We have demonstrated so far that the excretion of acetone bodies in healthy subjects is dominated by the presence of certain quantities of carbohydrates in the food. We have also called attention to the theory that the appearance of these bodies in the urine is the result of some perversion of oxidation. This leads us to the further assumption that there must be some inter-relationship between the absence of carbohydrates from the food and perversions of oxidation. These hypothetical disturbances of oxidation could, for instance, produce noncombustion of acetone bodies that are normal intermediary products of metabolism, in the sense that in the absence of carbohydrates they would not be burnt to C02 and H20. This view is favored by the fact that a healthy person living on a mixed diet can destroy B-oxybutyric acid and diacetic acid completely, and can also destroy the greater portion of any acetone that may be administered. Another view would be that in the absence of sufficient carbohydrate metabolism would be perverted in such a way that the acetone bodies would be produced as new bodies, i. e., as abnormal products of metabolism. We have no definite and direct data to prove the latter assumption. The view that the acetone bodies are an intermediary product of normal metabolism seems to agree more with the facts we possess.