Patient-Friendly Explanation

Anaemia means not having enough healthy red blood cells, which causes tiredness and breathlessness. People with obesity, and especially those who have had weight-loss surgery, are more likely to develop it.

Clinical Definition

Obesity is associated with iron deficiency anaemia through chronic low-grade inflammation and hepcidin-driven iron sequestration, and with deficiency of vitamin B12, folate and vitamin D. After bariatric surgery the risk rises sharply because gastric acid and intrinsic factor production fall and duodenal iron absorption is bypassed or reduced.

Why It Matters

Fatigue in a patient with obesity or a bariatric history should prompt a full blood count with iron studies, B12 and folate. Correcting anaemia restores the energy needed for physical activity and is a routine part of metabolic surgery follow-up.