Calories in Carambola: Nutritional facts for Carambola Types

One hundred grams (3.5 oz) of raw carambola, or star fruit, contains 31 calories.

One kilogram (2.2 lbs) of raw carambola contains 310 calories.

The calorie of one raw carambola fruit ranges from 19 to 38 calories, depending on its size. A small carambola (61 g) contains 19 calories, while a large carambola (124 g) contains 38 calories.

Carambola provides some health benefits like supporting immune function and promoting digestive health due to its high content of Vitamin C and dietary fiber. Carambola (Averrhoa carambola), also known as star fruit, is a tropical fruit with a distinctive star shape when sliced. A list of the health benefits of carambola are shown below.

• Excellent Source of Vitamin C: Star fruit is packed with Vitamin C, a powerful antioxidant that boosts the immune system, protects cells from free radical damage, and is essential for collagen synthesis for healthy skin (Carr AC, Maggini S., 2017, "Vitamin C and Immune Function").
• Good Source of Dietary Fiber: It contains a good amount of both soluble and insoluble fiber, which aids digestion, helps prevent constipation, promotes regular bowel movements, and can contribute to feelings of fullness.
• Rich in Antioxidants: Carambola contains various plant-based antioxidants, including flavonoids like quercetin, epicatechin, and gallic acid. These compounds help combat oxidative stress and may reduce inflammation.
• Low in Calories: Star fruit is very low in calories, making it a healthy choice for a snack or addition to meals, especially for those managing their weight.
• May Support Heart Health: The combination of fiber (which can help lower cholesterol), potassium (which helps regulate blood pressure), and antioxidants in carambola contributes to overall cardiovascular health.
• Promotes Hydration: With its high water content, carambola is a hydrating fruit that helps contribute to daily fluid intake.
• Contains B Vitamins: Carambola is a source of B vitamins, particularly Pantothenic Acid (Vitamin B5) and folate, which are important for energy metabolism and cell function.
• Provides Copper: It is a good source of the mineral copper, which is essential for iron absorption, red blood cell formation, and maintaining healthy nerves and blood vessels.

Carambola has been known to cause some unwanted effects like kidney damage in susceptible individuals and potential medication interactions due to its high content of oxalates and a specific neurotoxin. A list of the downsides of carambola are shown below.

• High Oxalate Content and Kidney Issues: Carambola contains a high amount of oxalic acid. In healthy individuals, this is not an issue, but for people with pre-existing kidney disease or impaired kidney function, consuming star fruit can lead to oxalate nephropathy and acute kidney injury (Neto MM, et al., 2003, "Intoxication by star fruit (Averrhoa carambola) in 32 uraemic patients: treatment and outcome").
• Contains a Neurotoxin (Caramboxin): Star fruit contains a neurotoxin called caramboxin. Healthy kidneys can filter this toxin out without any problems. However, in individuals with kidney failure, this toxin can build up in the body and cause severe neurological symptoms, including hiccups, confusion, seizures, and even death (Garcia-Cairasco N, et al., 2013, "Star-fruit-induced neurotoxicity: a review of the literature").
• May Interact with Medications: Like grapefruit, star fruit can interfere with the metabolism of certain medications by inhibiting the CYP3A4 enzyme in the gut and liver. This can lead to higher, potentially toxic levels of some drugs in the bloodstream. Individuals taking prescription medications should consult their doctor before consuming star fruit.

No, the majority of the carbohydrates in carambolas are not complex carbohydrates, they are simple carbohydrates (sugars) and dietary fiber. While carambola contains some complex carbs, its carbohydrate profile (6.7g per 100g) is primarily composed of natural sugars (4.0g) and dietary fiber (2.8g), rather than large amounts of starch. Complex carbohydrates are long chains of sugar molecules found in starchy vegetables and whole grains. They are broken down more slowly, providing sustained energy and helping to stabilize blood sugar levels. The benefits of complex carbohydrates, particularly from whole grains, are linked to reduced risks of chronic diseases (Aune D, et al., 2016, "Whole grain consumption and risk of cardiovascular disease, cancer, and all cause and cause specific mortality..."). 

Yes, for healthy individuals with normal kidney function, carambola is a good and nutritious fruit. It is low in calories, high in water content, and provides an excellent source of Vitamin C and a good amount of dietary fiber. It also offers beneficial antioxidants and minerals like copper. A review of the fruit by Shui G and Leong LP (2006), "Residue from star fruit as a valuable source for functional food ingredients and antioxidant nutraceuticals," highlights its potent antioxidant capacity. There is no specific suggested consumption rate, but for healthy people, including star fruit as part of a varied fruit intake is a good choice. However, due to the risks of oxalate and caramboxin toxicity, it is strongly advised that individuals with any form of kidney disease or impaired kidney function completely avoid consuming star fruit.

Yes, carambolas are very suitable for weight-loss diets. They are a low-calorie, high-fiber, and high-water-content fruit. One medium star fruit (91 g) contains only 28 calories, making it a light and refreshing snack. The high fiber content (2.5 g per medium fruit) helps to promote satiety, the feeling of fullness, which can help reduce overall calorie intake and prevent overeating. Foods with low energy density and high fiber are consistently recommended for weight management.

The calories in carambola, or star fruit, show no significant change between the common types. Both the larger, sweet carambola varieties and the smaller, tart carambola varieties contain an identical low calorie count of 31 calories per 100g. The primary difference between these types is their flavor profile, determined by their sugar-to-acid ratio, not their overall energy content. The only way calories would change significantly is through preparation; for example, making a jam or a sweetened juice from carambola would dramatically increase the calorie count due to the addition of sugar.

The origin of the carambola, or star fruit, is believed to be Southeast Asia, with its native range likely including Sri Lanka, Indonesia, and the Moluccas (the Spice Islands). It has been cultivated in the region for centuries. The fruit was spread by traders and explorers to India, China, and eventually to other tropical and subtropical parts of the world, including the Americas (particularly Florida and the Caribbean) and Australia. The name "carambola" is derived from a Sanskrit word.