“Assam” means “sour.” Assam Gelugur (variously spelled) is a Southeast Asian name for a family of very sour fruits used for flavoring, in cooking, preserving and as herbal medicine. One local use is for weight loss. In Thailand and throughout the Malay Peninsula, the primary species is Garcinia atroviridis. Related species used for much the same purposes are G. cambogia and G. indica. The active constituent in the fruit is its acid, which has the formidable chemical name 1,2-dihydroxypropane-1,2,3-tricarboxylic acid.
As is true of many herbal products, the benefits of Assam Gelugur extracts are highly dependent upon how they are prepared. The acid must be stabilized generally by the addition of high pH ions (basic or alkali), such as those of potassium, magnesium or calcium — using the wrong stabilizer results in little or no activity. Employing only potassium as the cation, if the material is properly reacted, results in a liquid, not a powder, hence leads to a product that is commercially unusable. In the case of the acid derived from Assam Gelugur, adding any calcium at all reduces some desired benefits and blocks other benefits entirely.
Continue reading here.