The composition of intestinal microbiota of UTC and LVC. The relative contributions of dominant phyla (A), families (B), and the Firmicutes to Bacteroidetes ratio (C) identified from pyrosequencing data are shown. LVC, longevity village communities; UTC, urbanized town communities. All values are indicated as the mean ± SD. *, p < 0.1 and **, p < 0.05 compared with UTC children; ††, p < 0.05 compared with UTC 40′s; ‡‡, p < 0.05 compared with UTC 50′s.