INS and hyperinsulinism: As shown (Figure 5e,f), serum insulin levels were significantly higher at ZT15 in both male (one-way ANOVA; F(Firoc; control) = 9.21654; p = 0.01616) and female mice (one-way ANOVA; F(Firoc; control) = 12.43179; p = 0.01681), indicating that Firoc mice develop hyperinsulinemia, at least during the active phase.