Article Text

Download PDFPDF
Milk osmolality: does it matter?
  1. Freya Pearson1,
  2. Mark J Johnson2,
  3. Alison A Leaf1,2
  1. 1Department of Neonatal Medicine, Southampton University Hospitals Trust, Southampton, UK
  2. 2NIHR Nutrition, Diet and Lifestyle Biomedical Research Unit, Southampton General Hospital, Southampton, UK
  1. Correspondence to Dr Freya Pearson, Department of Neonatal Medicine, Southampton University Hospitals Trust, Mailpoint 105, Princess Anne Hospital, Coxford Road, Southampton SO16 5YA, UK; freya.pearson{at}


High osmolality of infant feed reflects a high concentration of solute particles and has been implicated as a cause of necrotising enterocolitis. Evidence for direct intestinal mucosal injury as a result of hyperosmolar feeds is scant, and no good evidence has been found to support such an association. High osmolality of enteral substrate may, however, slow down gastric emptying. Osmolality of current infant feeds ranges from around 300 mOsm/kg in human breast milk to just more than 400 mOsm/kg in fully fortified breast milk. Addition of mineral and vitamin supplements to small volumes of milk can increase osmolality significantly and should be avoided if possible.

Statistics from

Request Permissions

If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.

Linked Articles

  • Fantoms
    Ben Stenson