The Best Fasting-Friendly Drinks (Besides Water and Coffee)

Hour 14 of a fast, and plain water has lost its appeal. Another black coffee might push past safe caffeine limits. This scenario plays out daily for millions of intermittent fasters who believe their drink choices end there; but that’s a myth.

Science supports nine different beverages that maintain a fasted state while delivering real benefits. Some boost autophagy, others crush hunger, and a few provide steady energy without breaking the fast. This guide cuts through the confusion with research-backed answers on what actually works.

Discover which drinks support specific fasting goals, how to time them strategically, and which popular options secretly sabotage progress.

What Actually Breaks a Fast? The Science Explained

Before diving into drink options, you need to understand what breaks fast. Johns Hopkins neuroscientist Mark Mattson explains that fasting triggers metabolic switching; your body exhausts sugar stores and starts burning fat.

Generally, drinks with fewer than 5 calories and no insulin response are safe. However, your fasting goal matters. If you’re fasting for autophagy (cellular cleanup), you need zero calories. For metabolic benefits like fat burning and insulin control, drinks under 50 calories may work.

Research from Johns Hopkins shows ketones are produced 8-12 hours after fasting starts. This metabolic switch is what you want to preserve. The drinks below support this process rather than disrupting it.

Use our AI assistant to get personalized fasting recommendations based on your specific goals.

Read Apple Cider Vinegar During a Fast: Benefits and Best Practices

1. Green Tea – The Autophagy Amplifier

Green tea isn’t just a beverage; it’s an autophagy powerhouse. At just 2-3 calories per cup, it won’t break your fast. More importantly, it may enhance the cellular benefits you’re seeking.

The magic ingredient is EGCG (epigallocatechin gallate), a powerful polyphenol. Research suggests green tea can enhance autophagy, particularly in liver and brain cells, by activating specific cellular pathways linked to longevity.

Green tea also boosts fat oxidation. The combination of caffeine and catechins increases your metabolic rate, helping you burn stored fat more efficiently during fasting windows. You also get L-theanine, an amino acid that provides calm alertness without jitters.

Try this: Start with 1-2 cups during your fasting window. Matcha is even more concentrated, offering 6-10 calories per cup with up to 10 times the antioxidants of regular green tea.

2. Herbal Teas – The Comfort Collection

Herbal teas offer zero calories and zero caffeine. This is perfect for evening fasting or caffeine-sensitive individuals. Don’t dismiss them as just warm water. Studies show six popular herbal teas, including ginger and hibiscus, can modulate autophagic pathways.

Each variety serves specific purposes:

Peppermint reduces nausea and supports digestion. It is helpful if you’re experiencing fasting discomfort.

Chamomile promotes relaxation and better sleep, crucial since poor sleep disrupts fasting benefits.

Ginger fights inflammation and settles your stomach during longer fasts.

Hibiscus stands out for metabolic support. Research published in the Journal of the Science of Food and Agriculture found hibiscus tea can enhance insulin sensitivity and reduce the risk of metabolic diseases.

Rooibos contain unique antioxidants that may lower blood pressure and oxidative stress.

Rotate these teas throughout your fasting window to prevent boredom while targeting different health benefits.

Read Can You Use Stevia or Monk Fruit While Fasting?

3. Sparkling Water – The Fizzy Fix

If you are missing the satisfaction of a fizzy drink, sparkling water delivers zero calories while helping with hunger suppression. The carbonation creates stomach fullness, making it easier to push through difficult fasting periods.

Plain carbonated water, mineral water like Perrier, or homemade versions from a CO2 maker all work perfectly. You can add a squeeze of lemon or lime. Both are virtually calorie-free at about 1-2 calories per squeeze.

Critical warning: Avoid flavored sparkling waters with hidden sweeteners. Many brands add “natural flavors” that may trigger insulin responses in sensitive individuals. Read labels carefully and stick to plain versions during fasting windows.

4. Bone Broth – The Modified Fast Option

Bone broth occupies unique territory. At 30-40 calories per cup, it technically breaks a strict fast. However, a 2025 clinical trial studied the Bone Broth Diet combining bone broth with intermittent fasting in 100 adults with obesity, finding it provides essential collagen, amino acids, and electrolytes while maintaining aspects of a fasted state.

This makes bone broth ideal for specific situations:

Extended fasts (24+ hours) where you need sustained electrolytes and minerals.

Fasting headaches which increase with fasting duration. The sodium and nutrients in bone broth can prevent this common side effect.

Gut health support through glycine, proline, and collagen that help repair intestinal lining.

Think of bone broth as a bridge between strict water fasting and eating. It contains minimal carbohydrates, keeps you in fat-burning mode, and provides amino acids that support cellular repair.

Learn more about different fasting schedules with our fasting tracker to determine when bone broth makes sense for your protocol.

Read The Beginner’s Guide to Fasting for Men Over 50

5. Electrolyte Water – The Hydration Hero

Electrolyte balance becomes critical during fasting. Sodium deficiencies can cause muscle cramping, brain fog, fatigue, and even insulin resistance. You’re not eating foods that normally provide minerals, so supplementation matters.

Add a pinch of pink Himalayan salt or sea salt to your water. This provides sodium, potassium, and trace minerals without calories. Drinking electrolyte water to thirst prevents both dehydration and the dangerous consequences of overhydration.

Zero-sugar electrolyte packets work too, but avoid sports drinks with added sugars. They’ll spike insulin and end your fast immediately.

Practical approach: Start with 1/4 teaspoon of sea salt in 16 oz water. Adjust based on how you feel. If you experience headaches, fatigue, or muscle cramps, increase your electrolyte intake.

6. Apple Cider Vinegar Water – The Metabolism Supporter

Apple cider vinegar (ACV) diluted in water has become popular among fasters for good reason. At 1-2 teaspoons per glass, it contains virtually zero calories when properly diluted.

Some people find that drinking ACV water helps them stay hydrated and prevent cravings during fasts. Early research suggests it may help with blood sugar regulation, though more studies are needed.

Important: Always dilute ACV. 1 teaspoon in 8-16 oz water. Drink it through a straw to protect tooth enamel from the acidity. Never consume it straight, as the acid can damage your esophagus and teeth.

Choose raw, unfiltered ACV with “the mother” for maximum benefit. The cloudiness indicates beneficial bacteria and enzymes are present.

Read Intermittent Fasting and Hydration: Best Practices Beyond Water

7. Black Tea – The Energy Booster

Black tea contains more caffeine than green tea but less than coffee, making it perfect for sustained energy without over-caffeination. At 2-5 calories per cup, it fits comfortably within fasting parameters.

Black tea provides theaflavins: powerful antioxidants formed during the fermentation process. While green tea has higher polyphenol content, black tea delivers its own unique benefits for cardiovascular health.

Popular varieties like English Breakfast offer robust flavor, while Earl Grey adds bergamot for a citrus note. Both work equally well for fasting.

Timing tip: Use black tea in the morning for energy, then switch to herbal teas in the afternoon to avoid sleep disruption from caffeine.

8. Oolong Tea – The Middle Ground

Oolong tea sits between green and black tea in processing, offering a balanced caffeine level and unique flavor profile. It’s partially fermented, creating a distinct taste that many find more interesting than green tea but smoother than black tea.

Research indicates oolong tea can modulate autophagic pathways, similar to green tea. It may also enhance fat oxidation, making it particularly useful for weight-loss-focused fasters.

At 2-3 calories per cup, oolong provides variety in your fasting drink rotation without compromising your metabolic state.

9. Lemon Water – The Simple Refresher

Sometimes simple is best. A squeeze of lemon in water adds approximately 6 calories; well within the “safe zone” for most fasting protocols. It provides vitamin C, adds flavor variety, and can make plain water more appealing during long fasting windows.

The key is moderation. Half a lemon squeezed into 16 oz water gives you flavor without significant caloric impact. Never add honey, sweeteners, or large amounts of lemon that would push calories higher.

Lime works equally well and offers similar benefits at virtually the same calorie count.

Drinks to Avoid During Your Fast

Knowing what to avoid is as important as knowing what works. These drinks will break your fast:

Any drink with sugar like juice, sweetened tea, regular soda. It breaks your fast immediately by spiking insulin.

Milk or cream introduces calories and fat. Even small amounts in coffee can disrupt fasting for those seeking autophagy benefits.

Diet sodas present a gray area. While technically low-calorie, artificial sweeteners may negatively affect gut bacteria and potentially trigger insulin responses in sensitive individuals.

Alcohol contains calories and disrupts your metabolic state, making it incompatible with any fasting protocol.

Protein shakes are designed to end a fast, not maintain it. Save these for your eating window.

Read What Can You Drink While Fasting? A Simple Beginner’s Guide

Your Fasting Journey Just Got Easier

You now have nine science-backed drink options beyond water and coffee. Each serves different purposes; green tea for autophagy, bone broth for extended fasts, herbal teas for comfort, electrolyte water for mineral balance. The key is zero calories, no insulin response, and strategic rotation to keep fasting sustainable long-term.

Johns Hopkins Medicine emphasizes that successful fasting requires finding approaches you can maintain. Variety in your drink choices makes that possible.

Try our AI-powered fasting assistant to get personalized drink recommendations based on your fasting schedule and goals. Use our fasting tracker to monitor your progress, log which drinks work best, and stay consistent with your intermittent fasting routine.