What was reviewed?
This review article systematically examines the relationship between dietary nickel exposure and systemic contact dermatitis, particularly in individuals already sensitized to nickel. The authors present three illustrative case reports and synthesize key findings from multiple experimental and clinical studies investigating the effects of dietary nickel on dermatitis flare-ups. The review also critically evaluates the mechanisms of nickel absorption, metabolism, and immune response, while providing dietary recommendations for managing nickel-induced dermatitis. It addresses both the clinical presentation and practical aspects of reducing dietary nickel intake, including food sources, preparation methods, and the role of dietary components such as vitamin C and iron.
Who was reviewed?
The review focuses on individuals with nickel allergy, specifically those with a history of allergic contact dermatitis confirmed by positive nickel patch testing. The evidence summarized spans several populations: adult and pediatric patients with hand eczema, generalized pruritus, and widespread dermatitis, all with varying histories of nickel exposure and dietary habits. The studies referenced include controlled oral challenges, dietary interventions, and trials of nickel chelation therapy in nickel-sensitive patients. In addition, the article includes three new case reports of patients with chronic or recurrent dermatitis linked to dietary nickel, who demonstrated clinical improvement after adhering to a low-nickel diet.
Most Important Findings
| Aspect | Details / Findings |
|---|---|
| Clinical Effects | Dietary nickel can trigger systemic contact dermatitis in sensitized individuals, ranging from localized hand eczema to generalized eczematous eruptions. |
| Dose-Response | 0.3 mg nickel sulfate hexahydrate → reactions in 40% of sensitive subjects; 4 mg → 70% reactions, 60% with widespread eruptions. Gradual exposure may induce tolerance in some individuals. |
| Clinical Features | Avoid high-nickel foods: whole grains, legumes, nuts, chocolate, canned foods, certain vegetables, and shellfish. Consider adjuncts: vitamin C, iron-rich diets to reduce absorption. |
| Dietary Management | Avoid high-nickel foods: whole grains, legumes, nuts, chocolate, canned foods, certain vegetables, shellfish. Consider adjuncts: vitamin C, iron-rich diets to reduce absorption. |
| Environmental Sources | Tap water, stainless steel cookware. |
| Therapeutic Strategies | Chelating agents (e.g., disulfiram) for refractory cases; caution due to hepatotoxicity risk. |
Key implications
For heavy metal certification programs like HTMC, this review emphasizes the significance of dietary and environmental nickel, beyond direct dermal exposure, in patient safety and risk assessment. The findings support standardized guidelines for permissible nickel levels in food, water, cookware, and supplements. Regulators and manufacturers should consider nickel leaching from processing equipment and packaging, as even minimal amounts can trigger systemic reactions in sensitized individuals. The data also underscore the need for accurate labeling and consumer education on hidden dietary nickel sources. Clinically, the review reinforces low-nickel diets for sensitized patients and provides evidence-based strategies to mitigate exposure.
Citation
Zirwas, M. J., & Molenda, M. A. (2009). Dietary nickel as a cause of systemic contact dermatitis. Clinical Contact Dermatology, 2(6), 39–43.
Nickel is a widely used transition metal found in alloys, batteries, and consumer products that also contaminates food and water. High exposure is linked to allergic contact dermatitis, organ toxicity, and developmental effects, with children often exceeding EFSA’s tolerable daily intake of 3 μg/kg bw. Emerging evidence shows nickel crosses the placenta, elevating risks of preterm birth and congenital heart defects, underscoring HMTC’s stricter limits to safeguard vulnerable populations.
Nickel is a widely used transition metal found in alloys, batteries, and consumer products that also contaminates food and water. High exposure is linked to allergic contact dermatitis, organ toxicity, and developmental effects, with children often exceeding EFSA’s tolerable daily intake of 3 μg/kg bw. Emerging evidence shows nickel crosses the placenta, elevating risks of preterm birth and congenital heart defects, underscoring HMTC’s stricter limits to safeguard vulnerable populations.