<qa>  What is the aim of the study to determine if cells that were not previously believed to contributeIn order to design new programs to help prevent weight gain, promote successful and sustainable weight loss, and help treat diseases related to obesity, the investigators need a better understanding of why accumulating fat in certain regions of the body is bad for health. It is known that not all fat cells are the same, but it was recently discovered that some fat cells may arise from stem cells that come from the bone marrow bone marrow progenitors, a previously unrecognized origin. This discovery has been paradigm shifting, because dogma has long held that all white fat cells arise from fat tissue resident mesenchymal stem cells. This is also important because fat cells arising from the bone marrow lineage may be linked to worse health outcomes. The aim of this study is to determine if cells that were not previously believed to contribute to fat generation in humans are indeed capable of becoming fat cells. To answer this question the investigators will take samples of cells from the blood and the fat tissue of younger and older men and women, isolate the cells that came from the bone marrow and grow them in culture to determine if they will turn into fat cells. The results of this investigation may reveal potential mechanistic targets for future therapies to reduce the negative health outcomes associated with obesity related chronic diseases. 