HAMP and obesity due to melanocortin 4 receptor deficiency: [3], [10], [11] One US study analysed serum hepcidin and reported it to be significantly higher in bariatric surgery candidates compared to non-obese women. [3] Severe obesity however, is frequently associated with comorbidities (e.g. obstructive sleep apnoea, gastro-oesophageal reflux and fatty liver disease) that influence haematological markers or increase blood loss, [5], [12], [13] and findings from this study may not be applicable to the wider population of less severely obese young women who are not burdened with comorbid conditions.