Table 1.
Characteristics of included studies in the meta-analysis
| Ref. | Design | Participants, age (yr), sex, case/control (n) | Intervention | Dose/ Duration |
Outcome measures | Jadad Score | |
|---|---|---|---|---|---|---|---|
| Case | Control | ||||||
| Ejtahed et al., 2012 [14] | DB-RCT | T2DM, 30–60, both, 30/30 |
Probiotic yogurt: L. acidophilus La5, Bifidobacterium lactis Bb12 |
Conventional yogurt | 300 g daily/ 6 w | Anthropometric, FBS, FSI, HbA1C, oxidative stress biomarkers | 5 |
| Asemi et al., 2013 [10] | Cross-over DB-RCT | T2DM, 35–70, both, 27/27 |
7 viable & freeze-dried strains: L. acidophilus, L. casei, L. rhamnosus, L. bulgaricus, Bifidobacterium breve, B. longum, Streptococcus thermophilus |
Placebo | One capsule daily/ 8 w | Anthropometric, FBS, FSI, HOMA-IR, HbA1C, oxidative stress biomarkers, hs-CRP, lipid profile | 4 |
| Mazloom et al., 2013 [22] | SB-RCT | T2DM, 25–65, both, 16/18 |
L. acidophilus, L. bulgaricus, L. bifidum, L. casei |
Placebo | One capsule twice daily/ 6 w | Anthropometric, FBS, FSI, HOMA-IR, oxidative stress biomarkers, hs-CRP, lipid profile, inflammatory markers | 3 |
| Asemi et al., 2014 [27] | Cross-over DB-RCT | T2DM, 35–70, both, 62/62 | Synbiotic food: probiotic viable & heat-resistant Lactobacillus sporogenes, inulin as prebiotic | Same food without probiotic bacteria & prebiotic inulin | 3 times daily/ 6 w | Anthropometric, FBS, FSI, HOMA-IR, HbA1C, oxidative stress biomarkers, hs-CRP, lipid profile | 4 |
| Asemi et al., 2016 [28] | Cross-over DB-RCT | T2DM, 35–70, both, 51/51 |
Synbiotic food: L. sporogenes, inulin, beta-carotene |
Same food without probiotic, inulin, and beta-carotene | 3 times daily/ 6 w | Anthropometric, FBS, FSI, HOMA-IR, oxidative stress biomarkers, hs-CRP, lipid profile, liver enzymes | 4 |
| Bahmani et al., 2016 [29] | DB-RCT | T2DM, 35–70, both, 27/27 |
Synbiotic bread: probiotic viable & heat-resistant L. sporogenes, inulin |
Control bread | 3 times daily/ 8 w | Anthropometric, oxidative stress biomarkers, liver enzymes | 4 |
| T2DM, 35–70, both, 27/27 |
Probiotic bread: probiotic viable & heat-resistant L. sporogenes |
||||||
| Miraghajani et al., 2017 [30] | Parallel SB-RCT | T2DM, 32–68, both, 20/20 |
Probiotic soy milk: L plantarum A7 |
Soy milk | 200 ml daily/8 w | Anthropometric, oxidative stress biomarkers | 4 |
| Soleimani et al. 2017 [31] | Parallel DB-RCT | DN (T1DM & T2DM), 36–75, both, 30/30 |
Capsule: L. acidophilus, L. casei, Bifidobacterium bifidum |
Placebo | One capsule daily/12 w | FBS, FSI, HOMA-IR, HbA1C, oxidative stress biomarkers, hs-CRP | 3 |
| Tonucci et al. 2017 [32] | DB-RCT | T2DM, 35–60, both, 23/22 | Fermented milk: L. acidophilus La5, Bifidobacterium animalis subsp. lactis Bb12 | Conventional fermented milk | 120 g daily/6 w | Anthropometric, body composition, lipid profile, inflammatory markers, oxidative stress biomarkers, FBS, HOMA-IR, HbA1C, fecal samples | 5 |
| Mafi et al. 2018 [33] | Parallel DB-RCT | DN (T1DM & T2DM), 45–85, NA, 30/30 |
Probiotic capsule: L. acidophilus, Bifidobacterium bifidum, L. reuteri, L. fementum |
Placebo | One capsule daily/12 w | FBS, HOMA-IR, HbA1C, lipid profile, hs-CRP, BUN, Cr, urine protein, inflammatory markers, oxidative stress biomarkers | 4 |
| Mazruei et al., 2018 [34] | Parallel DB-RCT | DN (T1DM & T2DM), 45–85, NA, 30/30 |
Probiotic honey: Bacillus coagulans T4 |
Honey | 25 g daily/ 12 w | FBS, HOMA-IR, lipid profile, hs-CRP, BUN, Cr, urine protein, inflammatory markers, oxidative stress biomarkers | 4 |
| Mohseni et al., 2018 [35] | Parallel DB-RCT | DF (T1DM & T2DM), 45–85, both, 30/30 |
Probiotic capsule: L. acidophilus, Bifidobacterium bifidum, L. casei, L. fementum |
Placebo | One capsule daily/12 w | FBS, HOMA-IR, lipid profile, hs-CRP, HbA1C, wound characteristics, inflammatory markers, oxidative stress biomarkers | 4 |
| Raygan et al., 2018 [36] | Parallel DB-RCT | T2DM, 40–85, NA, 30/30 |
Probiotic capsule: L. acidophilus, Bifidobacterium bifidum, L. casei, L. fementum |
Placebo | One capsule daily/12 w |
Anthropometric, FBS, HOMA-IR, lipid profile, hs-CRP, inflammatory markers, oxidative stress biomarkers |
5 |
Legend: SB-RCT: Single blind randomized clinical trial; DB-RCT: Double blind randomized clinical trial; DN: Diabetic nephropathy; DF: diabetic foot; W: Week; FBS: Fasting blood sugar; HOMA-IR: Homeostasis model of assessment-insulin resistance; HbA1C: Hemoglobin A1C; FSI: Fasting serum insulin; hs-CRP: High sensitivity C - reactive protein; BUN: blood urea nitrogen; Cr: Creatinine; NA: Unknown