The second lesson we should heed from these studies is that when various nutrient supplements are taken in combination, they may yield difficult-to-predict synergistic actions, the mechanics of which may not yet be understood. Specific nutrients, in this case quercetin, may prove to be more effective when taken with other specific nutrients.
Third, we should consider using quercetin in combination with EGCG and fish oil concentrates as a routine protocol. In clinical practice this is often done unintentionally; we encourage people to drink green tea instead of coffee and we suggest they eat fish or take fish oil on general principle. The enhanced absorption of quercetin resulting from combining it with green tea may work 2 ways. A January 2010 study reports red onion, an excellent source of quercetin, enhances absorption of EGCG from green tea.
The chemical form of quercetin may also play a significant role. Though foods contain very low levels of quercetin, the structure is slightly different than that found in nutritional supplements, and we cannot rule out that absorption of quer