TABLE 1.

Main causes of zinc deficiency

Mechanism	Individual causes
Reduced/inadequate intake	GI disease: Crohn's disease, jejunoileal bypass, previous bariatric surgery, small bowel resection, acrodermatitis enteropathica, alcoholic pancreatitis, cystic fibrosis
Reduced absorption	Low dietary zinc, inadequately supplemented nutrition, diet rich in phytate, sodium polyphosphate or EDTA
Increased zinc losses	Inflammatory bowel disease, diarrhea, steatorrhea, enterostomy, fistula, chyle leaks: skin burns; urine losses: burns, trauma, sepsis, renal disease, alcoholism, drugs (e.g., thiazides, penicillamine, diethylenetriamine pentacetate, valproate, angiotensin‐converting enzyme inhibitors, angiotensin receptor blockers, EDTA‐containing propofol and chelating agents, cysteine, cisplatin, estrogen, oral contraceptive pill, corticosteroids), hemodialysis (namely, hemofiltration)
Increased zinc demand	Systemic illness: inflammatory response (e.g., sepsis, ARDS, COVID‐19); pregnancy, lactation