3.2 Differences in Response Doses
There is mismatch between administration of doses and levels of phytochemicals / chemopreventive agents in circulating tissue in animal vs. human. Doses delivered to animals/kg of their body weight are especially high in contrast with doses given to human in clinical trials.
For example Curcuminoid’s at high doses [around 6 g/day fractionate into 3 doses] for 12 days was found to be more effective in arbitrary placebo controlled study while lower doses [2g/day of turmeric extract, fractionate in 2 doses] for 7 weeks were found to be ineffective in HNC (Chainani-Wu et al. , 2012). This pharmacokinetic profile is peculiar to the dose range tested in the experimental species (strain of animal used). The known interspecies differences and metabolic differences between species must be accommodated. For integrated pharmacokinetic, studies allometric scaling between species is needed for accurate detailed differences in plasma protein binding and metabolic stability.