Orange juice rapidly increases the blood sugar level in diabetics, reports SFGate. It is a recommended carbohydrate for diabetics suffering from hypoglycemia, which is low blood sugar. Ingesting 4 ounces of orange juice raises the blood sugar level within 10 to 15 minutes.
The glycemic index rating of orange juice is between 66 and 76 on a scale of 100, according to SFGate. Several factors can affect the glycemic index rating, including the freshness of the fruit used to produce the juice, if it was made fresh or from concentrate and whether or not it contains pulp.
Fruit and 100 percent fruit juices with no sugar added are considered an important part of a diabetic diet for their nutritional value, including fiber, vitamins, minerals and phytochemicals, according to the American Diabetes Association. Fruits and fruit juices should be consumed with foods high in protein, fat or fiber to slow the rate of carbohydrate absorption, limiting its affects on blood sugar levels, says SFGate.
If a diabetic is sick with a cold or other illness, he should pay close attention to blood sugar levels, according to MedlinePlus. If his blood sugar is below 100 milligrams per deciliter or falling fast and does not rise after eating, orange juice can be used to raise blood sugar levels.