Does coconut oil break ketosis?

No, it is pure fat and supports ketosis.

Is coconut oil in coffee fasting?

Adding it makes a fat fast, not a true fast.

Does coconut oil raise insulin?

No, fat does not meaningfully raise insulin.

Does Coconut Oil Break a Fast?

Reviewed by the FastTrack team · Updated June 2026

Short answer: Yes

Coconut oil breaks a fast. Like other oils it is pure fat at about 120 calories per tablespoon, so it ends a calorie or autophagy fast even though it does not raise insulin.

Calories	~120 kcal per tbsp
Breaks a weight-loss fast?	Yes
Breaks ketosis?	No
Breaks autophagy?	Yes
Insulin impact	None

Why coconut oil breaks a fast

Coconut oil is concentrated fat, around 120 calories per tablespoon, with no carbohydrate or protein. It will not raise insulin or break ketosis, but the calories break a fast defined by calorie restriction and they stop autophagy. Like MCT oil, it is sometimes added to coffee for a fat fast, which is not a true fast.

Ketosis yes, fasting no

If your only goal is staying in ketosis, coconut oil is compatible. If your goal is autophagy or a calorie-free fast, it breaks it. Keep coconut oil for cooking during your eating window when you want the cleanest fast.

How much is safe

A tablespoon adds about 120 calories, so save coconut oil for your eating window during a strict fast.

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Frequently asked questions

Does coconut oil break a fast?: Yes, its calories break a calorie or autophagy fast.
Does coconut oil break ketosis?: No, it is pure fat and supports ketosis.
Is coconut oil in coffee fasting?: Adding it makes a fat fast, not a true fast.
Does coconut oil raise insulin?: No, fat does not meaningfully raise insulin.