Is watermelon good to break a fast?

It is gentle and hydrating, but light on protein. Pair it with yogurt, eggs or nuts.

Does watermelon break ketosis?

Probably, in a typical portion. A cup has about 11 g of carbohydrate.

Does watermelon water break a fast?

Water with fruit removed has very few calories. Blended watermelon juice is a sugary drink.

How many calories are in a slice of watermelon?

A large wedge has roughly 80 to 90 calories, a cup of cubes about 46.

Does Watermelon Break a Fast? Yes

Reviewed by the FastTrack team · Updated June 2026

Short answer: Yes

Yes, watermelon breaks a fast. A cup of diced watermelon has about 46 calories and 9 g of sugar, enough to raise blood sugar and insulin. It is light and hydrating, which makes it a good first food rather than a fasting snack.

Calories	~46 kcal per cup
Breaks a weight-loss fast?	Yes
Breaks ketosis?	Partial
Breaks autophagy?	Yes
Insulin impact	Moderate

Why watermelon ends the fast

Watermelon is mostly water, yet its sugar is absorbed quickly. A large slice can carry 15 to 20 g of sugar, a clear signal for insulin and the end of the fasted state.

Breaking a fast with watermelon

After a long fast, a few pieces of watermelon are gentle on the stomach and help with fluids. On its own it brings almost no protein, so follow it with a real meal. Watermelon-infused water with the fruit removed has only a few calories.

How much is safe

Keep watermelon for your eating window. A cup is a reasonable portion; larger amounts add up in sugar.

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Frequently asked questions

Is watermelon good to break a fast?: It is gentle and hydrating, but light on protein. Pair it with yogurt, eggs or nuts.
Does watermelon break ketosis?: Probably, in a typical portion. A cup has about 11 g of carbohydrate.
Does watermelon water break a fast?: Water with fruit removed has very few calories. Blended watermelon juice is a sugary drink.
How many calories are in a slice of watermelon?: A large wedge has roughly 80 to 90 calories, a cup of cubes about 46.