 There are numerous factors known to determine the relative rate of lipid metabolism at rest between and within individuals, including: biological sex, endogenous carbohydrate availability, training status and, in particular, feeding. Recent focus has been placed on the potential of alternative nutrients, nutritional supplements and pharmacological agents to modify substrate selection in favour of greater lipid oxidation e.g. caffeine, carnitine, green tea andor to alter lipid absorption e.g. caffeine, carnitine, orlistat, green tea preparations. 