Low thyroid function may indicate a need for carnitine to help overcome low energy levels and the tendency to gain weight. Carnitine can improve insulin sensitivity in those with type 2 diabetes. Kidney dialysis rinses away amino acids, causing weak, tired condition, which is threatened by high triglycerides. Carnitine supplements may be advisable in such situations. Carnitine combines with enzymes found in the mitochondrial membrane to transport fatty acids into the interior of the mitochondria, where they are oxidized to provide fuel for the generation of energy. In the absence of carnitine, fatty acids are not oxidized, but, instead, are transformed into dangerous triglycerides.