As carbs are digested, they're broken down into glucose (sugar) and shuttled into the bloodstream, thereby raising your blood sugar levels. Because fruits contain carbs, foods like oranges will raise your blood sugar levels.
But that doesn't mean you have to avoid them — in fact, there are no fruits to avoid for diabetes. "When it comes to diabetes, there's no need to avoid fruit," says Erin Palinski-Wade, RD, CDE, author of 2-Day Diabetes Diet. In fact, fruits like oranges are a rich source of nutrients, according to the American Diabetes Association.
While there aren't necessarily best fruits for diabetes, it's safe to add fruit to your diet (and the ADA encourages you to do so). Other low-sugar fruits include raspberries, strawberries and grapefruit, according to the USDA.
What Happens to Your Blood Sugar After Eating an Orange?
The extent to which your blood sugar levels rise after eating an orange will depend on the amount of the fruit you have at one time, the size of the orange, how it's been processed and what other foods you're eating with it. Here's how fresh oranges and orange juice will each affect your blood sugar levels.
Fresh Oranges and Blood Sugar
In general, the majority of your fruit intake should come from whole foods rather than juices, says Palinski-Wade. To understand the extent to which oranges raise your blood sugar levels, you'll need to know how many total carbohydrates are in the fruit.
One raw Florida orange contains about 16 grams of carbs, 9 of which are sugar, according to the USDA. You can subtract the orange's fiber content (about 3 grams) from this total, however, because unlike other types of carbohydrates, fiber does not raise your blood sugar levels. That means the available carbohydrates in an orange totals about 13 grams. (For comparison, a slice of white bread has about 11.5 grams of available carbohydrates.) The larger the orange, the greater the chances it will affect your blood sugar levels.
What About Orange Juice?
"You don't have to avoid orange juice completely, but people with diabetes have to be very cautious about the quantity [of juice they have]," says Palinski-Wade. "Four ounces of orange juice is the equivalent of eating an orange, but it doesn't feel as satisfying as the whole food, which gives you the fiber as well."
Four ounces of canned, unsweetened orange juice has about 13 grams of available carbohydrates, according to the USDA. An orange juice made from concentrate can run about the same, with 14 grams of available carbs. Compare these numbers to the 11.5 grams of carbohydrates found in store-bought white bread and you'll see that a 4-ounce serving of orange juice can raise your blood sugar levels higher than one slice.
Keep in mind if you serve yourself some orange juice in a large glass, you might pour out as many as 8 ounces, which would net you close to 28 grams of available carbs, or more than two slices of bread.
Read more: The Best Nuts for People With Diabetes
How to Control Your Blood Sugar
To prevent your blood sugar levels from rising too high, you might want to stick to one 4-ounce serving of orange juice a day, says Palinski-Wade. If you like to have orange juice in the morning, she recommends cutting a glass of OJ with some water or a club soda or seltzer. "It makes it bubbly and a bit more fun," she says. "You're still getting the same flavor, but a larger volume for the same amount of carbohydrates."
Fresh, whole oranges can be part of a healthy diet to help control diabetes, too. The peeling will slow you down, and the higher fiber content of oranges will increase your satiety levels, helping you feel fuller with fewer carbohydrates and calories.