Zinc deficiency may be due to dietary lack, total parenteral nutrition without zinc supplementation, or as part of a generalised malabsorption. Rarely there is a genetic basis - acrodermatitis enteropathica.

Clinical features:

• diarrhoea
• alopecia
• poor wound healing
• defective taste
• failure to thrive
• the syndrome of acrodermatitis enteropathica

Diagnosis is made by giving a therapeutic trial of zinc tablets; plasma levels are an unreliable indicator of zinc deficiency because the plasma level may be lowered, for example, in acute infection and after trauma.