Oranges: Health Benefits, Risks & Nutrition Facts

Sweet, juicy oranges make a delicious and healthy snack or addition to a meal. A whole orange contains only about 85 calories and has no fat, cholesterol or sodium. And, of course, "oranges are well known for their vitamin C content," said Laura Flores, a San Diego-based nutritionist.

Oranges may boost your immune system and improve your skin; they also aid with heart health, cholesterol levels and other issues. Oranges may additionally help reduce the risk of respiratory diseases, certain cancers, rheumatoid arthritis, ulcers and kidney stones.

Orange juice is also packed with nutrients but does not contain the fiber of a whole orange. Orange pith, the white substance between the peel and the flesh, is high in fiber. Furthermore, it is easy to consume more calories when drinking orange juice than when eating an orange, warns the Centers for Disease Control.

Here are the nutrition facts about oranges from the U.S. Food and Drug Administration, which regulates food labeling through the National Labeling and Education Act:


Health benefits of oranges

Immune system

Most citrus fruits have a good deal of vitamin C, and oranges have high levels even compared to their tangy brethren. Vitamin C protects cells by scavenging and neutralizing free radicals, explains a 2010 article in the medical journal Pharmacognosy Reviews. Free radicals may lead to chronic conditions such as cancer and heart disease. Not only may oranges help reduce the risk of chronic conditions, but they may also boost a person's immunity when dealing with everyday viruses and infections like the common cold.

Skin

Vitamin C also helps keep skin looking beautiful, by helping fight against skin damage caused by the sun and pollution. It is vital to collagen production and may help reduce wrinkles and improve the skin's overall texture, according to the Cleveland Clinic.

Cholesterol

All the fiber in oranges may help lower cholesterol levels, because it picks up excess cholesterol compounds in the gut and pushes them out in the elimination process. A 2010 study published in the journal Nutrition Research found that drinking orange juice for 60 days decreased low-density lipoprotein (LDL cholesterol or "bad cholesterol") in people with high cholesterol.

Heart

Oranges contain vitamin C, fiber, potassium and choline, which are all good for your heart, so the fruits may give your ticker a big boost. Potassium, an electrolyte mineral, is vital for allowing electricity to flow through your body, which keeps your heart beating. Lack of potassium can lead to arrhythmia, an irregular heartbeat. According to one 2012 study, people who consumed 4,069 mg of potassium each day had a 49 percent lower risk of death from heart disease compared with those who consumed only about 1,000mg of potassium per day. According to Flores, "the potassium found in oranges helps to lower blood pressure, protecting against stroke." She noted another heart-related benefit, pointing out that oranges are "high in folate, which is beneficial in lowering levels of homocysteine, a cardiovascular risk factor."

Diabetes

Oranges are high in fiber, which can help lower blood sugar levels in people with type 1 diabetes and improve blood sugar, lipids and insulin levels in people with type 2 diabetes. The American Diabetes Association lists oranges, along with other citrus fruits, as a superfood for people with diabetes.

Digestion and weight loss

Oranges are high in fiber, which aids in digestion by keeping you regular. It is also good for weight loss. "Oranges are a low-fat, nutrient-rich food with a low glycemic index, which make it an ideal food to consume to protect against obesity, which can lead to other diseases such as heart disease, cancer, diabetes, high blood pressure and stroke," Flores told Live Science. The glycemic index is a measure of how food affects a person's blood sugar levels: Foods with a high glycemic index (such as white bread) cause glucose levels to spike quickly after they are eaten, while foods with a low glycemic index (such as vegetables and legumes) cause blood sugar levels to rise more slowly and remain more constant over time.

Vision

Oranges are vitamin A rich. This nutrient contains carotenoid compounds like lutein, beta-carotene and zeaxanthin, which can help prevent age-related macular degeneration, an incurable condition that blurs central vision. Vitamin A also helps your eyes absorb light, and it improves night vision. Furthermore, the American Optometric Association reports that vitamin C can help reduce the risk of cataracts and may slow the progression of macular degeneration.

Cancer

"The vitamin C in oranges is associated with a reduced risk of colon cancer due to preventing DNA mutations from taking place," Flores said. Studies have shown that about 10 to 15 percent of colon cancers have a mutation in a gene called BRAF.

A 2004 study published in the American Journal of Epidemiology showed that consuming bananas, oranges and orange juice in the first two years of life may reduce the risk of childhood leukemia.

Health risks

Oranges are great for you, but you should enjoy them in moderation, Flores warned. "Eating too many oranges has some uncomfortable side effects," she said. "When eaten in excess, the greater fiber content can effect digestion, causing abdominal cramps and could also lead to diarrhea."

Though oranges are relatively low in calories, eating several of the fruits in a day can add up and may lead to weight gain. It is also possible to have too much vitamin C (more than 2,000 mg a day). An excess of this nutrient may lead to diarrhea, nausea, vomiting, heartburn, bloating or cramps, headaches, insomnia, or kidney stones.

"Because they are a high-acid food, [oranges] can contribute to heartburn, especially for those who already suffer [from heartburn] regularly," said Flores. People with gastroesophageal reflux disease (GERD, also called acid reflux disease) may experience heartburn or regurgitation if they eat too many oranges.

People who are taking beta-blockers should be careful not to consume too many oranges. These medicines increase potassium levels and, if mixed with too many potassium-rich foods like oranges and bananas, can lead to an excess of potassium in the body. This is a significant concern for people whose kidneys are not fully functional, as the additional potassium will not be effectively removed from the body.

Orange peels: edible or poisonous?

Orange peels are not poisonous and, as many cooks know, orange zest can pack a big flavor punch. While orange peels are edible, they are not nearly as sweet or juicy as the pulp. They can also be difficult to digest and, unless you're eating an organic orange peel, covered in chemicals.

If you do eat the peel, you'll get a good amount of nutrients. "Orange peel actually has more fiber then the fruit inside contains," Flores said. "It also has flavonoids in it that contain nutritious benefits." Flavonoids are compounds found in many foods. They are known to have antihypertensive and anti-inflammatory effects, which relieve pressures on the heart.

Additionally, orange peels contain vitamins A, C, B6 and B5; calcium; riboflavin; thiamin; niacin; and folate. One way to get some of the nutrients is by eating the inner part of the peel and leaving the tough outer part. "The pith of the orange — the white part between the skin and fruit — can be sour or bitter but actually contains just as much vitamin C as the fruit itself, with a good deal of fiber," Flores said.