You’re right, and normally I wouldn’t put much stock into a study with so few participants and so many potential confounding variables, but the fact of the matter is, it just makes sense to me. Transdermally, there are a number of factors that could make an ingredient in a skin care formulation less potent or effective, including its processing, packaging method, incorrect pH with the other ingredients, and permissibility through the stratum corneum. However, when you ingest a beneficial ingredient, there’s not much to stop proper absorption, unless you’re eating them with a huge amount of other foods or have colitis or something like that. Bottom line: I cite this study because it supports what I’ve always secretly thought, but you’re right – I should find better support.

Also, I don’t have the study to read but did they control the diets of the participants over the 12 week period? With such a small number it seems quite possible that there were significant dietary differences which could impact the results.