Can You Drink Black Tea While Fasting? Know Before You Do!

Around the world, many people from different cultures do fasting, and I am one of them. As black tea lovers, the biggest problem we have to face is whether we can drink black tea while fasting or not. I used to drink black tea while fasting since it does not have any calories. However, I wanted you to know the scientific approach of that, which was the reason for writing this article.

Unsweetened black tea is allowed while fasting because it is a beverage not containing any calories. As long as you do not add any sugar, honey, cream, or any other dairy alternative to black tea, it will not cause an insulin spike. Therefore, it is safe to drink and very beneficial while fasting.

Black tea is allowed to drink while intermittent fasting, but it has many benefits of drinking black tea.  Black tea can be your partner to make your fast easier. Read on, and you will know more!

What is intermittent fasting, and why people doing it?

Intermittent fasting is not a new concept, although its benefits have been explored recently. For example, recent research has found that intermittent fasting helps you lose weight[1]Anton SD, Moehl K, Donahoo WT, Marosi K, Lee SA, Mainous AG, et al. Flipping the Metabolic Switch: Understanding and Applying the Health Benefits of Fasting. It might also help you normalize blood glucose levels which is essential for a diabetic patient.


Intermittent fasting allows our body to switch metabolically[2]de Cabo R, Mattson MP. Effects of Intermittent Fasting on Health, Aging, and Disease. N Engl J Med. This means while you are fasting at least for 12 hours without any calories from carbs, proteins, or fats, insulin will not be produced.

In this period, the body starts to use the energy from ketone bodies made from fats instead of glucose stored in our body. The process is called ketogenesis. Getting energy from ketone bodies will burn your body fat deposits and cause stable blood glucose levels.

Despite numerous health benefits of intermittent fasting, we all find it challenging to keep away from the food we love, even for few hours. Different patterns of intermittent fasting allow you to fast during different time frames.

I have listed some of them below;

  • Time-restricted fasting
  • 5:2 method
  • 24 hours fasting
  • OMAD 

Can black tea break your fast?

So back to black tea. During the fasting period, you are only allowed to drink water and other non-calorie beverages.  These beverages can be tea, coffee, and maybe lime juice added water.

It is recommended to take liquids during fasting because you can feel full after you drink these beverages. It will also keep your stomach active, which is an essential thing while doing fasting.

However, the tea you are drinking mustn’t contain any additives. These include sugar alternatives, sugars, honey creams, dairy anything else that you can think of. But you can add lime juice to black tea because it does not contain any calories.

However, some people complain that they feel hungry after drinking black tea or coffee during fasting. This might be because they use to eat something while they drink black on typical days.

So, after drinking tea, they immediately crave food which was their habit. However, you can control these cravings by being motivated or avoiding drinking tea, and opt for water only.

Why black tea is a good choice while fasting?

It is okay to drink black tea while fasting; it does not harm people. On the contrary, it benefits from drinking black tea while fasting.


In one study done with type 2 diabetes, people found that they could lose weight after fasting for two weeks, and their blood glucose levels improved dramatically[3]Rothenberg DO, Zhou C, Zhang L. A Review on the Weight-Loss Effects of Oxidized Tea PolyphenolsMolecules. 2018; 23(5):1176.[4]Arnason TG, Bowen MW, Mansell KD. Effects of intermittent fasting on health markers in those with type 2 diabetes: A pilot study. World J Diabetes. 2017 Apr 15;8(4):154-164. doi: 10.4239/wjd.v8.i4.154. PMID: 28465792; PMCID: PMC5394735.. If you have heard about the benefits of black tea, black tea has proven to improve blood glucose levels, and also it might help you lose weight.

So, if we combined this intermittent fasting and drinking black tea, it will probably result in better outcomes.

One study done with 1422 people has shown that fasting for 21 days with black tea was beneficial. Participants who drank black tea improved their physical well-being and mental wellbeing. They were also able to overcome some of the health problems. As an example, people who suffer from cardiovascular disease can improve their conditions[5]Wilhelmi de Toledo F, Grundler F, Bergouignan A, Drinda S, Michalsen A. Safety, health improvement and well-being during a 4 to 21-day fasting period in an observational study including 1422 subjectsPLoS One. 2019;14(1):e0209353. Published 2019 Jan 2. doi:10.1371/journal.pone.0209353

The most important aspect of drinking black tea during fasting is reducing hunger. According to one study, the phenolic compounds called catechins in black tea help reduce the production of ghrelin in our bodies. So, we can suggest that it might reduce your hunger by reducing this hunger signaling hormone ghrelin[6]Chen IJ, Liu CY, Chiu JP, Hsu CH. Therapeutic effect of high-dose green tea extract on weight reduction: A randomized, double-blind, placebo-controlled clinical trial. Clin Nutr. 2016 Jun;35(3):592-9. doi: 10.1016/j.clnu.2015.05.003. Epub 2015 May 29. PMID: 26093535.

Also, you might be irritated at the first of starting intermittent fasting. So here is another benefit for you about drinking black tea while fasting. Black tea can help you relax and lower your stress levels. This is done by an amino acid found in black tea, which is L-theanine [7]Hidese S, Ogawa S, Ota M, Ishida I, Yasukawa Z, Ozeki M, Kunugi H. Effects of L-Theanine Administration on Stress-Related Symptoms and Cognitive Functions in Healthy Adults: A Randomized Controlled Trial. Nutrients. 2019 Oct 3;11(10):2362. doi: 10.3390/nu11102362. PMID: 31623400; PMCID: PMC6836118..

How much black tea can you drink while fasting?

It is all safe to drink around 3 to 5 cups of black tea per one day. However, it is safe to avoid black tea if you experience acid reflux, heart burning, or gastric symptoms after drinking black tea. 

Ways to drink black tea while fasting 

Of course, when preparing black tea, it should be free from any sugar, Honey milk, and milk alternatives.  You can prepare plain black tea to drink during fasting by brewing black tea leaves or black tea bags in boiling water.

However, you cannot mix in anything that can add calories, as mentioned before, including sugar, syrups, honey, and any Dairy alternatives. In your eating window, you can prepare black tea and drink in any way you want.

However, make sure you stay on the daily limits of drinking black tea.

How caffeine in black tea affect fasting


You might be wondering that black tea is a caffeine-rich drink and what it might do with fasting. Well, black tea has about 47 mg of caffeine, and you can safely consume up to 400 mg of caffeine per day. So you might think that it is OK to drink 8 cups of black tea per day. 

However, other foods that we consume in a day or so contribute to this caffeine intake of your day. So usually, according to health professionals, it safe to drink around 3 to 4 cups of black tea per day. So even though you are fasting, make sure you stay on limits. 

If you drink an excessive amount of black tea and 5 cups per day, you may experience some side effects. For example, you might experience anxiety, insomnia, digestive issues, muscle breakdown, high blood pressure, rapid heart rate, and fatigue.

But, most importantly, it will make it hard for you to sleep, which is essential while doing intermittent fasting because good sleep makes it easy for you to fast.

Can you trim down excess weight by drinking black tea?

Some studies claim black tea can help you lose weight. A study done with 111 participants has shown that drinking 3 cups of black tea per day for three months can significantly reduce your waist circumference.


This weight loss effect is due to flavones in black tea[8]Bøhn SK, Croft KD, Burrows S, Puddey IB, Mulder TP, Fuchs D, Woodman RJ, Hodgson JM. Effects of black tea on body composition and metabolic outcomes related to cardiovascular disease risk: a randomized controlled trial. Food Funct. 2014 Jul 25;5(7):1613-20. doi: 10.1039/c4fo00209a. PMID: 24889137.. Research done with mice has also found that catechins in black tea can reduce body fat[9]Nagao T, Komine Y, Soga S, Meguro S, Hase T, Tanaka Y, Tokimitsu I. Ingestion of a tea rich in catechins leads to a reduction in body fat and malondialdehyde-modified LDL in men. Am J Clin Nutr. 2005 Jan;81(1):122-9. doi: 10.1093/ajcn/81.1.122. PMID: 15640470.. This gives us hope that that black tea might help you lose weight.

When you combine intermittent fasting that has proven to reduce body weight and black tea that acts as an aid for fasting, you will probably see the results sooner.


In conclusion, Intermittent fasting is a growing method of dieting that has captured the sight of many people and researchers. This is because of the vast number of benefits intermittent fasting claims to have.

It is primarily used for weight loss and controlling the blood glucose levels of people with type 2 diabetes. The hardest part of this method is fasting. Black tea is allowed to take while doing fasting.

Black tea is something that you can take to ease the fasting period and also get more benefits. If you drink black tea while fasting, you will be able to double the benefits of this method due to the synergetic effect of both black tea and intermittent fasting.


Can You drink black tea while fasting for a blood test?

Fasting for blood tests usually requires 12-hour fasting. For these tests, anything other than water is not recommended during fasting hours. This means that you cannot drink black tea while fasting for a blood test because test results might not be accurate.

In addition, coffee and black tea can affect the test results due to compounds in them, such as polyphenols and caffeine. Caffein can also be a diuretic and affect the results of the test.

Can you drink black tea while water fasting?

Water fasting is another method of fasting, and it is not intermittent fasting. In water fasting, everything is restricted except the water, and it is used as a method for weight loss. However, it is not allowed to drink black tea during a water fast because it only allows water during the fasting period.