Research has shown that Sida cordifolia leaves contain small quantities of both ephedrine and pseudoephidrine (Ghosal et al., 1975). However, the quantities are low, with less than 2% of ephedrine and pseudoephedrine found in the leaves of Sida cordifolia. Ephedrine is known to stimulate the central nervous system (CNS), and as such can enhance weight loss. Traditionally nutrition companies used plants such as Ma-Huang (Ephedra plant), because it contained relatively large amounts of ephedrine, in their weight loss products. However, since this product was banned in many countries including the USA and UK, they are now looking for alternatives. Sida cordifolia, with its ephedrine and pseudoephedrine has gained a lot of interest and is now sold by many of these companies. Some of these companies promote Sida cordifolia as a weight loss supplement by claiming that it stimulates the CNS.
Unfortunately, there is no research in human or animal studies, to support Sida cordifolia's use as a CNS stimulator. In fact, research shows that rather than being a stimulant, Sida cordifolia actually acts as a depressant and decreases CNS activity (Franco et al., 2005). The mice used in this study showed a decreased response to touch as well as a reduction in nerve activity. Additional research appears to confirm that Sida cordifolia does not stimulate the CNS (Medeiros et al., 2005). In this study the oral consumption of Sida cordifolia by rats actually caused a decrease in both heart rate and blood pressure. If it was having a stimulatory effect we would see both heart rate and blood pressure increase. Since Sida cordifolia fails to increase CNS activity, as claimed by some companies, it cannot promote fat loss through CNS stimulation.