Fasting is a strict way of life, generally done for religious reasons. However, it may be done for medical reasons or as intermittent fasting for some hours as a habit. 

The point of interval fasting is that you consume all your calories quickly – for example, between 12 and 6 p.m. – and then don’t eat anything for the rest of the day. And the health benefits of fasting range from reducing weight and blood pressure to increasing insulin sensitivity.

Table Of Contents

Coffee During Intermittent Fasting

Coffee is a popular beverage enjoyed by various people daily. It’s often consumed to boost energy and can be found in cafes, restaurants, and even at home.

So, can you have coffee when fasting? Whether you’re fasting or not, we know coffee is a good thing to drink while you’re awake. For example, it may help you stay alert during the day or boost your energy levels after lunchtime. But what about when you fast? Can we consume coffee while fasting? This post will provide an answer to that.

Types of Intermittent Fasting

If you decide to practice this eating regimen, there are several types of intermittent fasting:

  • The 5:2 Diet: Five days a week, you usually eat without any restrictions, and on two days of the week, you limit your calorie intake to 500 or 600 calories per day. This diet recommends 500 calories for women and 600 calories for men.
  • Fasting 16/8: Following this method, you limit your food intake to an 8-hour interval each day and spend the remaining 16 hours fasting.
  • Alternate Day Fast: This method requires fasting every other day. The first day you usually eat, and the next day you either completely starve for 24 hours or eat less than 500 calories. This pattern lasts for a week and can be more intense than recommended for beginners.
  • One meal a day: In this type of intermittent fasting, you eat only one meal daily, usually dinner. No calories are consumed the rest of the time.

Coffee While Water Fasting: What You Need to Know About the Effects 

Water fasting is a practice that requires one to consume water solely for a specific duration, which can range from 24 hours to multiple days or even weeks. It’s often undertaken for weight loss, detoxification, or spiritual reasons. However, many people who practice water fasting often need clarification on whether they can still consume coffee during the fast. So, read why!

  • Stimulant Properties

Coffee retains caffeine, a central nervous system push. It’s often used to enhance alertness and cognitive performance. During a water fast, it could counteract some lethargy or brain fog accompanying caloric restriction. However, it’s essential to remember that individual responses to caffeine can vary significantly.

  • Autophagy

Autophagy is a physiological process in which your body cleanses damaged cells to regenerate newer, healthier ones. Water fasting is known to trigger autophagy. There is evidence that coffee consumption can also stimulate autophagy in the liver, heart, and muscle tissue. Thus, coffee may complement the effects of water fasting on cellular regeneration and repair.

  • Appetite Suppression

Coffee suppresses appetite, which might be beneficial during a water fast. This could help you get through the fasting period without discomfort from hunger pangs.

  • Diuretic Effects

Coffee contains a diuretic mark, which means it can increase urine production. This effect might cause you to lose more water and essential electrolytes during a water fast, potentially leading to dehydration or electrolyte imbalances.

Potential Drawbacks

Despite some potential benefits, there are several potential drawbacks to consider when consuming coffee while water fasting:

  • Disrupted Sleep

Drinking coffee, which contains caffeine, can disrupt your sleep cycle. If you’re already dealing with potential energy level fluctuations due to fasting, insufficient sleep could exacerbate feelings of fatigue.

  • Increased Heart Rate

Caffeine can raise your heart rate. While this mightn’t be an issue for everyone, it could be problematic for individuals with certain heart conditions.

  • Gastric Irritation

Coffee can annoy the stomach lining and may lead to digestive discomfort in some individuals, especially when consumed without food.

Does coffee break a fast

Does Coffee Break a Fast or Intermittent Fasting?

The critical factor in intermittent fasting is the number of calories. As long as the food or drink contains no calories, you will not break your fast. This means that black coffee goes great with intermittent fasting. Technically, a cup of coffee contains about 4 calories because of the coffee beans’ natural oils and amino acids – but four calories aren’t enough to affect your hunger state.

A fast is a period of abstinence from all food and drink, typically for religious or health reasons. The word fast in this context can also be used metaphorically to mean abstaining from partaking in something (such as an activity or food).

Any food or drink that is not pure water breaks the fast. Coffee, tea, and other beverages are not considered pure water.

Coffee is a diuretic and can make you urinate more frequently. This can increase the number of times you go to the bathroom, leading to dehydration.

Coffee also contains a stimulant known as caffeine. Caffeine can increase your heart rate and also raise blood pressure. If you have high blood pressure or diabetes, avoiding coffee when fasting may be best because it could worsen your condition.

Does Black Coffee Break a Fast?

During a fast, black coffee calorie are so low, drink it is a beautiful beverage to keep on hand. It is high in antioxidants, which boost energy and maintain healthy skin. It also includes several vitamins and minerals.

Caffeine in black coffee also aids in metabolism and the breakdown of fat cells for energy. This implies you fast for extended periods without having to eat. 

The Effect of Coffee on Intermittent Fasting

Drinking coffee can increase the benefits of interval fasting, helping you see health improvements faster.

  • How Coffee Intensifies Ketosis?

Fasting is a quick and easy way to get into ketosis. When you don’t eat food, your body “eats” carbohydrate stores and then begins to burn fat as fuel. Thus, fasting goes well with the keto diet, helping your body get into ketosis faster.

And drinking coffee while fasting can make the keto diet more effective. Recent studies have shown that caffeine increases ketone production.

Can You Drink Coffee While Fasting?

The short answer is yes.

The long answer is that it depends on what coffee you are drinking, how much caffeine it has, and whether it contains other ingredients that may affect your fast.

Coffee beans contain a lot of caffeine, which can negatively impact your fast if taken too frequently or in large quantities (more than 1 cup per day). In general, most people should consume no more than 200 mg (or 8 oz) of caffeinated beverages per day during a fast state; however, if you need extra energy without affecting your diet plan or mood, then, by all means, add a cup of coffee to your morning routine.

Can You Drink Coffee With Milk While Intermittent Fasting?

Whether you can drink coffee with milk while intermittent fasting is a common question, and the answer might be more complex than you think.

Coffee in its black form is a zero- or near-zero-calorie beverage without added sugar or milk. It’s generally accepted as part of the fasting period in intermittent fasting regimens. The caffeine in coffee helps control your appetite during your fasting window [1].

But what happens when you add milk to your coffee?

Whether dairy or plant-based, milk contains calories, primarily from its carbohydrate and fat content. Depending on how much milk you add, a cup of coffee with milk can range from 20 to 100 calories. That may not seem like a lot, but consuming any amount of calories will break a fast.

Consuming calories, even in small amounts, initiates metabolic processes that interfere with fasting. These include stimulating insulin secretion, an essential hormone in storing nutrients from food [2]. Therefore, from a strict perspective, adding milk to your coffee would break your fast.

However, some people follow a more flexible approach to intermittent fasting. 

They may allow for a small number of calories during the fasting window, typically around 50. This is periodically directed to as “modified fasting.” 

In this case, a small splash of milk in your coffee likely won’t significantly impact your fasting state or the benefits you derive from intermittent fasting. Still, it’s essential to be mindful not to overdo it and keep the portion of milk small.

Ultimately, deciding whether to add milk to your coffee during your fasting window will depend on your goals and how your body responds. If your primary aim with intermittent fasting is weight loss and having a bit of milk in your coffee helps you stick to your fasting-eating schedule, it might be worth the slight deviation.

Bulletproof Coffee While Fasting: Can You Drink It and Still Reap the Benefits 

Bulletproof coffee, a beverage consisting of coffee, grass-fed butter, and medium-chain triglyceride (MCT) oil, has become popular among fasting and low-carb communities. Many people wonder whether they can consume this beverage while fasting and still obtain the benefits of fasting. Let’s delve into this.

The concept behind bulletproof coffee is that it’s high in fat but low in carbohydrates. This food item can help maintain consistent energy levels, improve mind clearness, and nurture a sense of satiety, making it a good option for fasting.

However, when it comes to fasting, one fundamental principle is the absence of caloric intake for a certain period. This abstention allows the body to take a break from digesting food, switch to burning stored fat for energy, and engage in various metabolic processes, including cellular repair and insulin regulation.

In the strictest sense, consuming bulletproof coffee, which is high in calories due to the butter and MCT oil, would technically break a fast because it engages your digestive system to process the fat. It might not stimulate insulin-like carbohydrates, but the high caloric content can interfere with the metabolic state of fasting.

However, drinking bulletproof coffee, especially during intermittent fasting, mightn’t drastically interfere with the potential benefits. The fat content could help suppress appetite, maintaining a feeling of fullness, benefiting those struggling with hunger pangs during fasting.

Furthermore, bulletproof coffee can fit within a ketogenic diet framework, often paired with intermittent fasting, where the body is shifted into a fat-burning mode called ketosis. Bulletproof coffee’s high fat, low carbohydrate content could support this metabolic state.

NOTE: while this might work for some, it’s only for some. Individual metabolic responses vary greatly, and for some, consuming bulletproof coffee could lead to feelings of lethargy or gastrointestinal discomfort.

Whether bulletproof coffee is suitable during fasting is complex and depends mainly on your specific goals, dietary habits, and how your body responds. 

Why Does Coffee Not Breakfast?

A cup of coffee has less than 5 calories and no fat. Therefore, you can take it while fasting. 

Coffee has numerous health benefits, such as reducing the risk of certain cancers, improving brain function, and preventing heart disease.

However, caffeine can be toxic if you consume too much in one sitting. The kidneys work hard to eliminate this toxin, which can lead to dehydration and headaches in some people.

Does Coffee Boost Metabolism

Studies have shown that caffeine does increase metabolism slightly. But, in contrast, some studies have found that drinking coffee while fasting lowers your metabolic rate and makes it harder to lose weight! Why? Because caffeine can suppress the amount of fat-burning hormones like leptin, ghrelin, cortisol, and insulin — all of which are essential for losing weight.

However, coffee and sugar also contain a substance called chlorogenic acid, which can help reduce the amount of fat stored in the body. Chlorogenic acid also can increase muscle glucose uptake, which helps enhance performance during physical activities. So there is no right or wrong answer to the question, ‘Does coffee boost metabolism.’ It all depends on the factors at play. 

What Can I Drink During Intermittent Fasting to Keep You Hydrated and Satisfied?

Here are ten super drinks you can enjoy during intermittent fasting to keep you hydrated and satisfied. 

1. Water

Let’s start with the most straightforward and essential drink—water! It’s calorie-free, refreshing, and necessary for maintaining proper hydration during intermittent fasting. Consuming at least 8 cups (64 ounces) of water daily is recommended to maintain adequate hydration.

2. Herbal Tea

During fasting periods, herbal teas like chamomile, peppermint, or ginger tea are a great choice. They are naturally caffeine-free, hydrating, and can help curb hunger pangs. Feel free to enjoy them hot or cold, based on your preference.

3. Black Coffee

If you’re a coffee lover, you’ll be glad to know that black coffee is generally considered acceptable during intermittent fasting. However, be cautious not to add cream, sugar, or artificial sweeteners, as they can break your fast. Enjoy your cup of joe plain or with a splash of unsweetened almond milk.

4. Green Tea

Green tea contains antioxidants and offers a mild caffeine boost. It can help boost your metabolism and may aid in fat burning. Sip a cup of green tea for a healthy and enjoyable beverage during your fasting window.

5. Matcha Latte

A matcha latte can be a great choice if you prefer a creamier and slightly sweet option. To make a delicious matcha drink, start with unsweetened almond & coconut milk as your ground. Then, whisk in some high-quality matcha powder. Remember to avoid sweeteners or syrups to keep it fasting-friendly.

6. Vegetable Juice

Freshly squeezed vegetable juices can be a nutrient-dense addition to your fasting routine. Opt for low-sugar vegetables like cucumber, celery, spinach, kale, and a touch of lemon juice for flavor. Just be mindful of portion sizes and avoid store-bought juices containing added sugars.

7. Bone Broth

Bone broth is hydrating and a good protein, collagen, and minerals source. Sip on a warm cup of homemade or store-bought bone broth during your fasting window for a nourishing and savory drink.

8. Coconut Water

If you’re looking for a natural source of electrolytes, coconut water is a fantastic choice. It’s low in calories and provides essential minerals like potassium, magnesium, and sodium. Ensure you select an unsweetened and pure variety without any added sugars.

9. Sparkling Water

Sometimes, you might crave a fizzy drink during fasting. Sparkling water can be a fantastic alternative to soda or sugary carbonated beverages. Choose plain or naturally flavored options without added sweeteners or artificial additives.

10. Infused Water

Infused water adds flavor to plain water without counting calories or breaking your fast. Experiment with combinations like lemon and mint, cucumber and lime, or berries and herbs. Prepare a pitcher of infused water and enjoy it throughout the day.


There are benefits and drawbacks to consuming intermittent fasting coffee. However, it’s important to remember that there is no “right” or “wrong” regarding your personal health decisions. Consider your reasons for drinking coffee while fasting, and decide what’s suitable for you after carefully considering all the facts.

William is from Canada, he is passionate nutrition & wellness writer. William understands that the topic of wellness is still not well understood, so his goal is to enlighten and teach people how to live healthier and happier in their bodies.

Intermittent fasting 101Intermittent fasting drinkIntermittent fasting videos