Can I have bone broth on a 72 hour fast? Navigating modified vs. strict fasting

November 3, 2025 •

4 min read

While the strictest interpretation of fasting forbids any calories, many people use nutrient-dense liquids to support their health goals during a prolonged fast. The question, 'Can I have bone broth on a 72 hour fast?', therefore requires an understanding of different fasting methodologies and your ultimate objectives.

Quick Summary

Bone broth provides electrolytes and nutrients, but technically breaks a strict, calorie-free fast intended for maximum autophagy. For modified fasts aimed at weight loss or gut health, it can manage hunger and sustain energy without disrupting ketosis.

Key Points

Strict Fasting vs. Modified Fasting: Bone broth technically breaks a strict, zero-calorie fast due to its caloric content, but is a key component of modified fasting protocols.
Supports Electrolyte Balance: During prolonged fasts, bone broth can replenish essential minerals like sodium and potassium, preventing common side effects like headaches and fatigue.
Promotes Gut Health: Rich in collagen and gelatin, bone broth helps to soothe and repair the gut lining, an effect that is enhanced during a digestive reset.
Manages Hunger: The satisfying, savory flavor and protein content of bone broth help to curb hunger and make a 72-hour fast more sustainable.
Maintains Ketosis: Bone broth is low in carbohydrates and does not significantly spike insulin, allowing the body to remain in a fat-burning state.
Quality Matters: Whether homemade or store-bought, choosing a high-quality bone broth from organic, grass-fed sources with minimal additives is essential for maximizing benefits.
Used for Breaking the Fast: Even those on a strict fast can use bone broth as a gentle and nutrient-rich way to break their fast and prepare the digestive system for solid food.

Understanding the Goals of a 72-Hour Fast

A 72-hour or three-day fast is a form of prolonged fasting that can offer significant metabolic and cellular benefits. The physiological state your body enters during a fast is a key determinant in whether bone broth is permissible. Fasting objectives generally fall into two main categories: strict, water-only fasts for maximum autophagy, or modified fasts for benefits like weight loss and gut health.

The Strict Fasting Perspective

For fasting purists, the rule is simple: any caloric intake breaks the fast. Bone broth, containing 40–50 calories per cup, technically falls into the category of a fast-breaking food. This is particularly relevant if your primary goal is maximizing autophagy, the process of cellular cleansing that is amplified during extended periods without calories. The intake of proteins and fats, however minimal, can signal to the body that food is available, thereby down-regulating this specific cellular process.

The Modified Fasting Perspective

For many, especially those new to prolonged fasting, a modified approach is more sustainable and beneficial. In this context, bone broth is not only allowed but highly recommended. A modified bone broth fast allows you to sustain the fast longer by managing hunger, balancing electrolytes, and providing crucial nutrients that can be depleted during water-only fasts. This can prevent side effects like headaches and fatigue, making the process more comfortable.

Key Benefits of a Modified Bone Broth Fast

Incorporating bone broth into a 72-hour fast can offer several advantages, especially when compared to a water-only approach:

Replenishes Electrolytes: Extended water-only fasting can lead to electrolyte imbalances. High-quality bone broth is a natural source of essential minerals like sodium, potassium, and magnesium, which helps maintain balance and prevent weakness.
Supports Gut Health: Bone broth is rich in collagen, gelatin, and amino acids like glycine and glutamine. These compounds can help soothe and repair the gut lining, a process that can be particularly effective during a fasting period when the digestive system is at rest.
Curbs Hunger Pangs: The protein and rich, savory flavor of bone broth promote satiety, helping to reduce intense hunger and cravings that might otherwise lead to ending the fast prematurely.
Maintains Ketosis for Fat Loss: Since bone broth is very low in carbohydrates, it will not spike insulin levels. This means your body can remain in a state of ketosis, burning stored fat for energy, which is a key goal for many fasters.

Choosing the Right Bone Broth for Your Fast

To reap the maximum benefits and avoid unwanted additives, the quality of your bone broth is crucial.

Homemade vs. Store-Bought

Homemade Bone Broth: Offers the most control over ingredients and quality. Made by simmering bones, water, and herbs for 12-24 hours or more, it ensures maximum nutrient extraction and avoids fillers.
Store-Bought Bone Broth: Convenient but requires careful label reading. Look for products made from grass-fed or organic bones, with simple ingredients and no added sugar, yeast extract, or artificial flavorings.

What to Look For

Protein Content: Aim for a bone broth with at least 8-10 grams of protein per cup. A high protein content is a good indicator of a nutrient-dense broth.
Sodium Levels: Check the sodium content, as some store-bought brands can be very high. If you are adding extra salt for electrolytes, you will want a lower-sodium base.
Gelling: Quality bone broth will often gel when refrigerated due to its high collagen content. This is a sign of a properly made, nutrient-rich product.

How to Conduct a Bone Broth Supported 72-Hour Fast

For a structured modified fast, a simple protocol involves sipping bone broth throughout the fasting window:

Preparation (1-2 days prior): Reduce processed foods, sugar, and carbs to ease your body into the fasting state. Hydrate well.
During the Fast: Consume 5-8 cups of bone broth daily. You can space this out every 2-3 hours to manage hunger and energy levels. Supplement with plenty of plain water and herbal tea.
Breaking the Fast: Ease back into eating gradually. Start with small, easily digestible meals. Bone broth itself is an excellent first 'meal' to gently reintroduce nutrients and prepare your digestive system.

Strict Water Fast vs. Modified Bone Broth Fast


Feature	Strict Water Fast	Modified Bone Broth Fast
Caloric Intake	Zero Calories	Low-Calorie (from bone broth)
Primary Goal	Maximize Autophagy	Weight Loss, Gut Health, Sustainability
Nutrient Intake	None (besides water)	Electrolytes, Collagen, Amino Acids
Hunger Management	Intense Hunger is Common	Broth Curbs Hunger and Cravings
Electrolyte Balance	Requires supplementation	Maintained by bone broth
Sustainability	Challenging for beginners	Easier to adhere to for longer periods
Risk of Side Effects	Higher (headaches, fatigue)	Lower, due to nutrient support

Conclusion: Finding the Right Fast for Your Goals

Ultimately, whether you can or should have bone broth on a 72 hour fast depends entirely on your specific health objectives. For purists aiming for the maximum potential of autophagy, a water-only fast is the correct path. However, for those seeking the benefits of extended fasting—such as weight loss, improved gut health, and enhanced energy—in a more manageable and safer way, a modified bone broth fast is an excellent strategy. It provides essential nutrients, helps manage hunger, and supports a more sustainable fasting experience. Consulting with a healthcare professional before a prolonged fast is always recommended.

Properly Breaking the Fast

After a 72-hour fast, a gradual reintroduction of food is critical to avoid shocking your system. The first meal should be small, simple, and easy to digest. A cup of bone broth is one of the best ways to start this process, providing nutrients without overwhelming your digestive system. Other good options include fermented foods like yogurt or kefir, and soft, cooked vegetables. Overeating or consuming highly processed, sugary, or high-fat foods should be avoided immediately after the fast.

Frequently Asked Questions

Yes, for a strict fast, the caloric content of bone broth will technically inhibit the peak state of autophagy. If maximizing this cellular cleansing is your primary goal, a water-only fast is recommended.

During a modified fast, you can typically consume 5-8 cups of high-quality bone broth per day. Spacing these servings out every 2-3 hours helps manage hunger and sustain energy levels.

Yes, bone broth can be a beneficial tool for weight loss during a fast. It can help you feel full, manage hunger, and maintain ketosis without significantly impacting insulin levels.

Store-bought bone broth can be acceptable if you choose a high-quality product. Look for broths made from organic, grass-fed bones with minimal ingredients, no added sugar, and no yeast extract.

Headaches and fatigue are often caused by electrolyte imbalance. A modified fast with bone broth can help replenish electrolytes and prevent these symptoms, making the fast more manageable.

To make a clean homemade bone broth, simmer high-quality, grass-fed bones in filtered water with a small amount of apple cider vinegar for 12-24 hours. Minimal seasonings like salt can be added.

The best way to break the fast is gently. Begin with a serving of bone broth, followed by small portions of easily digestible foods like cooked vegetables, fermented foods, or eggs a couple of hours later.