Calories in Longan: Nutritional facts for Longan Types

A 100g serving of raw longan flesh contains 60 calories. A 100g serving of dried longan meat provides 286 calories.

One kilogram (1000g) of raw longan flesh contains 600 calories. One kilogram (1000g) of dried longan meat provides 2,860 calories.

A single fresh longan fruit (3.2g flesh) contains 2 calories. Commercial packaged options vary, as a serving of Aroy-D Longan in Syrup (140g or 0.5 cup) contains 110 calories, while a serving of Dragonfly Dried Longan (30g or 1oz) provides 84 calories. A serving of Roland Canned Longan (140g) has 100 calories.

The nutritional profile of longan offers distinct advantages derived from the concentration of polyphenols and Vitamin C in the fruit. The primary health benefits are detailed below.

• Boosts Immune Defense: The fruit serves as an exceptional source of Vitamin C, providing nearly 100% of the Daily Value in a 100g serving. A review by Carr, A. C., & Maggini, S. (2017), "Vitamin C and Immune Function," confirms that high Vitamin C intake supports the production and function of leukocytes, which are critical for fighting infections.
• Supports Cognitive Function: Longan contains bioactive compounds that may protect brain health. A study by Park, S. J., et al. (2010), "The memory-enhancing effects of Eucommia ulmoides Oliver and Dimocarpus longan Lour. in mice," suggests that extracts from the fruit can improve memory and learning performance by protecting neurons from oxidative stress.
• Provides Antioxidant Protection: The fruit contains ellagic acid and gallic acid, which neutralize harmful free radicals. A study by Soong, Y. Y., & Barlow, P. J. (2004), "Antioxidant activity and phenolic content of selected fruit seeds," highlights that longan seeds and pulp possess significant antioxidant capacity that supports cellular health.

The consumption of longan presents specific health risks related to sugar concentration and traditional medicine concepts. These potential drawbacks are outlined here.

• High Sugar Content: Longan contains a high concentration of simple sugars like sucrose and fructose, which can cause rapid spikes in blood glucose. A study by Atkinson, F. S., et al. (2008), "International tables of glycemic index and glycemic load values: 2008," classifies tropical fruits with high sugar density as foods that require strict portion control for individuals with insulin resistance. A healthier alternative for diabetics is berries. A suggested amount is to limit consumption to 10-15 fruits per day.
• Internal Heat (Traditional Medicine): In Traditional Chinese Medicine (TCM), excessive consumption of longan is believed to cause "internal heat," leading to symptoms like sore throat or nosebleeds. A review by Yin, J., et al. (2008), "Traditional Chinese Medicine in the Treatment of Metabolic Syndrome," notes that "warm" foods like longan should be balanced with "cooling" foods to maintain physiological equilibrium.

Longan affects digestion positively by providing dietary fiber and water, which aid in bowel regularity, but excessive consumption can upset the stomach due to fructose load. The fruit provides 1.1g of fiber per 100g serving, which adds bulk to the stool. A study by Slavin, J. L. (2013), "Fiber and prebiotics: mechanisms and health benefits," confirms that fiber intake reduces transit time and prevents constipation. The high fructose content can cause issues for some individuals. A study by Gibson, P. R., et al. (2007), "Fructose malabsorption and the bigger picture," identifies excess fructose as a trigger for bloating and gas in people with malabsorption syndromes.

Yes, longans are good for health because the fruit provides a dense source of Vitamin C, potassium, and antioxidants that support immune and cardiovascular function. The fruit's impact on immune health is positive due to the high ascorbic acid content. A study by Wintergerst, E. S., et al. (2006), "Immune-enhancing role of vitamin C and zinc and effect on clinical conditions," notes that Vitamin C reduces the duration and severity of respiratory infections. Regarding cardiovascular health, the potassium content helps regulate blood pressure. A study by Aburto, N. J., et al. (2013), "Effect of increased potassium intake on cardiovascular risk factors and disease," found that potassium intake lowers the risk of stroke. For cellular protection, the polyphenols offer anti-inflammatory benefits. A study by Rangkadilok, N., et al. (2007), "Evaluation of free radical scavenging and antityrosinase activities of standardized longan fruit extract," demonstrates the potent antioxidant activity of the fruit.

The moisture content and sugar concentration determine the calorie count of a longan variety. Dried longan has the highest calorie value at 286 calories per 100 grams, a consequence of the dehydration process concentrating the natural sugars. Fresh Biew Kiew longan contains a slightly higher calorie value at 62 calories per 100 grams, representing a version with a higher brix (sugar) level. Standard fresh varieties like Kohala and Sri Chompoo contain the lowest calorie value at 60 calories per 100 grams, representing the baseline for the hydrated fruit.

Yes, longan loses heat-sensitive nutrients, particularly Vitamin C, during cooking processes like boiling or canning. A study by Effect of thermal treatment and storage on the stability of organic acids and the functional value of grapefruit juice," (applied to fruit processing) confirms that thermal processing degrades ascorbic acid significantly. Dried longan retains minerals and fiber. A study by Qian, L., et al. (2021), " Effect of drying methods on the texture properties and active ingredients in Longan flesh," found that while Vitamin C is lost, the concentration of polyphenols and antioxidant activity can remain stable or even increase relative to weight in dried forms.

The lineage of longan traces back to the mountain ranges between Southern China and Burma (Myanmar). The tree, Dimocarpus longan, has been cultivated in China for over 2,000 years, dating back to the Han Dynasty. The name "longan" comes from the Cantonese lùhng-ngáahn, meaning "dragon eye," describing the fruit's appearance when shelled—a translucent white flesh with a dark seed resembling a pupil. Migration and trade routes spread the fruit to Thailand, Vietnam, and eventually to Hawaii and Florida in the 20th century.