Lipogenesis From Carbohydrate in the Negative Caloric Balance State Induced by Exposure to Cold

¹ From the Physiology Department, Tufts University School of Medicine, Boston, Massachusetts

The ability of rats exposed to 0–2°C for 1 or 2 days to incorporate dietary glucose isotopic carbon into fatty acids was studied. Under these circumstances, in spite of a large intake of food, there is a loss in body weight and fatty acids. Whether calculated on a percentage or an absolute basis, there is under the conditions a considerable incorporation of the label into fatty acids. It is concluded that not only in the steady state, but also in a state of negative caloric balance, lipogenesis is one of the obligatory pathways of carbohydrate metabolism.