Polycrystalline diamond cutting elements having enhanced thermal stability, drill bits incorporating the same, and methods of making the same are disclosed herein. In one embodiment, a cutting element includes a substrate having a metal carbide and a polycrystalline diamond body bonded to the substrate. The polycrystalline diamond body includes a plurality of diamond grains bonded to adjacent diamond grains by diamond-to-diamond bonds and a plurality of interstitial regions positioned between adjacent diamond grains. At least a portion of the plurality of interstitial regions comprise lead or lead alloy, a catalyst material, metal carbide, or combinations thereof. At least a portion of the plurality of interstitial regions comprise lead or lead alloy that coat portions of the adjacent diamond grains such that the lead or lead alloy reduces contact between the diamond and the catalyst.