Table 1 Specific characteristics of the seven studies included in the meta-analysis
Study | Country | Sample size (experiment/control) | Age (years) | Interventions | Administration form | Probiotic strain | Duration | Outcomes |
|---|---|---|---|---|---|---|---|---|
Mahboobi et al. [5] | Iran | 56 (28/27) | 25–65 | Probiotic/Placebo | Capsule | Lacbotacillus casei; Lacbotacillus acidophilus; Lacbotacillus phamnosus, etc. | 8 weeks | (8) |
Kassaian et al. [21] | Iran | 85 (27/30/28) | 35–75 | Probiotic/Synbiotic/Placebo | Powder | Lactobacillus acidophilus; Bifidobacterium lactis; Bifidobacterium bifidum, etc. | 24 weeks | (1)(2)(3)(4) |
Naito et al. [17] | Japan | 98 (48/50) | 20–64 | Lactobacillus casei strain Shirota/Placebo | Milk | Lactobacillus casei strain Shirota | 14–15 weeks | (1)(2)(4)(5)(6)(7)(8) |
Toshimitsu et al. [22] | Japan | 126 (62/64) | 20–64 | Lactobacillus plantarum OLL2712/Placebo | Yogurt | Lactobacillus plantarum OLL2712 | 12 weeks | (1)(2)(4) |
Yan et al. [23] | China | 72 (41/31) | 35–65 | Probiotic/Placebo | Capsule | Bifidobacterium; Lactobacillus-acidophilus; Enterococcus-faecalis | 2 years | (1)(4)(5)(6)(7)(8) |
Oh et al. [24] | Korea | 37 (20/17) | 19–70 | Lactobacillus plantarum HAC01/Placebo | Capsule | Lactobacillus plantarum HAC01 | 8 weeks | (1)(2)(3)(4) |
Stefanaki et al. [25] | Greece | 17 (7/10) | 12–20 | Probiotic/Placebo | Sachet | Streptococcus thermophilus; Bifidobacteria breve; Bifidobacteria longum, etc. | 4 months | (1)(2)(5)(6) |