating unhealthy food will not lead to weight loss. Researchers firmly state that this 500-milligram amount will healthily boost your weight loss only when green tea is paired as a supplement with a proper balanced diet and regular exercise.

Bottom Line

There is no denying that green tea is an excellent health drink that has been used for many years for its incredible medicinal properties, such as reducing inflammation (anti-inflammatory), preventing oxidation (antioxidative), and fighting cancer (anticancer).

When it comes to body weight, some research shows that certain natural compounds in green tea can stimulate the body's metabolism and fat oxidation, helping with weight loss to some extent. However, there are an equal number of medical studies that contradict this, showing that it causes no significant change.

Therefore, instead of viewing green tea as a 'magic drink' for weight loss, it is correct to see it as a 'daily habit' that improves overall health.

If you want to lose body weight in a healthy manner, it is best to consult and get advice from a qualified medical professional or a dietitian. Only they can guide you correctly to design the right diet and exercise plan suited for your body type.

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