Abstract: There is disclosed a pharmaceutical composition and method for metabolic consumption of calories and weight loss. The pharmaceutical composition is a culture of brown adipose cells, preferably encapsulated in a porous growth matrix, and a semipermeable membrane encapsulating the porous matrix wherein the semipermeable membrane has a molecular weight cutoff of at least 10,000 daltons and, preferably, a lipoprotein lipase embedded therein. Further disclosed is a pharmaceutical composition for metabolizing fatty acids into carbon dioxide, water and heat including a mammalian cell stably transfected with a DNA sequence coding for a mammalian UCP polypeptide, wherein the transfected mammalian cell transcribes and translates UCP polypeptide.