A new study has suggested that vulnerable premature babies would benefit from earlier milk feeds.
The University of Oxford study found that babies were not at a higher risk of severe bowel problems if moved off tube-feeds early, as was feared.
400 babies, born at least five weeks early and small for their age, were studied for the Pediatrics paper.
The premature baby charity Bliss said it hoped the findings would lead to a change in feeding practices.
High-risk premature babies are vulnerable to severe bowel problems, including a condition called necrotising enterocolitis (NEC). Concerns over this risk has led to special care units previously tending to delay the start of milk feeds.
But tube feeding can also cause complications, including liver problems.
The researchers behind this study, which was funded by the charity Action Medical Research, wanted to examine if underweight premature babies could take milk earlier, which would then help them gain a healthy weight sooner.
The study was co-ordinated by the National Perinatal Epidemiology Unit at the University of Oxford, and carried out at 54 hospitals across UK and Ireland.
Almost half of the babies in the trial needed some help with their breathing, although really sick babies were not included.
Half of the babies were introduced to milk feeds on day two of life, while the remainder were given milk on day six.
Three quarters were given their mother's breast milk, rather than donor milk or formula.
"Earlier discharge home not only frees up cot space but also means that the whole family can benefit as the emotional and financial stresses will be reduced," the BBC quoted Jane Abbott, fro Bliss, as saying.
Full feeding - defined as babies successfully taking milk feeds for 72 hours - was achieved earlier in the babies who started milk feeds on day two.
On an average, babies who started milk feeds on day two of life were being fully milk fed by 18 days of age - compared with an average of 21 days of age in those who started on day six.
And the early milk feed group spent an average of 11 days in high-dependency cots, compared with 15 for the later group.
Crucially, there was no statistically significant difference in the number of babies experiencing severe bowel problems, including NEC.
In the group given early feeds, 36 (18 percent developed NEC, compared with 30 (15 percent of those who started later.
The authors of the paper, led by Alison Leaf and Peter Brocklehurst conclude that babies "would generally benefit from starting milk feeds within the first 24-48 hours after birth".
"These babies are a challenge to feed. Good nutrition and growth is very important, however their body organs, including the bowel, are immature," Leaf said.