Chromium's status as an essential nutrient is debated, and isolated dietary deficiency has never been definitively documented in healthy people. The few documented cases were patients on long-term TPN who developed insulin resistance reversed by chromium supplementation. Chromium is sold heavily as a 'blood sugar' supplement, but evidence for benefit in non-deficient people is weak.
Common symptoms
Documented chromium deficiency in humans is extremely rare and limited to TPN cases
Insulin resistance, impaired glucose tolerance
Unexplained weight loss
Confusion or impaired cognition
Peripheral neuropathy
Note: blood sugar issues in the general population almost always have causes other than chromium status
At-risk groups
People on long-term parenteral nutrition without chromium (only documented cases)
Note: insulin resistance, prediabetes, and type 2 diabetes are NOT chromium deficiency states
There are no validated lab tests reliably indicating chromium deficiency in the general population
When to see a doctorIf you have blood sugar concerns, insulin resistance, or diabetes, the evidence-based interventions are diet, exercise, weight management, and (when needed) metformin or other prescribed medications — NOT chromium supplements. The 2020 meta-analysis cited on this page did find modest improvements in blood sugar markers in people with type 2 diabetes, and its authors said the results might support chromium use. Even so, chromium is at most an addition to medical care, never a replacement for it. If you have actual symptoms of insulin resistance, see a doctor for proper evaluation.