All food is brain food when your brain is making 250,000 new neurones every minute.
In a small two-center trial first published in 2013 50 very preterm babies were randomized to different parenteral nutritional intakes. The main differences between the groups were that the controls started at 2 g/kg/d of protein, compared to 3.5 in the intervention group. The controls started at 0.5 g/kg/d of lipid given as ClinOleic, the intervention group started at 2 of SMOFLipid; both gradually increased to a max of 3.4. One they were receiving 110 mL/kg/d of milk the fortification was different between the groups, with the enhanced group getting an extra 0.8 g/kg/d of protein, to achieve 4.4 g/kg/d, and getting extra omega 3 fatty acids to arrive at a total of 166 kcal/kg/d, compared to 146. (which is a whole lot of calories!)
Unfortunately the planned sample size was not achieved, the study was stopped early because there was more sepsis in the enhanced nutrition group (p<0.04). Stopping a trial for a barely significant difference between groups is really not a good idea, but it is often a difficult decision, especially when the difference is an important adverse outcome. The primary outcome was post-natal growth restriction. The authors were following a number of secondary outcomes as were the data monitoring committee. The risk that one of those outcomes will be ‘statistically significant’ at some point during the data accumulation is enormous. That is why stopping rules should be much more stringent than that. Of course if you continue the study and it turns out that there really is more sepsis at the end of the study, you may then be criticized, and you might feel bad. You might indeed face totally ridiculous criticisms similar to those that were directed at the SUPPORT trial by Public Citizen, who don’t understand how interim analyses work.
Having said that the authors published a second paper with the growth data; because of the small sample size there was a difference in the birth growth variables between groups, which actually favoured the controls, more SGA babies in the enhanced nutrition group. Despite this there were significant advantages of the enhanced protocol. None of the non-growth restricted babies in the intervention group became growth restricted, compared to 1/3 of the babies in the control group. The z-scores for weight dropped by about 0.3 for the intervention group, between birth and 30 days of age, and by about 0.7 in the controls. Head growth was also better.
A subset of the infants had MRI performed at term, which has just been published, and which is why I am writing this post. Strømmen K, Blakstad EW, Moltu SJ, Almaas AN, Westerberg AC, Amlien IK, et al. Enhanced Nutrient Supply to Very Low Birth Weight Infants is Associated with Improved White Matter Maturation and Head Growth. Neonatology. 2015;107(1):68-75. (yes its the first article of 2015 on the blog). There were differences between the groups. Which is about as much as I can say about head MRI, the mean diffusivity was lower in the intervention group. Which is good, apparently. In just about every region of the brain there were significant differences in what I shall from now on refer to as MD, as if I knew what I was talking about.
So give more food. It makes the babies grow better, including their head, and it improves their MD, which is a good thing to do.
I have to query whether the benefit is more food or different food! The intervention group got SMOF, which includes Fish Oil, rich in omega 3’s, the control group got Clinoleic, which is low omega 3. From the data provided I don’t see any way to distinguish between the potential impact of more calories vs more omega 3.
You could well be right, using an enhanced diet with more protein, more calories and more omega-3s makes it impossible to know which part of that diet had the effect.