Download Impact of poor nutrition in early life

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
[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-aday recommendation
• Few meeting oily fish recommendation
• Micronutrients of concern – Iron, zinc, magnesium,
iodine, vitamin D
• Energy imbalance
Global Prevalence of Overweight in Boys
Prior 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 Boys
1990-1999
% 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 Boys
2000-2008
% 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 Girls
Prior 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 Girls
1990-1999
% 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 Girls
2000-2008
% 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
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
Childhood obesity prevention: a life-course framework.
Pérez-Escamilla and Kac, International Journal of Obesity 2013.
Effect of nutrition interventions on
learning and performance of school age
children
Inclusion criteria: Controlled trials, age range 4-18 years
Geographical spread
n=1
n=1
n=1
n=6
n = 16
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
Sugar
N=15
N=6
Fish oil
Vitamin/Mineral
supplements
N=5
N=2
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
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
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
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.....
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
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
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
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 ‘offtask’ 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
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.
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