Momordica charantia is a thermophilic voluble plant from the tropical and subtropical regions of Asia, Africa and the Caribbean. In central Europe, momordica requires greenhouse plantations. Mature fruits resemble a cucumber or a pumpkin and can be used as other similar vegetables. Crude fruits are very bitter and refreshing. For centuries the plant has been known in Chinese traditional medicine for its antidiabetic effects as well as for the treatment of cancer or infections caused by worms, viruses and malaria. Antidiabetic effects are attributed namely to cucurbitane type triterpenoids, charantin, p-insulin and 9cis-11trans-13trans-conjugated linolenic acid. These substances in momordica preparations show antidiabetic effectiveness in clinical studies by increasing insulin secretion and deceasing insulin resistance or glucose absorption from the gut. Beside this main effect the extract possesses certain neuroprotective and antioxidant effects (especially p9cis-11trans-13trans-conjugated linolenic acid) and contributes to normalize blood lipid and adipokine levels which results in the normalization of metabolic syndrome. Antidiabetic effectiveness of momordica was compared to active treatment with several oral antidiabetic drugs and proved comparable effects. However, the number of studies is limited and their methodological approach variable. Therefore, the evidence is so far inconclusive.