Adipose tissue is the most abundant endocrine organ in humans with an important influence on many events throughout life. Many studies that highlight the different phenotypic characteristics of fat cells in adults are becoming more frequent. Perhaps, one of the most important properties of fat cells is their flexibility to adapt to different environmental and nutritional conditions. White adipocytes can receive hormonal stimuli from other tissues and differentiate into cells with a greater thermogenic potential. In this process, lipid inclusion changes and the number of mitochondria increases, leading to functional characteristics similar to those of brown adipocytes. Recently, beige fat cells have been studied in the attempt to elucidate their role in the regulation of obesity and insulin resistance. Therefore, understanding the beige adipocyte embryonic origin and the ability of these cells to transdifferentiate is a major research challenge, with the aim of elucidating the role of these cells as a possible therapeutic strategy for obesity and metabolic diseases. In this manuscript, we will focus on the origins of the different fat cells and the possible therapeutic properties of beige fat cells.