Grapefruit vs. Watermelon

Nutrition comparison of Grapefruit and Watermelon


Ever wonder how your favorite foods stack up against each other in terms of nutrition?

We compared the nutritional contents of grapefruit versus watermelon (100g each) below using 2020 USDA and NIH data[1].

For a quick recap of significant nutrients and differences in grapefruit and watermelon:

  • Grapefruit has more beta-carotene than watermelon, however, watermelon contains more lycopene than grapefruit.
  • Grapefruit has more folate.
  • Grapefruit is an excellent source of Vitamin C.
Detailed nutritional comparison of grapefruit and watermelon is analyzed below. You can also visualize the nutritional comparison for a custom portion or serving size and see how the nutrition compares.

USDA sources for nutritional information: Grapefruit (Grapefruit, raw, pink and red, all areas) and Watermelon (Watermelon, raw) . Have a correction or suggestions? Shoot us an email.


Image of Grapefruit src
Image of Watermelon src

Calories and Carbs

calories

Watermelon and grapefruit contain similar amounts of calories - watermelon has 30 calories per 100 grams and grapefruit has 42 calories.

For macronutrient ratios, grapefruit is similar to watermelon for protein, carbs and fat. Grapefruit has a macronutrient ratio of 7:91:3 and for watermelon, 7:89:4 for protein, carbohydrates and fat from calories.

Macro Ratios from Calories:

Grapefruit Watermelon
Protein 7% 7%
Carbohydrates 91% 89%
Fat 3% 4%
Alcohol ~ ~

carbohydrates

Watermelon and grapefruit contain similar amounts of carbs - watermelon has 7.6g of total carbs per 100 grams and grapefruit has 10.7g of carbohydrates.

dietary fiber

Grapefruit has 300% more dietary fiber than watermelon - watermelon has 0.4g of dietary fiber per 100 grams and grapefruit has 1.6g of dietary fiber.

sugar

Watermelon and grapefruit contain similar amounts of sugar - watermelon has 6.2g of sugar per 100 grams and grapefruit has 6.9g of sugar.

Protein

protein

Watermelon and grapefruit contain similar amounts of protein - watermelon has 0.61g of protein per 100 grams and grapefruit has 0.77g of protein.

Fat

saturated fat

Both watermelon and grapefruit are low in saturated fat - watermelon has 0.02g of saturated fat per 100 grams and grapefruit has 0.02g of saturated fat.

Vitamins

Vitamin C

Grapefruit is an excellent source of Vitamin C and it has 285% more Vitamin C than watermelon - watermelon has 8.1mg of Vitamin C per 100 grams and grapefruit has 31.2mg of Vitamin C.

Vitamin A

Grapefruit has 107% more Vitamin A than watermelon - watermelon has 28ug of Vitamin A per 100 grams and grapefruit has 58ug of Vitamin A.

Vitamin E

Watermelon and grapefruit contain similar amounts of Vitamin E - watermelon has 0.05mg of Vitamin E per 100 grams and grapefruit has 0.13mg of Vitamin E.

Vitamin K

Watermelon and grapefruit contain similar amounts of Vitamin K - watermelon has 0.1ug of Vitamin K per 100 grams and grapefruit does not contain significant amounts.

The B Vitamins

Grapefruit has more folate. Both grapefruit and watermelon contain significant amounts of thiamin, riboflavin, niacin, pantothenic acid and Vitamin B6.

Grapefruit Watermelon
Thiamin 0.043 MG 0.033 MG
Riboflavin 0.031 MG 0.021 MG
Niacin 0.204 MG 0.178 MG
Pantothenic acid 0.262 MG 0.221 MG
Vitamin B6 0.053 MG 0.045 MG
Folate 13 UG 3 UG

Minerals

calcium

Grapefruit has 214% more calcium than watermelon - watermelon has 7mg of calcium per 100 grams and grapefruit has 22mg of calcium.

iron

Watermelon and grapefruit contain similar amounts of iron - watermelon has 0.24mg of iron per 100 grams and grapefruit has 0.08mg of iron.

potassium

Watermelon and grapefruit contain similar amounts of potassium - watermelon has 112mg of potassium per 100 grams and grapefruit has 135mg of potassium.

Antioxidants and Phytonutrients

flavonoids

Naturally occuring in fruits and vegetables, flavonoids are associated with many health benefits and used in a variety of medicinal and pharmaceutical applications. [2][3]

For specific flavonoid compounds, watermelon has more kaempferol than grapefruit per 100 grams, however, grapefruit contains more quercetin than watermelon per 100 grams. Both grapefruit and watermelon contain significant amounts of luteolin.

Grapefruit Watermelon
luteolin 0.6 mg 0.46 mg
kaempferol 0.01 mg 0.45 mg
myricetin 0.01 mg ~
Quercetin 0.33 mg ~

carotenoids

Carotenoids are micronutrients commonly found in plants and some animal products. An example is beta-carotene, the notable carotenoid which is a popular source of Vitamin A.[4][5]

For specific types of carotenoids, grapefruit has more beta-carotene than watermelon per 100 grams, however, watermelon contains more lycopene than grapefruit per 100 grams. Both grapefruit and watermelon contain small amounts of lutein + zeaxanthin.

Grapefruit Watermelon
beta-carotene 686 UG 303 UG
alpha-carotene 3 UG ~
lycopene 1419 UG 4532 UG
lutein + zeaxanthin 5 UG 8 UG

Omega-3 and Omega-6

omega 6s

Comparing omega-6 fatty acids, both grapefruit and watermelon contain small amounts of linoleic acid.

Grapefruit Watermelon
linoleic acid 0.029 G 0.05 G
Total 0.029 G 0.05 G



Customize your serving size


The comparison below is by common portions, e.g. cups, packages. You can also see a more concrete comparison by weight at equal weight (by grams) comparison.

Note: The specific food items compared are: Grapefruit (Grapefruit, raw, pink and red, all areas) and Watermelon (Watermelon, raw) .

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FAQ

Does watermelon or grapefruit contain more calories in 100 grams?
Watermelon and grapefruit contain similar amounts of calories - watermelon has 30 calories in 100g and grapefruit has 42 calories.

Does watermelon or grapefruit have more carbohydrates?
By weight, watermelon and grapefruit contain similar amounts of carbs - watermelon has 7.6g of carbs for 100g and grapefruit has 10.7g of carbohydrates.