Gallates, salt or ester of gallic acid (GA) are found widely in plants as phenolic compounds. Many forms of gallates are available in plants namely, epigallocatechin-3-gallate (EGCG), epicatechin-3-gallate (ECG), epigallocatechin (EGC), GA, ethyl gallate (EG), methyl gallate, propyl gallate, gallocatechin and theaflavin-3-gallate to name a few. Among these compounds, EGCG, GA and EG have attracted many researchers around the world for their antioxidant, anticancer, antidiabetic, antiarthritic, anti-HIV and neuroprotective properties. Food sources of each compound vary from fruits, nuts, green tea and carob flour for EGCG; blueberries, apples, flax seeds, oak bark, walnut, green tea and watercress for GA; and walnuts, Terminalia chebula and T. myriocarpa for EG. The efficacy of these individual compounds varies based on their chemical structures and bioavailability in circulation. There are numerous reports available on their sole therapeutic properties using cell lines and animal models. In addition, these compounds are also reported to be used as a sensitizer or as an adjuvant to enhance the cytotoxic potential of some anticancer drugs. In this article, we have compared and compiled the beneficial effects of these compounds against major diseases like cancer, diabetes, inflammation, free radical generation and neurodegeneration using cell line, animal and human system. Compilation of the previous work carried out so far could form a basis for future research work related to identifying the mechanism behind each pharmaceutical property. Moreover, this review will give an insight in reasoning the differences in action of these compounds based on their structure-activity relationship, pharmacology and toxicology. © 2014 by Nova Science Publishers, Inc. All rights reserved.