After 12-week intervention, the level of HOMA-β was significantly increased in both groups (B). However, the levels of HOMA-IR and ISI were only improved in Wuling capsule group (A and C). When compared with placebo group, the levels of HOMA-IRI, HOMA-β and ISI showed no statistically changes (A–C). Comparisons before and after intervention within the groups: *P < 0.05; vs Placebo group: ^#P < 0.05.