The effect of guar gum consumption on the lipid profile in type 2 diabetes mellitus: a systematic review and meta-analysis of randomized controlled trials

Dyslipidemia is a common encounter in type 2 diabetes mellitus (T2DM) and the current strategies to manage it are still suboptimal. Subsequently, identifying newer molecules with lipid-lowering effects is necessary. A great deal of attention has been given in recent years to fiber supplements, e.g., guar gum. Thus, we screened and evaluated the quality of the evidence regarding the benefits of guar gum supplementation in T2DM and conducted a meta-analysis to assess the effects of this compound on serum lipids in T2DM. We conducted a comprehensive search in PubMed/Medline, Web of Science, Scopus, Google Scholar and Embase, from the inception of these databases until January 2021. In total, 11 papers were included based on the eligible criteria in our meta-analysis. The meta-analysis of the eligible trials demonstrated a significant reduction of total cholesterol (TC) (WMD: -20.32 mg/dL, 95% CI: -27.02, -13.62, P < 0.001) and low-density lipoprotein cholesterol (LDL-C) (WMD: -14.52 mg/dL, 95% CI: -20.69, -8.35, P < 0.001) following guar gum supplementation in T2DM patients. The subgroup analysis based on the dosage (g/day) of this compound revealed that >= 20 g/day of guar gum led to a notable decrease in triglyceride (TG) levels (WMD: -12.55 mg/dL, 95% CI: -23.72, -1.37, P = 0.02) versus < 20 g/day (WMD: -1.84 mg/dL, 95% CI: -32.18, 28.49, P = 0.90). Guar gum supplementation had no effects on high-density lipoprotein cholesterol (HDL-C) (WMD: 0.66 mg/dL, 95% CI: -0.95, 2.28, P = 0.42). Guar gum consumption has lipid-lowering effects when administered to patients with type 2 diabetes mellitus and it is particularly able to reduce TC, LDL-C and TG levels. Further research is however needed to confirm our findings.