Will cinnamon in my coffee break my fast? The definitive answer for intermittent fasting

January 3, 2026 •

4 min read

One teaspoon of ground cinnamon contains approximately 6 to 7 calories, a minuscule amount that is unlikely to trigger a metabolic response strong enough to break a fast. This makes adding a sprinkle of cinnamon to your coffee a popular strategy for those asking, 'will cinnamon in my coffee break my fast?'.

Quick Summary

A small dash of cinnamon in black coffee generally does not break a fast, as its minimal calorie and carb content has little impact on metabolic function. The key is avoiding caloric additives like sugar or milk. The type and amount of cinnamon used are crucial factors to consider during fasting periods.

Key Points

Low Calorie Impact: A typical teaspoon of cinnamon contains less than 7 calories and minimal carbs, which is too little to trigger a metabolic response that would break a fast.
Black Coffee Only: The fast is broken by caloric additives like milk, cream, sugar, or honey, not the cinnamon itself. Stick to black coffee for a successful fast.
Blood Sugar Regulation: Cinnamon has been shown to improve insulin sensitivity and help regulate blood sugar, which supports the metabolic goals of intermittent fasting.
Choose Ceylon for Regular Use: For daily or heavier consumption, opt for Ceylon cinnamon, which is low in coumarin and less likely to pose a liver health risk than the more common Cassia variety.
Moderation is Key: While a dash is fine, consuming more than two teaspoons of cinnamon could add enough calories to potentially interfere with some fasting benefits, especially autophagy.
Listen to Your Body: If you are particularly sensitive or aiming for a strict "clean fast" focused on autophagy, you might consider avoiding even the smallest additions, though for most, a sprinkle is safe.

Will cinnamon in my coffee break my fast? The definitive guide

For many who practice intermittent fasting, a morning cup of coffee is a crucial ritual. However, the strict rules of fasting can make adding anything to that coffee a confusing dilemma. The question, “will cinnamon in my coffee break my fast?” is a common one, and the good news for most fasters is a resounding no, with a few important caveats.

Why a sprinkle of cinnamon is generally safe for your fast

The primary reason a small amount of cinnamon won't break your fast comes down to its nutritional profile. Cinnamon is extremely low in calories, carbohydrates, and protein—the macronutrients that trigger an insulin response and shift your body out of a fasted state. Most experts agree that staying under a certain calorie threshold (often cited as 10-15 calories) will not disrupt the metabolic benefits of fasting, such as fat burning and insulin regulation. A typical teaspoon of ground cinnamon contains far less than that, making it a safe and flavorful addition.

Negligible calories: A single teaspoon has around 6.4 calories and minimal carbs (2.1g, with 1.4g being fiber), not enough to prompt a significant metabolic shift.
Supports metabolic health: Research indicates that cinnamon can improve insulin sensitivity and help regulate blood sugar, which are core goals of intermittent fasting.
Appetite control: Some studies suggest that cinnamon may have appetite-suppressing effects, helping you to manage cravings and extend your fasting window more comfortably.
Antioxidant benefits: Cinnamon is rich in antioxidants and has anti-inflammatory properties, potentially amplifying some of the health benefits of fasting.

The crucial distinction: What will break your fast

The real danger to your fast isn't the cinnamon, but what you might be tempted to add along with it. A black coffee with cinnamon is a fasted-state-friendly beverage, but the moment you introduce other caloric ingredients, you risk breaking your fast. This is a critical distinction for anyone serious about the process.

Sugar and syrups: Any form of sugar, honey, or flavored syrup will cause an insulin spike, immediately ending your fast. Even "natural" sugars count.
Milk and cream: Dairy products, including cow's milk and even high-fat heavy cream, contain lactose (a sugar), proteins, and calories that will disrupt your fast.
Bulletproof coffee additions: Ingredients like butter or MCT oil, while popular in ketogenic circles, add calories and end a traditional fast. While they may not spike insulin as much as sugar, they provide fuel that halts your body's reliance on stored fat for energy.

Cassia vs. Ceylon cinnamon and the liver health concern

Not all cinnamon is created equal. The two main types are Cassia and Ceylon, and understanding the difference is important, especially if you plan to use it regularly.

Cassia vs. Ceylon Cinnamon


Feature	Cassia Cinnamon	Ceylon Cinnamon
Origin	China, Indonesia, Vietnam	Sri Lanka (historically Ceylon)
Taste	Strong, pungent, spicy	Milder, sweeter, more delicate
Appearance	Thick, single-layered, reddish-brown bark	Thin, paper-like, multiple layers, light tan color
Coumarin Content	High	Very Low
Price	Inexpensive, widely available	More expensive, less common
Liver Concern	Potential risk of liver damage with high intake over time due to coumarin	Very low risk due to minimal coumarin content

Cassia cinnamon, the most common and inexpensive variety, contains a compound called coumarin. In high doses, coumarin can be toxic to the liver. While a small amount for your coffee is perfectly safe, heavy daily use of Cassia could become a concern over the long term. Ceylon cinnamon, also known as "true cinnamon," contains very little coumarin, making it a safer option for frequent consumption. For most people using just a dash, the difference is not critical, but for those who are cautious or consume more, opting for Ceylon is a wise choice.

Conclusion

Adding a small, reasonable amount of cinnamon (up to 1 teaspoon) to your black coffee will not break your fast and may even offer supporting health benefits, like blood sugar regulation. The key is to keep your coffee truly black, avoiding any caloric additions like sugar, milk, or flavored syrups. For peace of mind with regular use, consider choosing Ceylon cinnamon to minimize coumarin intake. By sticking to this simple rule, you can enjoy a flavorful cup of coffee without compromising your fasting goals, from weight loss to cellular repair.

A note on fasting goals

It's important to remember that fasting can have different goals, such as weight loss or maximizing autophagy (cellular cleansing). For weight loss, a few calories might be acceptable. For maximizing autophagy, some practitioners advise a "clean fast" with nothing but water. For those purposes, even a minimal calorie amount might be avoided. Ultimately, a standard intermittent fast for weight management is highly unlikely to be affected by a small amount of cinnamon.

Frequently Asked Questions

Most experts agree that up to one teaspoon of cinnamon is safe. This amount contains negligible calories and carbohydrates, and will not significantly impact your fasted state.

No, small amounts of cinnamon are not known to spike insulin. In fact, studies suggest that cinnamon can actually help improve insulin sensitivity and lower blood sugar levels, which aligns with fasting goals.

While you can add cinnamon, bulletproof coffee itself (which contains butter and MCT oil) contains calories and will break a traditional fast. The fats provide energy, stopping your body from relying on its fat stores.

For regular or daily use, Ceylon cinnamon is the safer choice as it contains very low levels of coumarin, a compound found in higher amounts in Cassia cinnamon that can cause liver issues in large doses over time.

If you use slightly more than a teaspoon, it is unlikely to have a major effect, but moderation is advised. The threshold for breaking a fast is typically low (around 10-15 calories), so a large amount could be counterproductive.

While some very strict protocols suggest any calories might impact autophagy, consuming a small amount of cinnamon is widely considered safe and unlikely to inhibit the process significantly.

Yes, cinnamon has some appetite-suppressing qualities and its flavor can help satisfy cravings for sweetness without sugar, which can make sticking to your fast easier.

Many spices like nutmeg, ginger, and turmeric are also very low in calories and can be added in small amounts without breaking a fast.