Chromium does not belong in the diabetes treatment arsenal: Current evidence and future perspectives

Abstract

Chromium is considered to have positive effects on insulin sensitivity and is marketed as an adjunctive therapy for inducing glucose tolerance in cases of insulin resistance ("the glucose tolerance factor"). Case reports on patients who received prolonged parenteral nutrition indeed showed that the absence of trivalent chromium caused insulin resistance and diabetes. However, whether patients with type 2 diabetes can develop a clinically relevant chromium deficiency is unclear. This review summarizes the available evidence regarding the potential effectiveness of chromium supplementation on glycemic control (Hemoglobin A1c levels) in patients with type 2 diabetes. No studies investigating the longterm safety of chromium in humans were found. All clinical trials that have been performed had a relative short follow-up period. None of the trials investigated whether the patients had risk factors for chromium deficiency. The evidence from randomized trials in patients with type 2 diabetes demonstrated that chromium supplementation does not effectively improve glycemic control. The meta-analyses showed that chromium supplementation did not improve fasting plasma glucose levels. Moreover, there were no clinically relevant chromium effects on body weight in individuals with or without diabetes. Future studies should focus on reliable methods to estimate chromium status to identify patients at risk for pathological alterations in their metabolism associated with chromium deficiency. Given the present data, there is no evidence that supports advising patients with type 2 diabetes to take chromium supplements.

Beneficial effects of oral chromium picolinate supplementation on glycemic control in patients with type 2 diabetes: A randomized clinical study

“…In spite of controversies [3], chromium (Cr) supplementation has been studied as a co-adjuvant diabetes therapy, due to its role in glucose/insulin metabolism [4]. Chromium may enhance insulin sensitivity by activating intracellular signaling pathways involved in glucose transporter 4 (GLUT4) translocation, consequently increasing glucose and amino acids transport [5,6].…”

Nutraceutical Improves Glycemic Control, Insulin Sensitivity, and Oxidative Stress in Hyperglycemic Subjects: A Randomized, Double-Blind, Placebo-Controlled Clinical Trial

“…Upon binding chromium, it is converted to holochromodulin, which then attaches to insulin receptor to increase its own insulin binding efficiency. 44 It was predicted that biotin and Cr may synergize to create a more effective treatment for type 2 diabetes mellitus. 45 A small, open-label clinical trial demonstrated that twice daily administration of biotin and Cr in combination with a dietary education program significantly reduced HbA1c in patients with type 2 diabetes mellitus.…”

Chromium picolinate reduces insulin resistance in polycystic ovary syndrome: Randomized controlled trial

“…So far, there are still contradictory results from the available meta-analyses on the value of CrP in reducing IR in diabetic, obese or IGT patients. 8,18,19,[23][24][25][26][27] For instance, a meta-analysis concluded that chromium effects were non-relevant after stratifying the studies according to methodological quality, sponsor involvement, and a Western versus non-Western study location! 24 The latter is not a valid justification for excluding a study from a meta-analysis, given that gene, lifestyle and population variation all have an impact on the prevalence of PCOS and IR in any population.…”

“…8,18,19,[23][24][25][26][27] For instance, a meta-analysis concluded that chromium effects were non-relevant after stratifying the studies according to methodological quality, sponsor involvement, and a Western versus non-Western study location! 24 The latter is not a valid justification for excluding a study from a meta-analysis, given that gene, lifestyle and population variation all have an impact on the prevalence of PCOS and IR in any population. 28,29 While previous meta-analyses failed to show a beneficial effect of chromium supplementation, 25,26 a more recent meta-analysis suggested favorable effects of chromium on blood sugar level in diabetic patients.…”