1. Impact of poor nutrition on child development and educational attainment
Dr Michelle McKinley (R.Nutr Public Health)
Senior Lecturer, Centre for Public Health
School of Medicine, Dentistry & Biomedical Science

2. Presentation structure
Impact of poor nutrition in early life
Effect of nutrition interventions on learning & performance of school age children
Breakfast
Sugar
Fish oils
Multivitamins/minerals
School food interventions
Conclusion

3. Impact of poor nutrition

4. Why is good nutrition in early life so important?
Optimal growth
Optimal cognitive development
Optimal health
Prevention of chronic disease in later life

5. The first 9 months can shape the rest of your life…….
Critical periods before and during pregnancy when specific nutrients are needed for optimal development.
Risks of a number of chronic diseases in adulthood such as hypertension, diabetes, heart disease may have their origins before birth.

6. Promoting optimal health through the lifecourse

7. Critical and sensitive periods of growth & development
Critical periods – relatively short window of time when the body is vulnerable to adverse environmental exposures such as under-nutrition – significant and lasting effect on health e.g. folate and neural tube defects
Sensitive developmental stages – broader window of time when social and cognitive skills, habits, coping strategies, attitudes and values are more easily acquired than at later ages, e.g:
Language is acquired more readily during first 10 years of life
Can be acquired at a later age but not with same level of proficiency

8. Possible in-utero effect of sub-optimal iodine status
Low maternal iodine status was associated with an increased risk of suboptimum scores for verbal IQ at age 8 years, and reading accuracy, comprehension and reading score at age 9 years
Results suggested a worsening trend in cognitive outcome with decreasing maternal status
Possible in-utero effect of sub-optimal iodine status
2013;382:331-37

9. Brain development
Diet provides the building blocks and fuel for the brain
Very rapid brain growth in last trimester of pregnancy and first 2 years of life
Malnutrition in the first year of life has a lasting effect on both behaviour and cognition
Motor skills and language develop more slowly
Intelligence scores and school performance are poorer
Early malnutrition associated with higher incidence of aggressive behaviour when children aged 9-15 years
Further peaks of brain growth have been found at 7, 12 and 15 years of age

10. Impact of poor nutrition in early life
Vitamin / mineral deficiencies
Growth stunting
Impaired cognitive development
Childhood obesity
Childhood type 2 diabetes

11. Impact of poor nutrition in early life
Vitamin / mineral deficiencies
Growth stunting
Impaired cognitive development
Childhood obesity
Childhood type 2 diabetes

12. Diet of UK schoolchildren
Most children in the UK are consuming:
too much saturated fat, sugar and salt
too little fibre and fruit and vegetables - ~ 80-90% of children aged yrs in the UK are not meeting the 5-a- day recommendation
Few meeting oily fish recommendation
Micronutrients of concern – Iron, zinc, magnesium, iodine, vitamin D
Energy imbalance

13. Global Prevalence of Overweight in Boys Prior to 1990
< 5 %
5-9.9% % % % %
≥30%
Self Reported data
© International Association for the Study of Obesity

14. Global Prevalence of Overweight in Boys 1990-1999
< 5 %
5-9.9% % % % %
≥30%
Self Reported data
© International Association for the Study of Obesity, London 2010

15. Global Prevalence of Overweight in Boys 2000-2008
< 5 %
5-9.9% % % % %
≥30%
Self Reported data
© International Association for the Study of Obesity, London 2010

16. Global Prevalence of Overweight in Girls Prior to 1990
< 5 %
5-9.9% % % % %
≥30%
Self Reported data
© International Association for the Study of Obesity, London 2010

17. Global Prevalence of Overweight in Girls 1990-1999
< 5 %
5-9.9% % % % %
≥30%
Self Reported data
© International Association for the Study of Obesity, London 2010

18. Global Prevalence of Overweight in Girls 2000-2008
< 5 %
5-9.9% % % % %
≥30%
Self Reported data
© International Association for the Study of Obesity, London 2010

19. Social disparities in childhood obesity
Source:

20. US Childhood Obesity Campaign

21. Childhood obesity in UK & Ireland
UK and Ireland - about 1 in 3 children are considered overweight or obese by the time they finish primary school
By % of boys and 70% of girls could be overweight/ obese

22. Safefood Campaign

24. Childhood diabetes in the UK
Type 2 diabetes in UK children: an emerging problem
Etishham et al. Diabetic Medicine 2000; 17:
The first cases of type 2 diabetes in children in UK - overweight girls 9-16y of Indian, Pakastani or Arabic origin

25. Example of a life-course approach framework
Childhood obesity prevention: a life-course framework.
Pérez-Escamilla and Kac, International Journal of Obesity 2013.

26. Example of a life-course approach framework
Childhood obesity prevention: a life-course framework.
Pérez-Escamilla and Kac, International Journal of Obesity 2013.

27. Effect of nutrition interventions on learning and performance of school age children

29. Inclusion criteria: Controlled trials, age range 4-18 years

30. Geographical spread
n = 16
n = 1
n = 6

31. Age range and duration
Two thirds of the studies were carried out in primary age children
Over half - short duration (<1 month)

32. Vitamin/Mineral supplements
Type of intervention
Breakfast
N=15
N=6
Sugar
N=5
Fish oil
Vitamin/Mineral supplements
N=2

33. Breakfast
Young people are more likely to skip breakfast than any other meal
Breakfast skipping increases with age
Girls at secondary school highest at-risk group for skipping breakfast
(Hoyland et al, Nutrition Bulletin)
Children who eat breakfast are more likely to meet daily nutrient intake guidelines compared with children who eat breakfast infrequently or skip breakfast

34. Breakfast Ells et al, Br J Nutr 2008
15 studies examined the effect of breakfast
10 identified an association between breakfast provision and some small cognitive and behavioural improvements
5 studies found no effect
Variable design:
Breakfast clubs;
Breakfast vs fasting;
Low- vs high-energy breakfast;
Low- vs high-protein breakfast;
Habitual breakfast vs standardised breakfast

35. Key findings
Breakfast consumption is more beneficial than skipping breakfast
More apparent in children with compromised nutritional status
Studies of school breakfast programs suggest they can have positive effect on academic performance

36. Breakfast Adolphus, Lawton, Dye 2013 Frontiers in Human Neuroscience
36 studies examined effect of breakfast on in-class behaviour & academic performance in children and adolescents
21 studies provided suggestive evidence that:
Habitual breakfast and school breakfast programs (SBP) have a positive effect on children’s academic performance
Most consistent effects observed for maths performance, most pronounced in undernourished children
11/19 studies reported positive effects on classroom behaviour e.g. less ‘off-task’ and ‘out of seat’ behaviour
But - there can be unintended consequences of SBP.....

37. Sugar studies Ells et al, Br J Nutr 2008
6 studies examined the effect of short term exposure to sugar intake
Sucrose vs aspartame or aspartame + saccharin
RCT cross-over design
Primary school aged children (n=5)
Children with symptoms of ADHD (n=5)
Sugar intake had no clinically significant adverse effects on learning or behavioural outcomes
Difficult to derive any conclusive outcome - small number of studies & the populations examined

38. Fish oil studies Ells et al, Br J Nutr 2008
5 studies examined the effect of fish oil supplementation
Randomised placebo controlled trial design
Population aged 5-13 years with symptoms of neurodevelopmental disorders (dyspraxia and ADHD)
Very different in design – fatty acid composition, dose, duration, population studied, cognitive tests used
Overall - the findings were mixed and therefore effect on learning and behaviour inconclusive

39. Vitamin/Mineral studies Ells et al, Br J Nutr 2008
2 studies examined the effect of vitamin/mineral supplementation
1 showed a significant positive effect on IQ in a small subsample
1 found no effect
These two studies alone provided insufficient evidence to formulate any conclusion

40. Recent evidence – Vitamins & Minerals
Frensham et al, Nutr Rev Influences of micronutrient and omega-3 fatty acid supplementation on cognition, learning and behaviour:
Children in developed countries may perform better on tests of nonverbal intelligence and behavioural measures after receiving vitamin and mineral supplements compared with placebo
Strongest effects in trials over 3 months and sub-groups of children (low socioeconomic status, symptoms ADHD and/ or learning disabilities)

41. School food and learning behaviour in primary schools Golley et al
School food and learning behaviour in primary schools Golley et al. Eur J Clin Nutr 2010;64:
Six primary schools in Sheffield: 4 intervention, 2 control; 12 week study; years 3,4 and 5; n=146
Food interventions – new menus, taster sessions, themed weeks, healthy eating workshops
Dining environment – changing layout and Q system; redecorating; buying new furniture, artwork and murals
Classroom behaviours observed in the hour after lunch at baseline and 12 weeks – ‘on-task’ and ‘off- task’ behavours

42. School food and learning behaviour
Pupils in intervention schools 3.4 times more likely to be ‘on-task’ in teacher-pupil interactions compared with control schools
BUT pupils in intervention schools were 2.3 times more likely to be ‘off-task’ in pupil-pupil interactions than control schools
Conclusion - intervention had positive impact on alertness
‘if this raised alertness is not appropriately channelled and supervised it may result in increased off-task behaviour when pupils are asked to work together’

43. N=156
N=156
“....+ve effect on engagement and concentration and their ability to learn in the classroom after lunch..also suggests pupils less likely to be disengaged”
Storey et al. A randomized controlled trial of the effect of school food and dining room modifications on classroom behaviour in secondary school children. Eur J Clin Nutr 2011;65:32-8.

44. Conclusion

45. Conclusion
The importance of good nutrition in early life for optimal growth and development is irrefutable
There is increasing evidence that nutrition interventions in school age children can have a positive effect on cognitive function, learning and classroom behaviour
Need for further research and robust evaluations to guide future practice
Whole school approach to nutrition – can provide an environment that encourages positive attitudes to food and healthful behaviours among students