Discovering a cell type with the highest efficiency and the least side-effects is one of the priorities of scientists active in this field. Of all the cells, mesenchymal stem cells have been and still are of interest to the researchers for use in pre-clinical and clinical studies due to being easily accessible, pluripotency, secretion of numerous growth factors, low risk of immunological rejection, and not having ethical issues for clinical use. Of all mesenchymal cells, human adipose-derived stem/stromal cells (hADSCs) are more safely and easily accessible, produce more growth factors compared to other mesenchymal stem cells, have the ability to differentiate to various cell lines, secrete high levels of angiogenic factor and their feasibility, safety and efficacy have been confirmed. Therefore, in the last decade, it has received more attention from researchers, compared to other cell sources. Since distribution and function of adipose tissue is versatile and changes at any age during the lifetime, it is expected that at different ages, hADSCs also show different functions and abilities. Therefore, it is hypothesized that autologous implantation is not necessarily always the best choice. Autologous transplantation of hADSCs is only the best choice in ages that these cells have the optimum efficacy. If it is determined in what age these cells have the highest efficacy, choosing the type of implantation will be an important factor in achieving the best response to treatment.