This is not metabolizable, but acetoacitate. And D three hydroxybuty can be broken down by ourselves to form energy molecules, as we'll see in just a moment. Now, this process requires NADH because it's a reduction step. Acetone acetate is reduced into this product by using NADH inside our liver. Now, what determines the concentration at equilibrium of these two molecules? So do we have more of aceto acetate, or do we have more of this product?