Star Fruit: Nutrition and Health Benefits

Medically Reviewed by Jabeen Begum, MD on November 06, 2023
Written by Amy Gopal
4 min read

Star fruit, also known as carambola, is a tropical fruit that looks like a star when you slice it. Unripe star fruit is dark green, but its thin layer of skin turns glossy yellow as it ripens. Carambolas are oval-shaped and are usually 3 to 5 inches long.

It mainly grows in India, Malaysia, Indonesia, and the Philippines, but you can get it all over the world. Star fruit has many health benefits, but it can be dangerous if you have kidney disease. 

Star fruit tree

Star fruit grows on the Averrhoa carambola tree. The trees grow well in sunny and humid climates like those of Southeast Asia, South America, Australia, and certain parts of the U.S. 

Star fruit taste

Ripe star fruit is fleshy, crunchy, and juicy, and has a sweet and slightly tart taste. Smaller star fruits are more tart than the larger fruits. Over-ripe carambolas may have a fermented flavor, or taste sour. 

Star fruit is low in calories has a lot of vitamins and other nutrients, including the following:

  • Fiber
  • Protein
  • Vitamin C
  • Vitamin B5
  • Folate
  • Copper
  • Potassium
  • Magnesium

Anti-inflammatory ability. The high levels of antioxidants in this fruit make it a good anti-inflammatory that can help ease symptoms of psoriasis and dermatitis.

Weight loss promotion. The fiber in star fruit can boost your metabolism and help you feel full longer, so you may eat less. It's also a low-cal snack.

Immunity-boosting ability. Star fruit gives you a healthy dose of vitamin C, which helps your body make germ-fighting white blood cells for a strong immune system.

Improved heart health. The potassium in star fruit helps lower your blood pressure, which lowers your risk of a heart attack or stroke. Research shows it also may lower cholesterol levels.

Improved digestion. The fiber in star fruit helps move waste through your digestive tract, relieving constipation, bloating, cramping, and diarrhea.‌

Eating star fruit is dangerous if you have kidney disease.

Carambolas have many helpful nutrients, but they also contain a substance called caramboxin that is a neurotoxin. That means it can affect your brain and cause problems in your nervous system. Another substance in star fruit, oxalate, can cause damage at high concentrations, leading to reduced kidney function. If your kidneys are healthy, they can process and pass toxins out of your body. But if you have kidney disease, the toxins stay in your body and can cause serious illness.

The symptoms of star fruit poisoning include:

It's even possible to die from it. If you have kidney disease, you should never eat star fruit. 

Star fruit drug interactions

Like certain other fruits, star fruit can change the way some prescription drugs work in your body. Ask your doctor whether star fruit is safe to eat with your medications. Avoid eating star fruit if you take: 

  • Bosutinib
  • Panobinostat
  • Venetoclax

You can find star fruit at local grocery stores, usually year-round. In the U.S., the fruits are harvested twice a year in South Florida: from August to September and December through February. 

Star fruit tastes best when it's ripe. Here are some ways people enjoy star fruit around the world:

Eat star fruit raw, on its own, or with other fruit. Try pairing the fruit with avocados, kiwis, mangoes, and bananas in a fruit salad.

Cook it as part of a main dish. Star fruit is used in many recipes, including Vietnamese sour soup (often with seafood) and Indian curries.

Make a puree, jam, or pickle. You can preserve star fruit so it can be kept in the fridge or freezer to enjoy later. In India, star fruit is used for certain chutneys. 

Create an edible garnish. You can sauté star fruit slices for a second or two, and sprinkle with sugar to glaze. Pair this with fish and poultry dishes, or use it as a substitute for lemon or lime slices to garnish chilled beverages. 

Drink it. Use a juicer to extract star fruit juice, or add chopped star fruit to your blender with other fruit for a smoothie. 

To create "star" slices, do the following:

  1. Clean a ripe star fruit with water, then place it on a cutting board.
  2. Carefully run a sharp knife along each of the five ridges, removing and discarding the brown outer edge. You don't need to peel the rest of the skin. 
  3. Position the star fruit horizontally on the cutting board, then begin cutting crosswise to your desired thickness. 
  4. Remove seeds from each star slice before cooking or serving. 

If you buy a green-ribbed star fruit, let it ripen at room temperature, occasionally turning it, until it turns yellow and its fragrant "perfume" develops. You're looking for a full floral-fruity aroma, which means the fruit is at its best taste.

You can store ripened carambolas at room temperature if you're going to serve them in a day or two. The ripe fruit will last a bit longer in the refrigerator. You'll know star fruit is over-ripe when it gets a lot of brown spots.

Star fruit is a delicious, nutritious fruit that is low in calories but packed with vitamin C, fiber, and antioxidants.

People with kidney problems or those who take prescription drugs should talk with their doctor before eating this fruit.