Chromium
Vitaminas e mineraisÚltima revisão: 7 de abril de 2026. Abordagem de fontes: contexto padrão de interpretação laboratorial, material médico de referência e orientações clínicas ou de saúde pública quando relevantes.
O que é Chromium?
Chromium is a trace mineral that has been proposed to play a role in insulin signaling and glucose metabolism, though its status as an essential nutrient is debated. Trivalent chromium (Cr³⁺) is the biologically relevant form found in food and supplements, and it is distinct from hexavalent chromium (Cr⁶⁺), which is a toxic industrial pollutant and known carcinogen. The proposed mechanism of action involves chromodulin (also called low-molecular-weight chromium-binding substance), an oligopeptide that may potentiate insulin receptor signaling by enhancing insulin receptor tyrosine kinase activity.
The European Food Safety Authority (EFSA) removed chromium from its list of essential nutrients in 2014, concluding that evidence for biological essentiality was insufficient. However, the U.S. National Academies still recognize it as an adequate intake nutrient. Dietary sources include broccoli, grape juice, whole grains, brewer's yeast, nuts, and meat. Serum or plasma chromium measurement is technically challenging due to extremely low physiological concentrations, ubiquitous environmental contamination, and lack of standardized reference methods. Levels reflect recent intake more than long-term status.
Por que isso importa
Chromium has been widely marketed as a supplement for improving insulin sensitivity, blood sugar control, and weight management. While some clinical trials have shown modest improvements in glycemic markers in type 2 diabetes patients, particularly in populations with poor baseline chromium status, the overall evidence remains inconsistent. The most rigorous meta-analyses have shown small, clinically modest effects on HbA1c and fasting glucose. Chromium deficiency, if it truly exists as a clinical entity, would theoretically impair glucose tolerance—a condition described in early case reports of patients on chromium-free parenteral nutrition who developed insulin-resistant hyperglycemia that responded to chromium supplementation.
Faixas de referência normais
| Grupo | Faixa | Unidade |
|---|---|---|
| Adults (serum) | 0.05–0.50 | µg/L |
| Adults (urinary excretion) | 0.1–2.0 | µg/day |
As faixas de referência podem variar entre laboratórios. Sempre compare seus resultados com as faixas fornecidas pelo seu local de exame.
O que significam níveis altos de Cr
Causas comuns
- Chromium supplementation (picolinate, polynicotinate)
- Occupational exposure (chrome plating, leather tanning, stainless steel welding)
- Environmental contamination
- Chromium-cobalt joint prosthesis wear
Possíveis sintomas
- Trivalent chromium: generally low toxicity even at high oral doses
- Kidney damage at very high chronic doses
- Case reports of liver and kidney injury from chromium picolinate supplements
- Hexavalent chromium (occupational): lung cancer, nasal septum perforation, skin ulcers
O que fazer: For elevated trivalent chromium from supplements, reduce or discontinue supplementation. Monitor renal function if levels are very high. For occupational hexavalent chromium exposure, remove from exposure, monitor for respiratory symptoms, and follow occupational health guidelines for cancer screening. Chromium from joint prosthesis wear requires orthopedic evaluation. The tolerable upper limit for trivalent chromium from supplements has not been established, but caution is warranted at doses exceeding 200 µg/day.
O que significam níveis baixos de Cr
Causas comuns
- Chromium-free parenteral nutrition (historical case reports)
- Diets very low in whole grains and vegetables
- High-sugar diets (may increase chromium excretion)
- Pregnancy and lactation (increased demands)
- Strenuous exercise (increased urinary losses)
Possíveis sintomas
- Impaired glucose tolerance (described in TPN patients)
- Insulin resistance
- Elevated triglycerides and cholesterol (theoretical)
- Peripheral neuropathy (reported in TPN cases)
- Weight loss and confusion (severe, hospitalized cases only)
O que fazer: True chromium deficiency is extremely rare and has primarily been documented in patients on prolonged chromium-free parenteral nutrition. If suspected, chromium supplementation at 20–35 µg/day (the adequate intake level) through diet or supplements is reasonable. Chromium picolinate is the most studied supplemental form. Increase dietary intake through broccoli, whole grains, and brewer's yeast. Evidence does not support high-dose supplementation for glucose control in individuals with adequate chromium status.
Quando o exame de Cr é recomendado?
- In occupational health screening for chromium-exposed workers
- When evaluating patients with chromium-cobalt joint prostheses
- Rarely ordered for nutritional assessment (limited clinical utility)
- In research settings studying glucose metabolism
- When parenteral nutrition-related glucose intolerance is suspected
Perguntas frequentes
Biomarcadores relacionados
Leitura relacionada
Condições
Referências e abordagem de revisão
As páginas do glossário de biomarcadores são explicações educativas e devem ser interpretadas junto com as faixas de referência e observações fornecidas pelo seu laboratório e pelo seu médico. Para conhecer nossos padrões editoriais e processo de revisão, veja nossa Política editorial e a nossa revisão de conteúdo.
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Enviar resultados de exames →Aviso médico: Estas informações são apenas educativas e não substituem orientação, diagnóstico ou tratamento médico profissional. As faixas de referência podem variar entre laboratórios. Sempre converse com seu profissional de saúde sobre a interpretação dos seus resultados específicos.