People engaging in diet programmes often strive to incorporate foods that they find tasty without sacrificing essential nutrients or increasing levels of fat, calories, sugar or carbohydrates. For some people, the bitter flavour of a grapefruit’s pink flesh is too intense to endure regularly, and the sweeter orange appeals as a much tastier alternative. Unfortunately, the dietary impacts of these two fruits are different, with grapefruits tending to be the healthier option.
Whiles oranges and grapefruits are both citrus fruits, the latter has often had a more prominent place amongst diet regimens. As Diet.com mentions, these regimens range from the fad grapefruit diets of the 1930s, wherein dieters would consume grapefruits for every meal, to more modern incarnations, in which dieters eat grapefruit daily as a supplement to a healthy, balanced diet.
A 2006 study published in the Journal of Medicinal Food shows that consuming half of a fresh grapefruit, drinking grapefruit juice, or taking the equivalent amount in a grapefruit supplement three times a day can help promote weight loss. The study followed 91 subjects for 12 weeks, some who consumed supplemental grapefruit in the forms described above, and some who consumed supplemental apple juice. Otherwise, all 91 subjects maintained their usual diets. While the subjects consuming the apple juice lost on average approximately 300 g (0.66 lbs.), all of the subjects with some type of grapefruit intake lost at least 800 g (1.76 lbs.) or more. As of 2010, no studies show that oranges can provide these same weight-loss results as grapefruit.
The precise reason why grapefruit was able to produce the weight-loss results shown in the 2006 study is unclear. However, it may be logical to assume that oranges posses the same weight-loss-inducing qualities, making them a worthy substitute in a diet. This is because, as Purdue University points out, the grapefruit, which arose accidentally in the West Indies, is a hybrid between the pomelo and the orange.
According to the fruit resource Poinsettia Groves, oranges and grapefruits both have 0 grams of fat, 0 grams of sodium and 1 gram of protein. However, while 154 grams of grapefruit have 60 calories, 16 grams of carbohydrates and 10 grams of sugar; 154 grams of orange have 70 calories, 21 grams of carbohydrates and 14 grams of sugar. In order for the body to burn fat and lose weight, it must create an energy deficit by exerting more energy than it consumes in calories. The greater amounts of sugar, carbohydrates and overall calories in oranges make eating them a less-efficient food choice in comparison to grapefruit.
The juices from oranges and grapefruits can interact with certain medications. As the Daily Mail Online notes, these include some antibiotics, hay-fever pills and drugs for treating high blood pressure, heart conditions and cancer.