Supplementing preterm infants with omega-3 fats of no benefit

A research project led by the South Australian Health and Medical Research Institute (SAHMRI) and the Women’s and Children’s Hospital questions the benefits of omega-3 fats in premature infants.

The study, ‘N3RO’, the largest of its type, was a collaboration between 13 major hospitals in Australia, New Zealand and Singapore and involved over 1200 babies born more than 11 weeks early. Published today in the world’s top medical journal, the New England Journal of Medicine, the study was designed to test if supplementation with high-dose omega-3 docosahexaenoic acid (DHA), which has anti-inflammatory activity, would reduce the incidence of bronchopulmonary dysplasia (also known as chronic lung disease).

The reason for N3RO

Most babies born very preterm need extra oxygen and help with their breathing.  This can result in inflammation of the lungs causing chronic lung disease and poor long-term health outcomes. 

Very preterm babies are also born with low DHA levels that continue to fall after birth.  The outcomes of previous studies suggested that chronic lung disease could be reduced if the amount of DHA in their diet was increased to that which the baby would have received from the placenta if they weren’t born several months too early; this is more than 3 times the amount of DHA in breast milk or premature baby formula. 

The Adelaide team set out to determine if extra DHA was needed. Very preterm infants were given either a supplement providing extra DHA, or a control supplement without DHA, from birth until around the time they were due to go home.

N3RO showed that DHA supplementation did not reduce the risk of chronic lung disease, but marginally increased the risk.  DHA treatment also did not alter the incidence of any of the other common complications seen in this fragile population.

Unexpected results

Dr Carmel Collins from SAHMRI’s Healthy Mothers, Babies and Children theme, said that before the N3RO study, DHA was thought to be beneficial for very premature babies with no harmful effects. 

“This has led to increasing amounts of DHA being included in products for premature babies. Our results suggest that additional supplementation of DHA is unnecessary and reinforces the need to thoroughly test all nutritional interventions designed for babies,” Dr Collins said.

Dr Andrew McPhee, Statewide Director, Neonatal Services, South Australia, said that the results of the N3RO study are important.

“We have learned a lot and now have definitive information to help guide health professionals in their nutritional management of very premature infants,” Dr McPhee said.

“The N3RO results reinforce that we need to be careful about the amounts of all nutrients, including DHA.  More is not necessarily better.”