Grapefruit nutrition: calories, carbs, GI, protein, fiber, fats

by Victoria Mazmanyan | Last updated on October 27, 2023

Medically reviewed by Elen Khachatrian

Carbohydrates in Grapefruit

In this article, we will look at the nutrition of three types of grapefruit: raw pink and red grapefruit, raw white grapefruit, and grapefruit segments canned in juice. 

Carbohydrates per 100g

A 100g red grapefruit is comprised of over 10% carbohydrates, containing 10.66g of carbs.

White grapefruit is lower in carbohydrates, containing 2g fewer carbs in the same serving size.

Grapefruit segments canned in juice contain more carbs than white grapefruits but fewer carbs than red ones.

Carbohydrates per Serving Size

The average serving size of grapefruits that a person eats in one sitting is 154g or half a medium-sized grapefruit.

One average serving size of red and pink grapefruit contains 16.4g of carbs.

Since we consider the average serving size to be the same for different kinds of grapefruits, the comparison results will naturally stay the same.

Carbohydrate Breakdown

The carbohydrate content of red grapefruit consists of 65% sugars, 15% fiber, and 20% other carbohydrates. In other words, red grapefruit contains 6.89g of sugars, 1.6g of fiber, and 2.17g of other carbohydrates.

The primary sugar in grapefruit is sucrose, making up more than half of the sugar content. The other two sugars in this fruit are glucose and fructose, in similar amounts.

White grapefruit has a similar carbohydrate composition. However, grapefruit segments canned in juice are much lower in fiber, containing only 4% or 0.04g fiber.

Net Carbs

100g serving of grapefruit contains 9.06g of net carbs. Of this, 6.89g are made up of sugars, and the rest consists of other carbohydrates.

Soluble and Insoluble Fiber

The fiber content in grapefruit consists of 75% soluble (1.2g) and 25% insoluble fiber (0.4g) (1).

Soluble fiber slows down and improves digestion, while insoluble fiber helps with constipation.

Calories in Grapefruit

A 100g serving of red grapefruit provides 42 calories. This means that one average serving size, or half a grapefruit, contains 65 calories.

White grapefruit and grapefruit segments canned in juice are relatively lower in calories.

A 100g serving size of grapefruits provides only 2% of your daily calorie intake needs.

What Do 42 Calories or 100 Grams of Grapefruit Look Like?

Our team measured what 100 grams of grapefruit looks like to help you visualize its weight and calories. As you can see from the picture below, about one-third of grapefruit comprised 100 grams or 42 calories, which means one whole grapefruit is about 300 grams or about 126 calories. 

Remember that calorie numbers can vary depending on the grapefruits' size and ripeness.

Comparison to Other Fruits

Grapefruit is often compared to other popular citrus fruits, such as orange. To read more about this, visit our "Grapefruit vs. Orange" full comparison page.

In the table below, you can look at how grapefruits compare to other fruits regarding calorie content.

Burning Estimates

Using a method called Met or Metabolic Equivalent of a Task, we have calculated how much physical activity will burn the number of calories (65 cal) provided by one average serving size of a grapefruit (2, 3).

References

1. https://sci.washington.edu/info/forums/reports/FiberFacts.pdf
2. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4428382/
3. 2011 Compendium of Physical Activities

Author name: Victoria Mazmanyan

Education: General Medicine at YSMU

Last updated: October 27, 2023

Medically reviewed by Elen Khachatrian