Interviewer: Doctor, can you explain what fisetin is?
Dr. Puya Yazdi: Fisetin is a flavanoid. These flavanoids became very popular over the years. While there's been about 50 years of work done on them, they've become very popular lately because they're considered unbelievable antioxidants. What makes something an antioxidant is that, I guess, more and more people are starting to learn about reactive oxidant species and these types of things, but on a cellular level, there's always an interplay between energy and the side effects of energy that are really bad for you. What happens is as your body converts oxygen and sugar into actual usable energy--that usable energy is ATP. The more of this you get produced, a side effect of this is you get these things called reactive oxidant species. These things are extremely bad because they cause damage to other molecules and proteins inside of cells. Eventually, what happens is you accumulate more and more of these over time; they cause greater and greater amounts of damage in your cells, which actually causes cellular death. Once you start causing cellular death, you're then starting to get into tissues, where now you're causing tissue damage. It's thought of as, perhaps, the central mechanism that causes and age and almost all of the effects that occur with aging, whether they be cognitive or skin-related, really are thought of as a major player being this accumulation of this reactive oxidant species. Fisetin, as a flavanoid, is one of the best antioxidants to fight this process during the aging process. Additionally, it has some other mechanisms that are important in cognition that make it a unique flavanoid compared to other flavanoids.
Interviewer: Can you talk about where it's found? Are there other food sources?
Dr. Yazdi: The best food source for fisetin is strawberries.
Dr. Yazdi: So whenever you hear on TV that strawberries are usually found to be good for certain conditions, whether they be cognitive conditions or whether they be heart-related conditions, most likely what makes the strawberries unique is, of all the things that you eat, they have one of the highest sources of fisetin. Now, fisetin is also found in a lot of tree barks and roots and things like that; things you can't eat but things that, if you get that out of there, suddenly it becomes a great supplement. That's what makes fisetin unique is that it's found in a lot of tree barks and things like that that animals can eat but that humans don't have the digestive system to eat.
Dr. Yazdi: But if you were to ask me, is there one fruit or one vegetable which kind of tells the whole fisetin story, it's strawberries. Anytime on TV you hear about the health benefits of strawberries, what they're really talking about is the health benefits of fisetin, which is very profound.