Impact of poor nutrition on child development and educational attainment Dr Michelle McKinley (R.Nutr Public Health) Senior Lecturer, Centre for Public.

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 [email protected]

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

Impact of poor nutrition

Why is good nutrition in early life so important?

• Optimal growth

• Optimal cognitive development

• Optimal health

• Prevention of chronic disease in later life

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.

Promoting optimal health through the lifecourse

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

• 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

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

Impact of poor nutrition in early life

• Vitamin / mineral deficiencies

• Growth stunting

• Impaired cognitive development

• Childhood obesity

• Childhood type 2 diabetes

Impact of poor nutrition in early life

• Vitamin / mineral deficiencies

• Growth stunting

• Impaired cognitive development

• Childhood obesity

• Childhood type 2 diabetes

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 11-18 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

Global Prevalence of Overweight in BoysPrior to 1990

% Overweight

< 5 %

5-9.9%

10-14.9%

15-19.9%

20-24.9%

25-29.9%

≥30%

Self Reported data

© International Association for the Study of Obesity

Global Prevalence of Overweight in Boys1990-1999

% Overweight

< 5 %

5-9.9%

10-14.9%

15-19.9%

20-24.9%

25-29.9%

≥30%

Self Reported data

© International Association for the Study of Obesity, London 2010

Global Prevalence of Overweight in Boys2000-2008

% Overweight

< 5 %

5-9.9%

10-14.9%

15-19.9%

20-24.9%

25-29.9%

≥30%

Self Reported data

© International Association for the Study of Obesity, London 2010

Global Prevalence of Overweight in GirlsPrior to 1990

% Overweight

< 5 %

5-9.9%

10-14.9%

15-19.9%

20-24.9%

25-29.9%

≥30%

Self Reported data

© International Association for the Study of Obesity, London 2010

Global Prevalence of Overweight in Girls1990-1999

% Overweight

< 5 %

5-9.9%

10-14.9%

15-19.9%

20-24.9%

25-29.9%

≥30%

Self Reported data

© International Association for the Study of Obesity, London 2010

Global Prevalence of Overweight in Girls2000-2008

% Overweight

< 5 %

5-9.9%

10-14.9%

15-19.9%

20-24.9%

25-29.9%

≥30%

Self Reported data

© International Association for the Study of Obesity, London 2010

Social disparities in childhood obesity

Source: www.oecd.org

US Childhood Obesity Campaign

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 2050 - 55% of boys and 70% of girls could be overweight/ obese

Safefood Campaign

http://www.safefood.eu/Childhood-Obesity

Childhood diabetes in the UK

Type 2 diabetes in UK children: an emerging problem Etishham et al. Diabetic Medicine 2000; 17: 867-871

The first cases of type 2 diabetes in children in UK - overweight girls 9-16y of Indian, Pakastani or Arabic origin

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

Example of a life-course approach framework

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

Example of a life-course approach framework

Effect of nutrition interventions on learning and performance of school age

children

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

Geographical spread

n = 16

n = 1

n = 1

n = 6

n = 1

n = 1

n = 1

n = 1

n = 1

Age range and duration

•Two thirds of the studies were carried out in primary age children

•Over half - short duration (<1 month)

Type of intervention

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, 2012. 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

BreakfastElls 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

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

BreakfastAdolphus, 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.....

Sugar studiesElls 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

Fish oil studiesElls 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

Vitamin/Mineral studiesElls 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

Recent evidence – Vitamins & Minerals

• Frensham et al, Nutr Rev 2012. 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)

School food and learning behaviour in primary schools

Golley et al. Eur J Clin Nutr 2010;64:1280-8.

• 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

www.childrensfoodtrust.org.uk

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’

www.childrensfoodtrust.org.uk

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.

“....+ve effect on engagement and concentration and their ability to learn in the classroom after lunch..also suggests pupils less likely to be disengaged”

N=156N=156

Conclusion

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