“…We have invited international experts, researchers and authors to submit original research and review articles that address the progress and our current understanding of nutraceuticals/supplements from in vitro and in vivo studies, as well as from clinical trials describing the benefits/adverse effects with underlying mechanisms. This Special Issue presents a compendium of excellent laboratory and clinical studies using plant extracts [ 15 , 16 , 17 , 18 , 19 , 20 ], purified compounds [ 21 , 22 , 23 ], modified formulations [ 22 , 24 ], and probiotics [ 25 , 26 , 27 , 28 ] to improve many health conditions, including metabolic disorders [ 17 , 20 ], cardiovascular disease [ 29 ], muscle metabolism [ 18 , 25 ], obesity [ 16 , 17 , 20 ], neurological disorders [ 30 ], infectious diseases [ 26 , 27 ], aging [ 23 ], and cancers [ 18 , 21 , 24 , 31 ].…”