What to Drink During Intermittent Fasting (Complete Guide)

Medically reviewed by Christian Jacobs, MSc

So, you’ve decided to start intermittent fasting. Great choice! But now the question hits:

“What can you actually drink during intermittent fasting without breaking your fast?”

Don’t worry, we’ve got you covered. In this guide, you’ll learn exactly what drinks are safe, which ones to avoid, and even discover delicious zero-calorie drinks that make fasting easier.

Can You Eat or Drink During Intermittent Fasting?

When you’re fasting, the golden rule is simple: anything with calories technically breaks your fast.

Here’s why: the moment your body detects calories (even from a drink), it begins to process them for energy. This triggers insulin release, which interrupts the fasting state.

That’s why zero-calorie drinks are the safest option. They won’t provide your body with energy, so your system continues burning stored fat for fuel,exactly what you want while fasting.

The good news? There are plenty of drinks that fit the bill. Let’s go through them one by one.

✅ The Best Drinks During Intermittent Fasting

#1: Water

Water is your best friend during fasting. It’s 100% calorie-free, keeps you hydrated, and even helps reduce hunger.

Aim for at least 2 liters per day, or more if you’re active. Sparkling water is also fine if you prefer bubbles.

#2: Black Coffee

Coffee has a love-hate reputation, but the truth is: black coffee won’t break your fast.

• It’s virtually calorie-free

• Packed with antioxidants

• Can suppress appetite

• Linked to reduced risk of diabetes, Alzheimer’s, and Parkinson’s

Stick to plain black coffee, no sugar, milk, or cream. Too much caffeine, however, may cause jitters or heart strain, so keep it moderate.

#3: Green Tea

Like coffee, green tea is calorie-free and full of antioxidants.

Benefits include:

• Improved blood sugar control

• Boosted fat burning

• Increased metabolism

Aim for 3–6 cups daily for maximum benefits.

#4: Broth (Bone Broth or Vegetable Stock)

A light broth can be a lifesaver if you feel weak or headache-prone in the early days of fasting.

While broth contains a small amount of calories, it’s often considered negligible for fasting benefits—especially homemade bone broth rich in minerals.

#5: Apple Cider Vinegar

When diluted with water, apple cider vinegar can aid digestion and help manage blood sugar—without breaking your fast.

#6: Kombucha (Unsweetened)

Fermented teas like kombucha can be tricky. Choose unsweetened versions to avoid extra sugars. Best enjoyed during your eating window, though technically calorie-free versions are fast-safe.

#7: Sparkling Water

Carbonated water (a.k.a. club soda or seltzer) is a refreshing, calorie-free option. It also helps curb hunger cravings.

#8: Diet Sodas (Zero-Calorie Soft Drinks)

Technically allowed, since they’re calorie-free. But beware of artificial sweeteners—they may cause insulin spikes in sensitive people. Best used sparingly.

#9: Zero-Calorie Energy Drinks

If plain water feels boring, sugar-free energy drinks (like Red Bull Light) are an option. They provide caffeine, which can improve focus and curb hunger.

Stick to one per day max to avoid overstimulation.

🚫 Drinks to Avoid While Fasting

Not everything is allowed. Here’s what will definitely break your fast:

• Sugary drinks (soda, fruit juice, sweetened tea/coffee)

• Alcohol (calories + disrupts metabolism)

• Milk & creamers (yes—even small amounts break fasting)

• Smoothies & protein shakes (save for eating windows)

  
  

Even natural sweeteners like honey or stevia can interfere for some people. When in doubt, save it for your eating period.

Can You Juice Fast While Intermittent Fasting?

Juice fasting (a diet of pressed vegetable and fruit juices) is a different method than intermittent fasting. While juices are healthy, they contain natural sugars and calories, which end your fast.

If you enjoy juices, keep them for your eating window—or opt for mostly vegetable-based juices with minimal fruit to avoid sugar spikes.

Can You Take Supplements While Fasting?

Supplements are best taken during your eating window, since some contain calories or require food for proper absorption.

• Water-soluble vitamins (like vitamin C) can sometimes be taken on an empty stomach

• Fat-soluble vitamins (like vitamin D) should always be taken with food

When in doubt, time your supplements with meals.

Can You Take Medication While Fasting?

This depends on your prescription.

• Many pills (like aspirin) contain negligible calories and won’t affect your fast.

• Some medications must be taken with food to avoid stomach irritation or to boost absorption.

Always consult your doctor before combining fasting with medication.

Final Thoughts

Intermittent fasting is one of the simplest lifestyle changes for weight loss, better energy, and improved health.

But the key to success lies in knowing what you can and can’t drink while fasting. Stick to zero-calorie beverages like water, black coffee, and green tea, and avoid sugar, alcohol, and calorie-rich drinks.

Even if you slip up, remember: fasting is a learning process. Stay consistent, and your body will thank you.

Frequently Asked Questions About Intermittent Fasting Drinks

Does coffee break intermittent fasting?

Black coffee (without milk, cream, or sugar) does not break your fast. It’s calorie-free and can even reduce hunger. Adding milk, sugar, or flavored syrups will end your fasting state.

Can you drink tea while intermittent fasting?

Yes, unsweetened tea like green tea, black tea, or herbal tea is safe during fasting. Avoid adding honey, sugar, or milk, as these contain calories and will break your fast.

Is sparkling water allowed during fasting?

Absolutely. Sparkling water (seltzer, club soda) is calorie-free and perfectly safe. It can also help suppress hunger.

Do artificial sweeteners break a fast?

Zero-calorie sweeteners (like aspartame, sucralose, or stevia) usually don’t contain calories. However, some people may still experience an insulin response. Use them sparingly if possible.

Can I drink diet soda while fasting?

Technically yes—diet sodas contain no calories. But they’re best in moderation since artificial sweeteners may affect cravings or gut health.

Can I drink alcohol while intermittent fasting?

No. Alcohol contains calories and will break your fast immediately. It also disrupts fat burning and recovery, so it’s best avoided during fasting hours.

Is bone broth allowed while fasting?

Bone broth contains small amounts of calories and protein. While some strict fasters avoid it, many include it because the calories are minimal, and it helps with electrolytes and hunger.

Can supplements break a fast?

Some supplements are fine (like electrolytes, magnesium, or vitamin C), but those with calories, sugar, or oils will break your fast. To be safe, take supplements during your eating window.