New Study on Obesity and Mental Health

2 May, 2019

By Imogen Buxton-Pickles

On Sunday 28th April, the BBC reported on a large UK study which suggests that obese seven-year-olds are at greater risk of suffering emotional problems, such as anxiety and low mood, when they reach 11.

The article said that the researchers from Liverpool University found obesity and mental health were closely linked, and gradually increased throughout childhood. It also found that girls tended to have higher BMIs and more emotional problems than boys.

The question that came to my mind straight away was, ‘Great, but we also know that activity drops off at this age; what’s the relationship there?’ and then I thought, ‘So what should be expected of schools?’.

The researchers analysed information on more than 17,000 children born in the UK between 2000 and 2002, using statistical modelling to measure the link between obesity and emotional problems. 

They had information on children's height and weight (BMI) as well as reports on their emotional problems, provided by their parents, at ages three, five, seven, 11 and 14 years old.

From the age of seven, the study found obesity and emotional problems were closely linked.

But the link wasn't apparent in younger children.

'Not as simple as eating less'

In the article, Dr Charlotte Hardman, senior psychology lecturer at the University of Liverpool, said the findings showed obesity and emotional problems were likely to develop hand-in-hand in childhood.

She said it was already known that obesity and mental health problems were interlinked in adulthood, and the same could be true in childhood.

From the age of seven, mental health and obesity appear to be entwined and
exacerbate each other.

Dr Hardman said that meant children "being stuck in vicious cycles".

As both rates of obesity and emotional problems in childhood are increasing,
understanding their co-occurrence is an important public health concern, as both are
linked with poor health in adulthood

What about activity?

It’s widely known that regular activity increases the level of hormones such as Serotonin, which enhances mood, and Noradrenaline and Dopamine which improves motivation, focus and learning.

But our children are becoming less and less active as they get older. The Millennium Cohort Study 2 showed us that less than half of 7-year olds are active enough, with girls (38%) less likely to achieve the guidelines than boys (63%). It’s interesting to see the link here as well between girls’ lack activity and mental wellbeing! By the time they’re 11, 2.5% did more than the recommended guidelines 3 .

Is the true issue that we should also look at activity levels? Is it all a vicious cycle where one impacts the other continuously?

What can schools do about it?

It is evident that inactivity, obesity and poor mental health may all be intertwined but what can schools do about it?

On obesity; schools can teach children about what they should or shouldn’t eat and deliver healthy school meals, but so much is out of the school’s hands when they leave.

On mental wellbeing; there are many great resources on mindfulness and other techniques to support the child.

One thing a school can do simply and effectively is get their children more active.  The NHS Chief Medical Officer already asks for more than 30 minutes of structured activity at school every day for every child and the new Ofsted inspection criteria is likely to ask whether a child receives the opportunity for a healthy, active lifestyle. 

So, for any school that worries about what it should do on mental wellbeing and obesity; I would say get the children active! It supports mental wellbeing naturally and can encourage support children to be more confident, thereby possibly breaking the link between obesity and mental wellbeing.

For schools to be serious about mental wellbeing – they need to get moving!


  1. The study is published in JAMA Psychiatry.
  2. Griffiths et al, ‘How active are our children? Findings from the millennium cohort study’, BMJ Open 2013
  3. National Institute for healthcare excellence (2009) ‘Promoting physical activity for children and young people’.