“…Single-strain probiotic was used in 21 RCTs: Bifidobacteria [ 36 , 44 , 46 , 47 , 56 , 57 , 60 , 62 , 65 ], Lactobacillus [ 34 , 35 , 37 , 38 , 45 , 53 – 55 , 61 , 63 , 64 , 67 ] and Saccharomyces [ 42 , 49 , 51 , 59 ]. Multi-strain probiotic was used in nine RCTs including one that used two Bifidobacterium strains from same genus [ 41 ], whereas eight used a combination of probiotic strains from different genera [ 39 , 40 , 43 , 48 , 50 , 52 , 58 , 66 , 68 ].…”