LAUSR

We read with great interest the article by Bennet et al 1 that investigated the impact of dietary shifts on gut microbiota. Together with several recent studies,2–5 they have shown that short-term dietary shifts can alter the composition of gut microbiota for both patients and healthy humans. However, these works drawn the conclusion with only a few time points and the subjects under investigation had undergone just one dietary shift. The dynamic patterns of microbial communities across longer time scales with multiple dietary shifts remain unclear. In this study, we recruited a Chinese volunteer team (VT) composing of 10 people who departed from Beijing, conducted a long stay of 6 months in Trinidad and Tobago (TAT) and returned to Beijing. Their faecal samples (188 samples), together with detailed dietary information, were collected using a high-density longitudinal sampling strategy (19 time points on average for VT members). We partitioned the whole longitudinal study into six phases: T1 represents pre-travel phase (20 samples), T2 (28 samples), T3 (60 samples) and T4 (21 samples) represent three time-slots when VT stayed in TAT, and T5 (35 samples) and T6 (20 samples) represent two time-slots after VT returned to Beijing. Meanwhile, we also collected samples from healthy natives of Beijing (BJN, 57 samples), TAT healthy natives (TTN, 28 samples), TAT patients (TTP, six samples) and TAT Chinese (TTC, eight samples) as control datasets. Finally, we sequenced the V4 …