Is this a review that misses the forest for all the trees The problem with this review visit focuses on all kinds of arcane chemical and terminological issues instead of the research on polyphenols that demonstrates that they are enormously protective biological compounds with a highly pleiotropic physiologic signature I doubt very much that people want to read this much arcane chemistry and certainly not this much hairsplitting about chemical terminology The more important issue is how and why polyphenols are a fundamental component of the human diet and have been for tens of thousands of years if not longer and exactly how they function as protective compounds I don t have enough time unfortunately pitch in on this effort but I m cutting and pasting below a brief overview from a book chapter which I wrote emphasizing the enormously complex and fundamentally protective effects that these compounds have It s troubling that this review doesn t really address any of these issues I wish I had time to pitch in on a major rewrite of this but this is all I can contribute for referencing on this little snippet see Watt DF 2012 The biology of aging implications for understanding the diseases of aging and healthcare in the 21st century Contributed chapter in Textbook of Geriatric Neurology Eds Nair and Sabbagh In press for 2012 Although conventionally regarded as antioxidants polyphenols are an enormous class of substances constituting perhaps as many as 6 000 distinct compounds found in plants principally fruits and vegetables that have enormously pleiotropic effects on human and mammalian physiology Some of these effects may be more biologically significant than any direct free radical scavenging done by a polyphenol they include many effects on cell signaling the regulation of growth factors and apoptosis the regulation of cell cycling the regulation of inflammation the modulation of many if not most cellular stress pathways an impact on multiple transcription factors including those involved in energy homeostasis and consistent with their conventional designation the management of oxidative stress Virgili and Marino 2008 Many of these effects on aspects of cell signaling require much lower levels of polyphenol than any direct free radical scavenging in serum or tissues Indeed from this perspective polyphenols look less like antioxidants and more like complex cell physiology and cell signaling modulators However it seems unlikely that such a designation will replace the catchy title of antioxidant even in the context of increasing evidence that such a title may be fundamentally misleading Many if not most of the phenotypes of aging oxidative stress mitochondrial dysfunction inflammation and declining autophagy among others appear to be partially modulated by various polyphenols From this perspective if our ancestors consumed more plants than we do and did so over tens of thousands of years if not longer the relative removal of polyphenols from the human diet in those eating minimal fruits and vegetables would be predicted to have complex but potentially profound effects on physiology and the trajectories of aging Conversely those eating a rich variety of plants may be more protected against accelerated aging and the diseases of aging Of these two predictions the second has been better studied and is generally supported Polyphenols consist of several classes of chemical substances including nonflavonoid compounds such as resveratrol other stilbenes and curcuminoids and classic flavonoids consisting of two large classes anthocyanins which are colorful and pigmented and anthoxantins which are colorless Resveratrol and its first cousin pterostilbene are both naturally occurring phytoalexins produced by plants in response to fungal infection phytoalexins are all plant defense compounds Of the anthoxantin family quercetin is one of the best known and best studied members along with EGCG a member of the catechins family with catechins constituting a large group of polyphenols in tea and wine Dietary sources for polyphenols include many foods that have been ancient components of the human diet for many hundreds and even thousands of years fruits and their juices typically containing both anthocyanins and anthoxantins tea catechins coffee chlorogenic caffeic and ferulic acids red wine anthocyanins resveratrol and quercetin vegetables many anthoxantins and anthocyanins some cereals chocolate multiple flavonoids including catechins and proanthocyanidins and various legumes particularly soy isoflavones and peanuts In this context there are multiple challenges to any emerging science that might explain the roles polyphenols could play in health maintenance and the slowing of at least some aspects of aging First there