Can chromium supplements improve blood sugar control in patients with type 2 diabetes?

This review looked at the effect of chromium supplements for patients with type 2 diabetes (T2D). It found that chromium supplements improved blood glucose and insulin levels for these patients.

T2D is a condition in which the body does not respond well to the hormone insulin, which controls the amount of glucose (sugar) in the blood. The pancreas tries to make more insulin to compensate for this lack of sensitivity, but eventually, the pancreas cannot make enough.

Patients with T2D have lower levels of magnesium, zinc, and several vitamins. These nutrients and antioxidants may protect the pancreas. Chromium is another mineral that is active in the body. Chromium is used by a protein that moves glucose out of the blood. It also improves the way the body recognizes glucose. It is not clear whether chromium supplements can improve glucose control for patients with T2D.

This analysis included 23 studies of patients with T2D. Each study randomly assigned some patients to take chromium supplements, and others to take a placebo (inactive pills). The types of supplements included chromium picolinate, chromium chloride, and chromium yeast. The doses of chromium were between 50 and 1000 ug/day. Patients were followed for between 4 and 25 weeks.

Chromium supplements lowered blood glucose levels after not eating (fasting glucose levels) by 19.00 mg/dl. This improvement was significant at both low and high doses of chromium. 

The analysis also looked at the effect of taking chromium for at least 12 weeks. Chromium significantly lowered insulin by 12.35 pmol/l. Glycated hemoglobin (HbA1c), which is a measure of overall blood sugar control, was significantly reduced by 1.70%. 

HOMA-IR is an estimate of whether the pancreas can make enough insulin. HOMA-IR significantly improved for patients taking chromium for 12 weeks (decrease of 1.53).

This review found that chromium supplements improved glucose control and sensitivity to insulin for patients with T2D.

The included studies used daily doses of chromium between 50 and 1000 micrograms per day. The review found that doses over and under 200 micrograms were both effective. It is not clear what the best dose of chromium is for patients with T2D.