Effectiveness of Traditional Malaysian Vegetables (ulam) in Modulating Blood Glucose Levels

• Published in: Asia Pacific Journal of Clinical Nutrition Vol. 23; no. 3; pp. 369 - 376
• Main Authors: Bachok, Mohd Faez, Yusof, Barakatun-Nisak Mohd, Ismail, Amin, Hamid, Azizah Abdul
• Format: Journal Article
• Language: English
• Published: Australia HEC Press 01.01.2014
• Subjects: Analysis; Blood Glucose - drug effects; Blood sugar; Centella; Clinical trials; Diabetes; Glucose; Humans; Malaysia; Medicinal plants; Methodology; Momordica charantia; Observational studies; Plant Extracts - pharmacology; Plants, Medicinal; Treatment; Triterpenes - pharmacology; Vegetables; Malaysia; India; Medicinal plants; Complementary therapy; Blood Glucose; Clinical trial; Diabetes mellitus
• ISSN: 0964-7058; 1440-6047
• DOI: 10.6133/apjcn.2014.23.3.01

'Ulam' refers to a group of traditional Malaysian plants commonly consumed as a part of a meal, either in the raw form or after a short blanching process. Many types of 'ulam' are thought to possess blood glucose-lowering properties, but relatively little is known on the effectiveness of 'ulam' in modulating blood glucose levels in humans. This review aims to systematically evaluate the effectiveness of 'ulam' in modulating blood glucose levels in humans. A literature review was conducted using multiple databases with no time restriction. Eleven studies were retrieved based on a 'priori' inclusion and exclusion criteria. In these 11 studies, only 'Momordica charantia', locally known as "peria katak", was extensively studied, followed by 'Centella asiatica', locally known as "daun pegaga", and 'Alternanthera sessilis', locally known as "kermak putih". Of the 11 studies, 9 evaluated the effectiveness of 'M. charantia' on blood glucose parameters, and 7 of which showed significant improvement in at least one parameter of blood glucose concentration. The remaining 2 studies reported nonsignificant improvements in blood glucose parameters, despite having high-quality study design according to Jadad scale. None of the studies related to 'C. asiatica' and 'A. sessilis' showed significant improvement in blood glucose-related parameters. Current clinical evidence does not support the popular claim that 'ulam' has glucose-lowering effects, not even for 'M. charantia'. Hence, further clinical investigation is needed to verify the glucose modulation effect of 'M. charantia', 'C. asiatica', and 'A. sessilis'.