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Calories in fruit

Calories in Watermelon

Watermelon contains 30 kcal per 100g — one of the most calorie-dilute fruits. Per cup cubed (~152g): 46 kcal with no meaningful fiber.

Nutrition by portion size

Portion kcal Carbs (g) Protein (g) Fat (g) Fiber (g)
1 cup cubed watermelon (~152g) 46 11 0.9 0.2 0.6
1 wedge (1/16 of melon, ~286g) 86 22 1.7 0.4 1.1
100g watermelon 30 8 0.6 0.2 0.4
1/2 cup balls 23 6 0.5 0.1 0.3
Glycemic index
72
High (≥70) — fast glucose rise

About these numbers

Watermelon is the most calorie-dilute popular fruit (30 kcal per 100g) — over 90% water. Despite a high GI (72), the glycemic load per cup is only 5 (low) because there's so little carbohydrate by weight. For volume eating during cuts, watermelon is essentially a free fruit.

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Frequently asked questions

How many calories in watermelon?
1 cup cubed: 46 kcal. 1 wedge: 86 kcal. Per 100g: 30 kcal — the lowest calorie density of common fruits.
Is watermelon good for weight loss?
Excellent. Lowest calorie density of common fruits (30 kcal/100g) combined with high water content provides satisfying volume per calorie. For volume eating during cuts, watermelon is essentially a free addition.
Does watermelon spike blood sugar?
Less than expected. Despite high GI (72), GL per cup is only 5 (low) because watermelon is mostly water with little carb mass per serving. For T2D, normal servings produce minimal glucose impact.
Watermelon vs other fruits for hydration?
Outstanding. 91% water content means 1 cup of watermelon provides ~140ml of water plus electrolytes (potassium, modest sodium). For hot-weather hydration, watermelon is one of the most efficient choices.
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