Can you drink green tea and do intermittent fasting at the same time? Most people already know drinking green tea has a lot of health benefits and is considered one of the best weight loss drinks.
However, there are some questions about whether it breaks your intermittent fasting. There’s nothing worse than fasting for hours on end only to have broken the fast because you put something in your body that you shouldn’t have.
And to be honest, the answer is complicated to whether or not drinking green tea while intermittent fasting. It can be confusing to find the right answer when it comes to drinking green tea while fasting: is it okay, or will it defeat the purpose?
Here you will find how to drink green tea to maximize its benefits while intermittent fasting, so you can burn more fat and lose more weight while fighting the aging process.
Benefits of Intermittent Fasting and Green Tea
Combining green tea and intermittent fasting is powerful because of the three compounds that work together with your body’s fasted state. Once you understand these three compounds, you’ll quickly see why combining green tea and intermittent fasting can create such great results.
This trio of compounds working together in the fasted state is what can take your results up to the next level. EGCG increases your body’s fat burning, L-theanine keeps you calm and focused, and caffeine suppresses appetite and elevates energy.
EGCG
Green tea is revered in Asian traditions as the “elixir of life” and has been shown in multiple studies to aid in weight loss.1,2 Green tea contains powerful catechins such as epigallocatechin gallate (EGCG), which give it most of its benefits.
This potent antioxidant is what’s responsible for green tea creating such a powerful fat-burning effect and elevating metabolism. Research has shown that it reduces inflammation, enhances heart health, stimulates autophagy, and may even prolong lifespan.3,4,5,6
Research studies have continually found that green tea increases weight loss, and EGCG is the primary driver behind it since it’s a thermogenic.7 This means it actively increases your metabolism, causing your body to burn more calories and fat than it normally would.
Some studies have also suggested green tea can specifically burn more visceral belly fat (deep abdominal fat linked to metabolic disease). According to this study, individuals who drank green tea experienced reductions in their waist size.8
Intermittent fasting also many health benefits and is more than just another fad diet trend. Studies have found that intermittent fasting helps with weight loss, lowers the risk of heart disease, reverses diabetes, and fights off dangerous cancer cells.9,10,11,12,13
EGCG also supports autophagy, which is your body’s cellular cleanup recycling process that helps to get rid of old damaged cells. Autophagy occurs during intermittent fasting, so drinking green tea can help enhance the detoxification process.14
Caffeine
Green tea contains caffeine (one cup = 20-45 mg), but in lower amounts than coffee and black tea. However, caffeine plays a significant role in your intermittent fasting results.
Caffeine is well known as an energy stimulant, but it also increases fat burning and suppresses appetite. It’ll increase thermogenesis, fat oxidation, fat lipolysis, and metabolic rate.15,16
Curbing hunger during your fasting period makes it way easier and more manageable. It’s believed the caffeine in green tea helps to regulate the hunger hormone, ghrelin, making your final hours of fasting more tolerable.
The amount of caffeine can vary depending on the type of green tea, the amount used, water temperature, and brewing time. Sencha and Gyokuro green teas have more caffeine, while Bancha and Genmaicha have less.
L-Theanine
What sets green tea apart from other caffeinated beverages and teas is its high L-theanine content. L-theanine is an amino acid that provides users with a clean, caffeinated energy boost without the jitters or crash.
This compound is what many practicing intermittent fasting choose green tea over coffee. The L-theanine gives a more stable and sustained energy boost as well as a gentle, slow ramp-up lift when combined with the caffeine and green tea.17
This is an ideal combination as the caffeine gives you energy, but L-theanine prevents the jitters to create balanced energy. This is very helpful during long fasting periods to keep focus and productivity to enhance your work performance with better mental clarity.
But Does Green Tea Break a Fast?
Key Takeaways:
Unsweetened green tea does not break a fast. A cup of brewed green tea will contain only a tiny negligible amount of calories, at most 2-3 calories. This is universally agreed upon in the fasting community that unsweetened brewed green tea will not break your fast.
This minimal amount of calories is probably not enough to trigger a metabolic response in the body that would break the fast. Most people following intermittent fasting agree that you can drink green tea, black tea, and black coffee during your fasting windows without concern that it will break your fast.
There’s a guideline called the “50-calorie rule” during intermittent fasting if your main goal is weight loss. This suggests that anything under 50 calories is unlikely to break your fast. This is particularly true with ketosis, which is a fat-burning process where your body burns stored fat for fuel.
The thing with intermittent fasting is that it isn’t like an on/off light switch. Just because you put a very small amount of calories in your body from green tea, it doesn’t mean it’s going to totally break your fast and negate all the benefits.
Green tea is a practically zero-calorie, appetite-suppressing beverage that also contains catechins, which increase fat loss and metabolism. So even by chance, if drinking green tea can blunt some of the fasting effects… then you’ll still come out ahead in the long run due to green tea’s fat-burning impact.
An insulin response in your body due to sugars or carbohydrates can alter your body’s hormonal reactions, which will cause you to break your fast. So, I wouldn’t add any sugar to your green tea, otherwise it will spike your insulin and thus break your fast.
Clean vs Dirty Fasting with Green Tea
Key Takeaways:
I try to minimize any calories or additives during my fasting window personally. The only time I use an additive in my coffee or tea during my fasting window is to increase results by elevating metabolism, improving focus and energy, curbing hunger, and boosting fat burning.
Most intermittent fasting users universally agree that you can drink water, plain black coffee, and unflavored tea (like green tea) during your fasting window.
However, many “clean”, pure fasters are concerned that any substance other than this that enters their body could trigger a metabolic or cephalic phase insulin response, which could interfere with their fasting benefits, such as autophagy and hormonal regulation.
So from this purist, clean, fasting perspective, even adding a little lemon to your green tea could negate your fasting results. They believe anything that causes a sweet taste alone can induce the cephalic response, which can elevate blood sugar and make you hungrier, potentially sabotaging your fast.
But on the other end of the spectrum, dirty fasting users use a more flexible, long-term, results-oriented approach. Their main goal is to focus on adherence and weight loss. So they’re able to add zero or very low calorie additives if it helps increase their results and make the fasting window more sustainable.
If your goal is weight loss through calorie restriction and achieving ketosis, then adding non-nutritive sweeteners and even flavored teas with no calories is acceptable. The cephalic response is a very small response (if at all).18 And fasting users wearing continuous glucose monitors have found that adding additives like stevia don’t cause a significant blood sugar spike that could break fast.
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Green Tea Side Effects During Fasting
“Tea sickness” is a real thing that can happen during intermittent fasting while drinking green tea. And this isn’t just a mild discomfort, but a potentially big problem that could derail your fast.
Tea sickness is the nausea, stomach pain, and sometimes even vomiting that can happen to some people when drinking green tea on an empty stomach. If you’ve ever felt a little queasy after drinking green tea in the morning during your fast, then you’re not the only one.
Some of these symptoms from tea sickness during fasting include:
- Intense nausea
- Stomach pain and cramping
- “Sour stomach” feeling
This mainly happens due to the tannins and catechins, naturally found compounds in green tea. They can irritate your stomach lining, especially when there is no other food in there to buffer their impact. These catechins are what give tea its slightly bitter astringent taste.
Green tea can also stimulate your stomach to produce more acid. This, in turn, on an empty stomach can cause nausea and heartburn.
The caffeine in green tea can contribute to the problem, but it’s interesting that black coffee usually doesn’t cause this effect, even though it has more caffeine. It’s likely due to the high levels of tannins that cause this storm of nausea.
Tea sickness isn’t something new, but has been well known in traditional Chinese tea culture. This is why traditionally you’ll eat small snacks while drinking tea and avoid drinking it on a completely empty stomach.
Here are three ways to prevent this tea sickness by brewing your green tea smarter:
- Lower Water Temperature: Avoid using water that is fully boiling to brew green tea. This can cause the burning of the delicate green tea leaves, resulting in a bitter, astringent green tea beverage that destroys antioxidants, making it more likely to cause nausea(15,16). Use fresh, filtered, and cool water when brewing green tea, with a water temperature between 160-180°F.
- Less Steeping Time: Oversteeping your green tea is a primary cause of excessive tannin release. Steep for only 1-3 minutes, as these shorter steeps yield a milder, less bitter, and less caffeinated green tea brew. This is long enough to extract enough caffeine, flavor, and beneficial compounds while also minimizing the release of harsher tannins.
- Cold Brewing: You can also try cold brewing your green tea, which has become increasingly popular among those who experience an upset stomach when drinking it. Steep green tea leaves or bags in cold water in the fridge for several hours or overnight. This can create a green tea that is smoother, less bitter, and easier on the stomach. Cold brewing will probably extract fewer tannins and catechins, but also release flavor and caffeine.
Green Tea Intermittent Fasting Recipe
I prefer loose matcha green tea because it contains a significantly higher amount of antioxidants than traditional green teas.19 However, feel free to choose any green tea you prefer while fasting.
Water quality is your first priority. Use only fresh, filtered water, as the quality of the water impacts both the flavor of the tea and your health benefits.
Don’t use boiling water! Ideally, use water between 160°F and 180°F. If you don’t have a thermometer or an electric kettle, then you can bring water to a boil, but let it cool for one to two minutes before pouring.
Use about one teaspoon of green tea leaves per cup and 6 to 8 ounces of water. A rounded teaspoon is just about right for most loose-leaf teas. I avoid using tea bags because of the potential for microplastics to leach into your brewed tea from the hot water.
Steep only for 1-3 minutes. Shorter steeps will create a milder, less bitter, less caffeinated brew, but longer steeps will create a stronger brew that can become bitter and astringent. Try experimenting to find your preferred balance of strength and smoothness.
Cover your cup or pot while steeping to trap in the aroma and beneficial volatile oils. Then remove the leaves after steeping to prevent bitterness. You can enjoy it plain or add a squeeze of lemon since the lemon boosts antioxidant absorption.
Avoid adding sugar or honey, as they can both spike your blood sugar and will definitely break your fast. Some people say that adding a small splash of milk can help ease the discomfort on their stomach if they usually get nauseous while drinking green tea during fasting.
If you need to sweeten your green tea, you can try adding stevia, monk fruit or allulose, as it shouldn’t break your fast. I’m not big on artificial sweeteners such as sucralose and aspartame, but if you have to take it then they also shouldn’t break your fast.
What Can You Add To Green Tea When Fasting?
Milk, Cream, Sugar, and Honey: These are universally agreed they break your fast because of their high-calorie and carbohydrate-rich macronutrient content. You’ll spike your blood sugar and then your insulin, which will break your fast. But for those following the 50 calorie rule can add a dollop of cream if it helps them keep fasting for longer.
Flavored Teas: This is a gray area for fasting purists, they argue that the sweet flavor of ingredients like dried fruit pieces or essential oils could trigger a cephalic insulin response, even though there are no calories. But as long as it contains zero calories and flavor, it should help to satisfy cravings, add variety, and help you keep fasting for longer.
Stevia and Artificial Sweeteners: These are definitely highly debated. Overall, most agree that they are acceptable because they are zero calorie and non-nutritive. However, fasting purists avoid them due to concerns about the negative impact on their gut microbiome, wanting to avoid artificial ingredients, and a possible yet subtle insulin response, as they are significantly sweeter than sugar.
Lemon and Spices: Adding a small squeeze of lemon juice or a dash of cinnamon to your green tea is considered acceptable during your intermittent fasting window. But fasting purists are cautious about it because they see it as unnecessary and can take you away from a true water and plain tea fast.
More Teas to Drink While Intermittent Fasting
Now just because this article is about drinking green tea and intermittent fasting it doesn’t mean you can’t drink other kinds of teas too. These are just a handful of my favorite weight loss teas.
Black green tea is also very good to drink while fasting. It contains a high amount of antioxidants as well as a lot of caffeine.20 If you’re sensitive to caffeine then maybe black tea isn’t a great idea for you. But generally more caffeine is associated with higher thermogenic properties and more weight loss.21
Yerba maté is also one of my favorite teas. People call Yerba maté a blend between coffee and tea. It’ll give you the caffeine from coffee without the jitters, but also a ton of antioxidants. Studies have found Yerba maté can help reduce appetite as well as increase your metabolism.22
Pu-erh tea contains a high amount of antioxidants that are powerful for fighting inflammation, weight loss and reverse aging in your body.23 If you have trouble with sun photoaged skin then drinking Pu-erh tea is a great idea.24 Pu-erh tea has also been found to contain a compound known as GABA, which can lower anxiety.25
Oolong tea is also known as the “Black Dragon” but it can be very powerful for helping you lose more weight while fasting.26 It contains a high amount of powerful catechins, which can lower inflammation and improve weight loss.27
Peppermint tea is great to take while fasting because studies have found it can help reduce feelings of hunger. One of the hardest parts about intermittent fasting is the “hunger pangs” that can come with it at times. But studies have found those who have more peppermint in their diet have less appetite and lose more weight too.28
Rooibos tea is another fantastic tea during intermittent fasting. It contains glutathione, which studies have found to be very powerful for fighting the aging process.29 You can also lower stress levels by drinking rooibos tea.
What can you eat or drink while intermittent fasting?
Along with water, you can also drink unsweetened teas, coffee, zero-calorie sparkling waters, lemon water, and pretty much any other beverage that contains 0 cal. You can also take a greens supplement. Or you can take a fiber supplement like psyllium husk to help fill up your stomach while fasting.
A lot of purist fasting experts out there are against taking branched-chain amino acids while fasting. That’s because amino acids can cause a high insulin response in your body. But there also some experts out there who say you can take branched-chain amino acids if you’re working out as your body will quickly metabolize and utilize those amino acids for the recovery process.
Consider adding C8 MCTs to your coffee or tea in the morning during intermittent fasting. They’re quickly converted into ketones, which is the same energy fuel made from your fat stores. This helps to kickstart fat burning by flipping the “metabolic switch”…
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- Enhances Energy & Focus: Provides quick, clean energy & promotes mental clarity
- Manages Appetite: Helps control cravings & supports healthy weight management
Summary
- You can definitely drink unsweetened green tea during your fasting window without fear of it breaking your fast. It will help increase metabolism, burn more fat, curb appetite, and give you an energy boost.
- Just make sure you steep and brew your green tea the right way. Otherwise, you can end up nauseous or upset stomach while fasting.
- Avoid additives in your green tea that can effectively break the fast, but you can add other nutrients that can make it more palatable and even boost your results.
- Sustainability is key, so if drinking green tea helps you keep fasting for longer and makes it more manageable to make it through your fast, then go for it.
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