As with other fruits, oranges are generally considered to be healthy. Oranges contain no fat, are moderately low in calories and contain a number of beneficial nutrients. Oranges may not be ideal for all nutritional plans, and eating oranges may have disadvantages for you. Consult a doctor before altering your nutritional intake.
Lack of Fat
Oranges do not provide any dietary fat. Although this nutrient is high in calories -- each gram of fat provides 9 calories, compared to 4 in a gram of carbohydrates or protein -- it can be healthy. Your body needs dietary fat to absorb certain vitamins, and dietary fat also provides energy for endurance exercise and aids in blood clotting and brain development. Thus, the lack of fat can be detrimental, especially if you use oranges to replace foods such as nuts, which provide healthy fats.
Low in Fiber
If you're dieting, eating fiber can be beneficial, as it provides feelings of satiety. However, oranges are relatively low in fiber, with just 2 g in an 100 g orange. In addition to making you feel full, fiber helps manage your cholesterol and blood sugar levels, and helps promote regular bowel movements. Thus, eating oranges in place of foods higher in fiber can be detrimental for weight loss and general health.
Low in Protein
Eating oranges can be detrimental because they are low in protein. An 100 g orange contains just 1 g of protein, a nutrient your body needs for building and maintaining the integrity of muscles, skin and other bodily tissues. Protein can also aid in weight management. Due to the importance of protein, eating oranges instead of a snack richer in protein can have adverse effects on your health.
High in Sugar
While oranges don't contain any artificial sweeteners, the fruit is still rich in sugar, a simple carbohydrate. Simple carbohydrates provide a shorter duration of energy than complex carbohydrates, and sugar can also promote tooth decay. Additionally, sugar has a high glycemic index, meaning it can have a large effect on your blood sugar levels. According to research published in the June 2011 issue of "The Journal of Nutrition," consuming foods with higher glycemic index ratings can slow weight loss progress.
Low in Amino Acids
Oranges contain minimal levels of amino acids, which help build and repair cells and activate enzymes and hormones. Amino acids can aid in wight loss, muscle gain and sports performance; research published in the February 2009 edition of "The Journal of Nutrition," one amino acid, arginine, can promote increases in lean muscle mass and reductions in body fat.
Low in Minerals
Although oranges provide a range of vitamins, they are low in minerals. Oranges contain virtually no iron, zinc, copper, manganese, selenium or phosphorus.