2026 Volume 2 Issue 1 Pages 230-244
Background: In schizophrenia, negative symptoms, cognitive impairment, drug-induced adverse effects, r educed daily functioning, and physical comorbidity overlap, so that biased eating behaviour and gastrointe stinal symptoms are easily overlooked. Constipation, bloating, poor appetite, chronic diarrhoea, and dyspe psia are seldom reported spontaneously and may emerge as deficiency or reduced utilisation of iron, zinc, magnesium, and vitamin D.
Objective: This review organises the digestive and absorptive problems that are easily overlooked in the c are of schizophrenia, focusing on the assessment of iron, zinc, magnesium, and vitamin D, and presents his tory-taking, laboratory testing, interpretation, and intervention procedures applicable to psychiatric outpati ent practice, together with an approach to multidisciplinary nutritional and gastrointestinal care.
Content: Iron deficiency can overlap with fatigue, impaired concentration, and irritability; because ferritin rises with inflammation, it should be read together with the complete blood count, MCV, serum iron, TIB C, TSAT, and CRP. Zinc relates to taste, appetite, skin, and wound healing, but body status cannot be judge d from serum zinc alone. Magnesium matters for neuromuscular function, electrolytes, bowel movement, a nd drug interactions, yet evidence for a direct effect on schizophrenia symptoms is scarce. Vitamin D is wo rth assessing for bone, muscle strength, sun exposure, physical activity, and metabolic risk, but supplement ation shows inconsistent psychiatric benefit.
Conclusion: Fatigue, reduced motivation, cognitive decline, low physical activity, and physical complaints in schizophrenia may be modified not only by psychiatric symptoms and drug-induced effects, but also by digestive and absorptive problems and nutritional deficiency. Assessment should combine diet, bowel habi t, gastrointestinal symptoms, medication, comorbidity, and blood tests. A multidisciplinary approach is cent ral: physicians, nurses and visiting nurses, pharmacists, registered dietitians, and psychiatric social workers share defined roles and collaborate with internal medicine and gastroenterology as needed. Feasible dietar y support by allied health professionals, including attention to bowel habit and the gut, can complement—b ut not replace—standard treatment.
