Serum insulin levels increased by approximately 4-fold in WT mice fed the HFD, but were unaffected in the Cyp1b1-ko mice (Table 1). The fasted blood glucose levels were significantly lower in Cyp1b1-ko mice than WT mice on the LFD. The HFD challenge increased levels in WT mice by 30 percent, while the Cyp1b1-ko animals remained unchanged (Figure 3A and Table 1).