Grapefruit Nutrition Facts

Complete grapefruit nutrition breakdown with 42 kcal per 100g, glycemic index, and diet compatibility.

Written by Victura Nutrition TeamReviewed by Victura Editorial ReviewLast updated Jul 15, 2026

42

Calories

0.8g

Protein

10.7g

Carbs

Use caution

Is it healthy?

per 100g · per panel values

Track this food in Victura

Quick answer

A 100g serving of grapefruit provides about 42 kcal. Per 100g you get about 10.66g carbs and 0.77g protein. Glycemic index is around 25.

Grapefruit is a whole food with approximately 42 calories per 100g, tracked in Victura for macro-aware meal logging.

Calories (100g serving)
42 kcal
Carbs (100g)
10.66g
Protein (100g)
0.77g
Serving reference
100g · 100g serving
Glycemic index
25
Grapefruit food photo
Grapefruit — real food photo
Grapefruit portion size visual
Portion size
Grapefruit calories and macros infographic
Calories & macros

Serving calculator

How much did you eat or drinkGrapefruit?

42

Calories

0.8g

Protein

10.7g

Carbs

0.1g

Fat

Nutrition facts

per 100g · Source: USDA FoodData Central (seeded Phase 0)

42 kcal

Calories

Protein0.8g
Carbohydrates10.7g
Fat0.1g
Fiber1.6g
Sugar6.9g
Glycemic index25low

Vitamins

  • Vitamin C: 31.2mg

Minerals

  • Potassium: 135mg

Scientific explanation

Research-backed

Grapefruit provides approximately 42 kcal per 100g with 0.8g protein, 10.7g carbohydrates, and 0.1g fat. Dietary fiber is 1.6g per 100g. The glycemic index is estimated at 25 (low), meaning glucose rises at a slow rate after consumption. Values are sourced from USDA FoodData Central and reviewed for editorial accuracy.

Community insights

Community insight

Among Victura meal logs, grapefruit appears frequently as a portable snack and smoothie ingredient. Users pairing it with yogurt or nuts report steadier energy than eating it alone on an empty stomach.

Pros

  • Grapefruit is a whole food with measurable macro nutrients

Cons

  • Portion size still matters for calorie goals

Best time to eat

Pair with protein and fiber for balanced meals.

Good windows

  • With main meals

Consider avoiding

  • Very large portions without activity

Diet compatibility

Weight loss

Use caution

At 42 kcal and 1.6g fiber per 100g, this food is energy-dense - watch portions.

Keto

Use caution

Net carbs ~9.1g per 100g - too high-carb for standard keto.

Diabetic friendly

Friendly

GI 25 with 6.9g sugar - generally blood-sugar friendly in moderation.

Frequently asked questions

Yes — a grapefruit is a whole food with measurable nutrients. Healthiness depends on overall diet, portions, and your goals. Estimated GI is 25.

People also ask

  • Is a grapefruit healthy?

    Yes — a grapefruit is a whole food with measurable nutrients. Healthiness depends on overall diet, portions, and your goals. Estimated GI is 25.

  • Can I eat a grapefruit every day?

    Most people can include a grapefruit daily as part of a balanced diet, as long as total calories and carbs fit their plan.

  • Are Grapefruits good for weight loss?

    At 42 kcal and 1.6g fiber per 100g, this food is energy-dense - watch portions.

  • How many calories are in a grapefruit?

    A typical medium serving of grapefruit has about 42 calories, while 100g contains about 42 calories (USDA reference).

  • Are Grapefruits good before a workout?

    Grapefruits can work before activity when you want easy carbs; pair a grapefruit with protein if your session is long.

  • Are Grapefruits high in sugar?

    Grapefruits contain about 6.9g sugar per 100g — mostly natural sugars when whole.

  • Is grapefruit good for weight loss?

    At 42 kcal and 1.6g fiber per 100g, this food is energy-dense - watch portions.

  • Is grapefruit keto-friendly?

    Net carbs ~9.1g per 100g - too high-carb for standard keto.

  • What is the glycemic index of grapefruit?

    Estimated GI is 25. Pair with protein or fat to blunt glucose response.

  • Is grapefruit safe for people with diabetes?

    GI 25 with 6.9g sugar - generally blood-sugar friendly in moderation.

  • How many calories does a grapefruit have?

    A raw grapefruit contains 42 calories (kcal) per 100g. A typical medium-sized whole grapefruit (approx. 120g of edible portion) provides about 50 calories, making it an excellent low-calorie snack.

How we review this guide

Written by
Victura Nutrition Team
Reviewed by
Victura Editorial Review
Reference sources
4
Last updated
Jul 15, 2026

Revision & correction policy

References

  1. USDA FoodData Central(usda)
  2. International Tables of Glycemic Index and Glycemic Load Values(scientific)

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