Effects of zinc and probiotic co-supplementation on inflammation, gastrointestinal symptoms, quality of life, and mood in irritable bowel syndrome patients

Zinc supports intestinal integrity, and probiotics restore microbial balance, thereby improving gut health. This study examined the effect of zinc and probiotic co-supplementation on inflammation, gastrointestinal symptoms, quality of life (QoL), and mood in IBS patients. The 84 participants were assigned to three groups and received: (1) a zinc gluconate tablet (20 mg elemental zinc) and a placebo; (2) a zinc gluconate and a probiotic capsule; (3) 2 placebos as a control for 90 days. The serum zinc and TNF-α, IBS severity, mood, and QoL were assessed by validated methods. Supplementation with zinc, without or with probiotics, improved serum zinc (6.36 ± 0.80 and 13.03 ± 3.82, vs. -1.76 ± 1.82 µg/dL; p = 0.008), and IBS severity (-182.85 ± 16.27 and − 195.71 ± 23.46, vs. -73.21 ± 17.69; p = 0.003) compared to placebo. Depression (− 3.62 ± 1.46 or − 0.78 ± 1.16 vs. 2.07 ± 1.53, p = 0.004) and stress scores (-2.88 ± 1.82 or -2.64 ± 1.49, vs. 1.85 ± 1.95, p = 0.013) decreased after zinc or placebo supplements compared to zinc plus probiotic. Zinc supplementation, with or without probiotics, improved serum zinc levels and GI symptoms in IBS, whereas zinc alone was more effective than zinc plus probiotics in reducing depression and stress scores. Further research is suggested to confirm our findings.