How Many Calories In Grapefruit?

Grapefruits grow to be three different sizes -- small, medium and large -- and although the calorie content of each size grapefruit is slightly different, no matter what the size, one whole grapefruit contains few calories.

One whole small grapefruit has 64 calories. A whole medium grapefruit contains 82 calories. The number of calories in a whole large grapefruit totals 106. Contrary to popular belief, eating a grapefruit does not help eliminate fat.

The skin on one whole grapefruit can be thick or thin. If the skin is thick, the grapefruit may appear large, but once the grapefruit is peeled and the skin is discarded, it will be smaller than its original size, and the calorie content may be less than what you first expected it to be.

Although grapefruit is a low-calorie, healthy fruit, it can cause dangerous side effects, including heart arrhythmia or even death, when mixed with certain drugs. If you are taking any medication, consult your doctor before consuming grapefruit or grapefruit juice.

How Many Calories Do Ruby Red Grapefruits Have?

Ruby red grapefruit make a delicious, healthy snack or addition to any meal. In addition to the tasty flavor, ruby red grapefruit are a good source of vitamin C. Vitamin C protects against damage caused by free radicals.

Each ruby red grapefruit contains two servings. One serving of grapefruit contains 52 calories. Two of those calories are from fat. Three percent of those calories are from fat, 91 percent are from carbohydrates and 6 percent are from protein.

One serving of ruby red grapefruit provides you with 28 percent of the daily recommended value of vitamin A and 64 percent of vitamin C. In addition, each serving contains 3 percent of the daily value of calcium and 1 percent of iron.

Ruby red grapefruit contain 166 mg of potassium per serving and 8.47 g of sugars. Additionally, there is 0.95 g of protein and no cholesterol in each serving.

Calories In One Cup Of Grapefruit

One cup or 8.1 oz of fresh grapefruit contains 74 calories. The majority of the fruit's calories are derived from carbohydrates.

One cup of fresh grapefruit does not provide significant sources of dietary fat or protein. One cup of grapefruit only contains 0.2 g of fat and 1.4 g of protein. The same size grapefruit provides 18.6 g of carbohydrates and 16.1 g of sugars.

Grapefruit provides traces of various vitamins, minerals and antioxidants. One cup provides 79.1 mg of vitamin C and 2132 IU of vitamin A. Grapefruit also provides traces of water-soluble B vitamins such as thiamin, riboflavin, niacin, pantothenic acid, B-6 and folate. One cup of the fruit also contains 28 mg of calcium, 320 mg of potassium, 18 mg of magnesium, and traces of iron, zinc, copper and selenium. One cup also contains antioxidants such as 2,610 mcg of lycopene and 14 mcg of lutein.

The Nutritional Guide To Grapefruit Juice

There are different varieties of grapefruit juice, just as there are of the fruit itself. Red, pink or white grapefruit can be fresh squeezed for a healthy treat that is low in calories but high in nutrition. The USDA National Nutrient Database reports that grapefruit juice, white or red, contains only 96 calories along with a host of other nutritional benefits.

Red and white grapefruit both contain high vitamin content. The only difference between the two types of grapefruit lies in their vitamin A content. While a 1 cup serving of white grapefruit juice only contains 24.7 IU of vitamin A, the same serving of red grapefruit juice contains 1087 IU of vitamin A, which is more than 20 percent of the recommended daily intake according to the Institute of Medicine. Vitamin A is necessary for healthy skin tissue, teeth, mucous membranes and eyesight according to the National Institutes of Health. It is also a powerful antioxidant vitamin, which means it helps cells fight off free radical damage that can alter DNA and lead to disease and cancer.

Vitamin C is another antioxidant vitamin found in equal amounts in pink and white grapefruit, with a whopping 93.9 mg which is more than 150 percent of the RDI. The B vitamin family finishes out grapefruit's vitamin content, with the exception of B-12, which is found primarily in animal food sources.

Grapefruit contains several essential minerals, with potassium being the highest in content. A 1 cup serving of grapefruit juice, red or white, contains 400 mg of potassium, which is more than 10 percent of the RDI. The University of Maryland Medical Center reports that potassium plays a major role in muscle contraction that makes it very important to heart function. It also reduces blood pressure, your risk of stroke and helps maintain bone health. Other minerals in grapefruit juice include magnesium, phosphorous, iron, calcium, copper, sodium and zinc. The USDA reports that red and white grapefruit juice also contain 1.2 g of protein, or 2 percent of the RDI.

Grapefruit juice offers nutritional benefits that you won't find listed on a data sheet. Grapefruit lowers cholesterol and triglyceride levels. Researchers report that this is particularly true of red grapefruit, as it has a higher antioxidant content than white grapefruit. Grapefruit juice can also lower blood sugar levels and improve insulin resistance.