The present invention relates to a number of compositions namely a konjac-mannan mixture, a ginseng composition and a composition comprising konjac-mannan and American ginseng. Methods of use are described including their use for reducing blood glucose in non-diabetic and diabetic individuals, as well as reducing postprandial blood glucose in such individuals. Applications in the treatment of hyperlipidemia, high blood pressure, an increase in nitric oxide, syndrome X and cardiovascular disease are also described. Various other applications of the composition and methods are also described.