3.4 Associations between dietary intakes and the gut microbiome diversity
Table 3 shows correlations between diet and the alpha-diversity indices of the gut microbiome. Total protein intake showed negative associations with Shannon’s index (P = 0.02) and Pielou’s_e index (P = 0.03); based on the calorie’s percentage, intake of carbohydrate (P = 0.07) and fiber (P = 0.07) showed trends of positive associations with Chao1. Regarding the micronutrients, the amount of beta-carotene intake had a positive correlation with Faith’s_PD (P = 0.02) and a trend of positive association with Chao1 (P = 0.08); however, the amount of selenium intake was negatively correlated with Shannon’s index (P = 0.05) and Pielou’s_e (P = 0.03), and vitamin A showed a trend of negative association with Pielou’s_e (P = 0.06).
The alpha-diversity was compared between three nutritional intake levels (inadequate, adequate, and excessive) (Table 4) . Compared with the group with inadequate carbohydrates intake, the adequate intake group had a significantly higher Chao1 (P = 0.005) and Faith’s_PD (P = 0.008), as well as a trend of higher Shannon’s index (P = 0.083). Children with adequate vitamin B6 had a higher Chao1 diversity index than children with inadequate or excessive vitamin B6 (P = 0.0004). Children with excessive selenium intake had a trend of higher Pielou’s_e index than children with inadequate selenium intake (P = 0.091).