Table 1.
Effect of carbohydrates on gut microbiota.
| Study | Population | Dietary Effects | Results |
|---|---|---|---|
| Costabile et al., 2008 [55] | 32 healthy volunteers with BMI between 20 and 30 kg/m2 | Consumption of either 48 g of whole grain (WG) or wheat bran (WB) for two 3-week periods, separated by a 2-week washout period | WG: ⇑ Bifidobacteria and lactobacilli No differences in SCFAs between the two groups |
| Cotillard et al., 2013 [52] | 38 with obesity and 11 overweight subjects | 12 weeks of energy-restricted high protein diet with 35% protein, 25% lipids, and 44% carbohydrates | Dietary intervention: ⇑ gene richness ⇓ Bifidobacterium and Eubacterium rectale. |
| Birkeland et al., 2020 [58] | 25 subjects with BMI < 40 kg/m2 affected by type II diabetes | 16 g of inulin-type fructans (a mixture of oligofructose and inulin) and 16 g placebo (maltodextrin) for 6 weeks in randomized order | The inuline-type fructans: ⇑ SCFAs ⇑ Bifidobacterium adolescentis |
| Sheflin et al., 2017 [59] | 29 overweight and with obesity volunteers | Consumption of a snack with fiber-rich, stabilized rice bran (30 g/day), or cooked navy bean powder (35 g/day) for 28 days | Supplementation with rice bran: ⇓ the Firmicutes to Bacteroidetes ratio ⇑ SCFAs |
| Walker et al., 2011 [60] | 14 overweight men | Volunteers were provided successively with a control diet, diets high in resistant starch (RS) (26 g/day of resistant starch from type III resistant starch), or non-starch polysaccharides (NSPs) (42 g/day of total non-starch polysaccharides from wheat bran) and a reduced carbohydrate weight loss (WL) diet over 10 weeks | RS diet: ⇑ Ruminococcus bromii (17%) of total bacteria compared to the 3.8% of the NSP diet ⇑ Eubacterium rectale (10.1%) RS and WL diets: ⇑ Oscillibacter WL: ⇓ Eubacterium and Collinsella aerofaciens |
| Abell et al., 2008 [63] | 46 overweight volunteers | One group received 4 weeks of a RS2—rich diet (22 g/day of RS) and the other one received 4 weeks of a RS2—low diet (1 g/day of RS). | The RS2-rich diet group showed ⇑ Ruminococcus bromii, Faecalibacterium prausnitzii and Eubacterium rectale |
Legend: ⇑ increase; ⇓ decrease.