The preliminary data from the Oxford University DOLAB study first used epidemiological data to assess a possible link between blood omega-3 status, behaviour, and sleep quality.
Speaking at the Food And Behaviour Research (FAB Research) symposium held in London yesterday to discuss the wider findings and implications of the DOLAB study, Professor Paul Montgomery from the University of Oxford revealed new preliminary data from the study that links omega-3 status to sleep quality and disorders in children.
The DOLAB research project involved both wider population data to look for associations in addition to RCT data on supplementation outcomes. Findings from both arms of the study have shown that omega-3 - and particularly docosahexaenoic acid (DHA) - is associated with sleep quality in children, said the expert.
Montgomery explained that the findings from the epidemiological arm of the study revealed decreased sleep quality and an increased risk of sleep disorders was well correlated with blood levels of the omega-3 long chain fatty acid DHA.
"This was highly significant," said Montgomery, adding that it was 'striking' just how many children in the study had been found to have clinical signs of sleep disorders, and that blood levels of DHA were significantly correlated with sleep scores.
Further findings from the smaller-scale RCT data found that supplementation with the DHA increased measures of sleep quality from baseline significantly, Montgomery added.
There were slight, but non- significant, changes in sleep patterns for the placebo group in the randomised trial, he confirmed.
"We have got far less waking during the night. We've got more sleeping, and more efficient sleeping as the ratio of time in bed to time asleep is significantly improved," explained the Oxford expert.
"These are not small changes. These are substantial changes," he commented. "I think clinically they are very significant changes too."
In the initial epidemiological study the team used validated parental surveys of sleep quality perception, and analysed these scores against blood measures of omega-3.
"We ended up with a sample of 395 where we had both child sleep health questionnaire data and blood data," said Montgomery. "This is a large number for any study of this kind."
In addition to linking omega-3 status to sleep quality and risk of having sleep problems, the team also noted that their findings also confirmed previous research that has linked sleep disorders to behavioural problems.
"As sleep problems increased, so did behavioural problems," revealed Montgomery.
"We know that sleep is very important for behaviour. It's been demonstrated in a large number of trials. But what has not been shown [until now] is what fatty acids might have to do with it," he added.
The team then used a 15% sub-sample of these children in a more detailed randomised trial to assess whether supplementation with DHA helped to improve measures of sleep.
Children involved in the RCT were asked to wear actigraphs - wrist watch style sensors that measure sleep - for around five days at the baseline of the trial and again after supplementation with either the omega-3 or placebo.
Montgomery revealed that supplementation with the algal DHA used in the trial had significant effects on raising blood levels of omega-3 and on sleep quality.
"Importantly, they were awake for less [throughout the night]. They were asleep for 46 minutes more," said Montgomery. "These kids were sleeping a lot more [after supplementation]."
"The action is clear," he commented. "I'm struck by the size and the scale of this."
However, the Oxford expert also conceded that findings are still preliminary:
"This is all post-hoc, subgroup analysis. So it's all very exploratory," he commented. "I am the first to admit that this is a relatively small sample [for the RCT], but it ties in ell with the subjective results from parents which are from a much larger sample."