There is bound to be someone doing "brown fat injection for weight loss." However, there is absolutely NO data to support such treatment. Any data you may be shown is "junk science." Mesotherapy, another method of injection to stimulate weight loss has been around for quite a few years and there is still no data to support it either. The only method of weight loss that works is diet modification. Notice I did not say diet. Diets do not work. You must gradually change what and how much you eat so that it then becomes a habit. Ancillary things that help are exercise (once you are on a reasonable diet), and, eventually, liposuction or one of the laser fat loss methods. The latter can, since it is entirely noninvasive, be used to jump start the weight loss while you are modifying your diet.