Kindly find the below suggested reasons for favoring the use of lipids over carbohydrates and especially for premature infants:-
1- lipids typically provide energy in an amount of 2.6 times that of dextrose. Therefore providing energy from carbohydrates instead of lipids will cause an overwhelmig carbohydrate load. Here we come to your concern.
2- Dextrose = CO2, many premature infants already have ARDS! (Theoretically thinking)
3- Dextrose higher than 18 gm/kg tends to shift the metabolic process to lipogenesis.
4- Lipid intake is needed to prevent essential fatty acid deficiency.