Trace element



Dietary sources

Causes deficiency

Risk groups

Clinical findings

Screening and management


Metabolism of fats and carbohydrates

Muscle meat, grain, legumes, nuts

Restricted food access

Extremely rare,

parenteral nutrition (PN)


Impaired glucose tolerance, weight loss, confusion, peripheral neuropathy

Levels more commonly checked for excess (e.g. in PN dependent patients), ubiquitous in food, no dosing needed


Mineral cofactor superoxide dismutase, enzymes related to electron transfer, iron oxidation, melanin formation and connective tissue synthesis

Organ and muscle meat, nuts, cereals,

Long term PN without Cu added

Extremely rare,



Impaired glucose tolerance, weight loss, confusion, peripheral neuropathy, anaemia, neutropenia

Malnutrition, PN dependent patients



Component of thyroid hormones required for normal growth and development

Sea fish, seaweed, iodised salt, dairy (through cattle supplementation)

Environmental deficiency in inland Africa and Asia, Sth America, mountainous areas WHO map iodine

Absorbed stomach and upper SI

Environmental deficiency in inland Africa and Asia

Goitrogens can impair binding of I to thyroglobulin (brassicas, sweet potato, maize)

Hypothyroidism (lethargy, poor cold tolerance, bradycardia, goitre), cretinism (intellectual disability (reduced language and memory skills), deaf-mutism, +/- hypothyroidism, short stature), miscarriage, stillbirth, increased perinatal mortality.

24h urine iodine excretion (90% excreted via kidneys) or random urine iodine:creatinine


Iodised salt

Mx - Mx thyroid disease


Component in heme and cytochrome proteins

Organ and muscle meat, pulses, dried apricots, green leafy vegetables

Restricted food access, increased losses, including parasite infection (inc. hookworm), malaria

Young children, esp those born to deficient mothers, high milk intake, vegetarians,

chronic disease, PN dependent

Microcytic anaemia, pallor, weakness, shortness of breath

See anaemia and iron deficiency guideline


Component metalloenzymes, bone formation, metabolism protein, carbohydrate, cholesterol

Cereals, tea, vegetables, low ferritin levels increase absorption, low bile excretion reduces excretion

Clinical deficiency not usually seen, even with low dietary intake if otherwise healthy.

Extremely rare


Impaired growth, reproductive function and glucose tolerance

Levels more commonly checked for excess (e.g. in PN dependent patients) See NRV


Enzyme cofactor, including for purines/pyridines

Legumes, grains, nuts

Clinical deficiency not usually seen, reported in long term PN without Mb added.

Extremely rare


Neurological impairment in genetic abnormality sulphite oxidase

Levels not usually checked



Antioxidant, redox reactions, thyroid metabolism (conversion T4 to T3), glutathione peroxidase

Seafood, chicken, muscle meat, fish, brazil nuts, eggs. Cereals and plant food content reflect soil content

Areas where soil levels low, gut disease

Seen in parts of China, Finland (soil content low)

Cardiomyopathy (Keshan disease, affects mostly children and women), myositis and nail dystrophy

Screen if malnutrition, PN dependent, See NRV


Cofactor for many enzymes, including ALP, RNA/DNA polymerase and superoxide dismutase

Seafood, organ and muscle meat, grains, milk, eggs. Higher bioavailability from animal sources than plant foods

Restricted food access, increased losses

Restricted food access, any cause of chronic diarrhoea, chronic illness

Acrodermatitis enteropathica, delayed wound healing, impaired taste, growth failure, delayed puberty and diarrhoea

Screen if malnutrition, diarrhoea, PN dependent, features deficiency See NRV, treatment deficiency: 1mg/kg/d in 1-3 doses, repeat levels after 1m