Carambola, also known as Star fruit, is the fruit of the Averrhoa carambola tree. It is native to Indonesia, India and Sri Lanka, and is very popular throughout Southeast Asia, Malaysia and parts of East Asia. It is also grown in Hawaii, Brazil, Florida and the Caribbean. Malaysia is the largest exporter of carambola, providing Europe and Asia with the fruit.
The small, unripe fruits are green, ripening to yellow with a waxy skin. When cut horizontally, a star is formed, which is why it is often called Star fruit. The entire fruit is edible, best when ripe. It can be juicy and has its own distinct flavor, but is sometimes compared to orange, grapefruit or papaya, or a mix of all three. It is often included in fruit salads.
Carambola is considered a “super fruit,” as it is very high in antioxidants and vitamin C, and low in sugar and sodium. However, like grapefruit, carambola contains oxalic acid and, therefore, should not be consumed by anyone with kidney problems. Also, like grapefruit, carambola is not advised for anyone taking statins or other drugs that have interactive issues with grapefruit.
In Malaysia, locals use carambola to reduce blood sugar and to prevent high blood pressure. They boil three to four ripe fruits with some water and reduce it to about one cup, then drink it warm every morning and evening.