N05070: A systematic review of the effect of nutrition, diet and dietary change on learning, education and performance of children of relevance to UK schools

Study Duration: November 2005 to April 2006

Contractor: University of Teesside

Concerns persist about nutrition imbalances and inequalities and their impact on the performance, behaviour, attendance and motivation of UK schoolchildren. A range of epidemiological data show that low intakes or poor nutritional status is associated with poor development (including a range of cognition and performance outcomes) in early childhood.

This type of data should be interpreted with caution, as impaired school performance and cognition is also associated with socioeconomic deprivation factors that may independently affect development, such as limited stimulation at home. The evidence is also difficult to interpret and generalise because of cultural and methodological differences.

There are also a small number of intervention studies that have assessed the affect of dietary improvement on school performance. Few of these interventions appear to have been assessed with any rigour and therefore the reliability of these requires assessment.

The systematic review to gauge the strength of the evidence in the area will be conducted in two stages.

Stage 1: Develop protocol

Stage 1 will involve:

• Scoping exercise of the types of nutrients and diets (such as breakfast, fish oils, B vitamins, fruit and vegetables) and outcomes (such as performance and learning gains) of interest to inform the search strategy.
• Scoping various commercially available electronic databases and other sources of information that could potentially be searched, for their relevance to this work.
• Development of the protocol for the systematic review outlining the search strategy, the databases that will be searched and the inclusion criteria for the studies.

Stage 2: Conduct systematic review

Stage 2 will involve:

• Running the search strategy developed in stage 1, which will be systematic and comprehensive.
• Citations (hits) from each database will then be searched against the inclusion and exclusion criteria.
• Included studies will undergo key word mapping, to produce a systematic map of empirical research. The key wording tool will be based on the two-page instrument used by the Evidence for Policy and Practice Information and Co-ordinating Centre (EPPI centre).
• Quantitative and qualitative data will be extracted from each of the studies selected for in-depth review, using the data extraction tool, which will resemble that used by EPPI.

In total, 69 studies were identified from the review, of which 29 were controlled trials and these were taken forward for in-depth review:

• 15 studies examined the effect of breakfast
• six studies examined the effect of short-term sugar intake with Attention Deficit Hyperactivity Disorder Symptoms
• five studies examined the effect of fish oil supplementation in a population aged 5-13 years with symptoms of learning/behavioural disorders
• two studies examined the effect of vitamin/mineral supplementation
• one study investigated good nutrition in the first year of school

Six of these studies originated from the UK (three breakfast, two fish oil and one vitamin/mineral supplementation).

The majority of the studies included in the review were carried out in primary school children and took place over a short duration (less tha one month). Many studies lacked quality in research methodology and reporting and failed to account for other factors which may affect performance/learning/education, such as habitual dietary intake, physical activity levels, locality and family environment.

The report concludes that due to the small number of studies, the great variation in study designs and the lack of quality in many of the studies, it is impossible to reach any firm conclusions as to the effect of diet on learning, education and performance in school aged children in developed countries.

The authors note that further studies are needed, particularly in the UK, which must be of high quality, representative of all populations, undertaken for longer duration and use universal standardised measure of educational attainment.

The final report is available from the Agency's Information Centre.
To obtain a copy, please contact the Enquiry Desk, Information Services, Food Standards Agency (tel: 020 7276 8181/8182 or email: infocentre@foodstandards.gsi.gov.uk)

Contact: For any enquiries concerning this research project, please contact the relevant Programme contact or email: science@foodstandards.gsi.gov.uk