Premature babies' risk of obesity from nutrition supplements low

The parents of babies born preterm or small-for-dates in New Zealand can feel some reassurance that giving their babies nutritional supplements appears to have little adverse effect after early childhood.

About 15 million babies are born prematurely (at less than 37 weeks gestation) in the world each year and the rates are climbing in most countries. In New Zealand, around 7.4 percent of babies are born preterm. Preterm and small-for-dates babies may develop slower and as adults have an increased risk of obesity, diabetes and heart disease.

To maintain normal growth and development, preterm and small-for-dates babies are often given supplements to bring their weight up. These include milk fortifier and enriched formula. Previously a series of observational studies indicated that faster growth in early life might  lead to childhood obesity which in turn posed health risks in later life.

However researchers from the Liggins Institute, have completed a systematic review of 42 randomised controlled trials, the gold standard of research, involving 4,352 preterm and small-for-dates babies. They found that nutritional supplements did not affect their body mass index in childhood, though the weight and length of toddlers did increase. However none of the increases continued after early childhood.

Team member PhD student Luling Lin said that the review suggested that parents of preterm and small-for-dates babies need not be concerned that supplements would lead to later overweight or obesity. She cautioned that the data was limited, highlighting the need for more research in this area. The research paper by Luling Lin, Emma Amissah, Greg Gamble, Caroline Crowther and Jane Harding was published in PLOS Medicine this week.