Can you drink coffee while fasting?

Fasting sounds simple; stop eating for a while and that's it. But then comes the question: can I still have my coffee?

If you've ever skipped breakfast, you know the feeling. That first sip of coffee in the morning is delicious.

Some people say that black coffee is fine while fasting.

Others act like one drop of espresso ruins everything. What is the truth? Can you keep drinking coffee without breaking the fast?

Let's find out!

Does coffee break the fast?

The short answer: No, black coffee does not break your fast. It has no calories, no carbs, no protein—just water and caffeine.

As long as nothing is added to it, it will not trigger an insulin response or disrupt fat burning.

But fasting isn't always just about avoiding food. Some people fast for health, others to lose weight, and still others for religious reasons.

So whether coffee is “allowed” depends on the type of fasting you are doing.

Coffee and Different Types of Fasting

Intermittent Fasting (IF)

Intermittent fasting is all about eating within a certain window of time, such as 16:8 (fasting for 16 hours, eating for 8 hours). Black coffee is perfectly fine with this. In fact, it can help by reducing hunger and boosting metabolism.

As for bulletproof coffee (butter + coffee)? No. It has calories and breaks the fast.

Water fasting

On a strict water diet, coffee is technically not water, but most people still drink it because it doesn’t interfere with the benefits of fasting, such as autophagy (cell repair) and fat burning.

Religious fasting (Ramadan, Orthodox, etc.)

Religious fasting is strongly linked to spiritual beliefs and traditions and the rules can vary greatly depending on the faith and fasting period.

Ramadan (Islamic fasting)

During the holy month of Ramadan, Muslims fast from sunrise (Fajr) to sunset (Maghrib). During these hours, food and drink, including coffee, are not permitted.

However, many people drink coffee before sunrise (Suhoor) and after sunset (Iftar) to maintain their energy levels.

Christian fasting (Lent, Orthodox fasting)

Many Christian fasts, especially in the Orthodox tradition, require avoiding animal products or specific foods. Black coffee is usually permitted, especially if only solid foods are restricted.

Jewish Fasting (Yom Kippur, Tisha B'Av)

These are complete fasting days where no food or drink is consumed for 24 hours. Coffee is not allowed.

Hindu fasting (Ekadashi, Navratri, etc.)

Hindu fasting rules vary widely. Some fasts allow drinks such as coffee, while others allow only water.

If you are fasting for religious reasons, it is best to follow the specific guidelines of your faith or seek advice from a religious leader.

Effects of coffee during fasting

Suppresses appetite

Caffeine can help reduce hunger pangs, especially in the morning. It temporarily gives your brain the feeling that you are full.

Increases metabolism

Caffeine stimulates thermogenesis, which means your body burns slightly more energy. This can support fat loss, but don't expect miracles.

Promotes mental acuity

Many people feel more alert during fasting and coffee enhances that effect. It helps with focus and alertness, making fasting easier.

May cause stomach upset

Coffee on an empty stomach can cause acid reflux or irritation. If your stomach is prone to this, try a lighter roast or cold brew, which is less acidic.

What about additives in coffee?

Milk and cream

Even a little bit of milk contains calories and protein, which technically breaks the fast. If you're strict, leave it out. If you're flexible, a few drops won't ruin everything.

Sweeteners

• Sugar? Not an option. Calories break the fast.

• Artificial sweeteners? Opinions differ. Some don't affect insulin, others do. Safest bet: avoid them.

• Stevia? Usually fine. It’s natural and doesn’t cause an insulin spike.

MCT oil or butter

These contain calories and technically break the fast. Some people use them for keto fasting. If you are fasting for autophagy, you may want to skip them.

Frequently Asked Questions

Can I drink coffee all day while fasting?

Yes, but too much caffeine can lead to nervousness, dehydration and poor sleep. Limit it to a few cups a day.

Does decaffeinated coffee work the same way?

Yes. Decaf has almost no calories and does not break the fast.

What about cold brew?

Cold brew is fine. In fact, it is smoother and less acidic, making it easier on the stomach.

Does Coffee Affect Fasting Blood Sugar Tests?

Black coffee may cause a small, temporary rise in blood sugar levels in some people, but because it has no calories it does not break the fast.

Can I drink herbal tea instead?

Yes. Herbal teas such as peppermint or chamomile are fine during fasting.

Conclusion

Are you fasting and do you like coffee? Good news: black coffee does not break the fast. It helps against hunger, gives energy and makes fasting easier.

Keep it simple. No sugar, no milk, no fancy additives—unless your fast allows it.

Stick to the basics and you'll be fine.

Good luck with your fasting and enjoy your coffee!