Lychees are mainly composed of water and carbs — which make up 82% and 16.5% of the fruit, respectively (1Trusted Source).

A 3.5-ounce (100-gram) serving of fresh lychees provides the following nutrients. The table below shows the main nutrients in fresh lychees (1Trusted Source):

• Calories: 66
• Protein: 0.8 grams
• Carbs: 16.5 grams
• Sugar: 15.2 grams
• Fiber: 1.3 grams
• Fat: 0.4 grams

Carbs and Fibers

Besides water, lychees are mainly composed of carbs.

A single lychee — either fresh or dried — contains 1.5–1.7 grams of carbs (1Trusted Source).

The majority of the carbs in lychees comes from sugars, which are responsible for their sweet taste. They’re relatively low in fiber.

Vitamins and Minerals

Lychees are a decent source of several vitamins and minerals, including:

• Vitamin C: The most abundant vitamin in lychees. One lychee provides around 9% of the Reference Daily Intake (RDI) for vitamin C (1Trusted Source).
• Copper: Lychees are a decent source of copper. Inadequate copper intake may have adverse effects on heart health (2Trusted Source).
• Potassium: An essential nutrient that may improve heart health when eaten in sufficient amounts (3Trusted Source).

SUMMARY

Lychees are primarily composed of water and carbs, most of which are sugars. Compared to many other fruits, they’re low in fiber. They’re also high in vitamin C and offer decent amounts of copper and potassium.

 

Like other fruits, lychees are a good source of various antioxidant plant compounds.

In fact, they have been reported to contain higher levels of antioxidant polyphenols than several other common fruits (4Trusted Source).

Antioxidants in lychees include:

• Epicatechin: A flavonoid that may improve heart health and reduce your risk of cancer and diabetes (5Trusted Source, 6Trusted Source).
• Rutin: A flavonoid which may help protect against chronic diseases, such as cancer, diabetes, and heart disease (6Trusted Source, 7Trusted Source).

Oligonol

Oligonol is a dietary supplement that is often mentioned in connection to lychees.

It’s a patented mixture of antioxidants (proanthocyanidins) derived from lychee skin and green tea, developed by the Amino Up Chemical Corporation in Japan.

The antioxidants are chemically altered to increase their uptake from your gut (8Trusted Source).

Several studies indicate that Oligonol may reduce abdominal fat, fatigue, and inflammation after exercise (9Trusted Source, 10, 11Trusted Source, 12Trusted Source).

However, as it’s not found naturally in lychee fruits, its health effects don’t apply to lychees.

SUMMARY

Like most fruits and vegetables, lychees are a good source of antioxidants and other healthy plant compounds. These include epicatechin and rutin. Fresh lychees don’t contain any Oligonol, as is often claimed.

 

The health effects of lychees have not been studied yet.

However, including a variety of fruits and vegetables in your diet may improve your health and reduce your risk of several chronic diseases (13Trusted Source, 14Trusted Source, 15Trusted Source).

Lychees contain several healthy minerals, vitamins, and antioxidants, such as potassium, copper, vitamin C, epicatechin, and rutin. These may help protect against heart disease, cancer, and diabetes (3Trusted Source, 6Trusted Source, 7Trusted Source, 16Trusted Source).

Animal studies also indicate that lychee extract may help fight liver cancer (17Trusted Source).

Still, further studies are needed to confirm the health benefits of lychees in humans.

SUMMARY

The health effects of lychees have not been studied directly. However, they contain several nutrients and antioxidants that are important for health.

When eaten in moderation as a part of a healthy diet, lychees do not have any known adverse health effects.

However, lychees have been associated with brain inflammation in South and Southeast Asia.

Whether lychees are responsible is not entirely clear, but scientists have hypothesized that the toxin hypoglycin A may be responsible. Further studies are needed (18Trusted Source, 19Trusted Source).

Additionally, lychees may cause an allergic reaction in rare cases (18Trusted Source).

SUMMARY

Though lychees have been associated with brain inflammation in parts of Asia, it’s uncertain that they’re the culprit. Eating lychees in moderation should be safe for most people.

 

Lychees are popular in Southeast Asia and China but less common in other countries.

They have a sweet and flowery flavor and are a good source of vitamin C and several beneficial antioxidants. This makes them an excellent addition to a healthy diet.