Girls growing up – questions of early puberty

The early onset of puberty in girls has been linked with better bone health in older women, but it is also associated with a host of negative outcomes including teenage pregnancy and serious ill health in mid-life. With girls over the last few decades starting their periods earlier and earlier, this is a real cause for concern. A better understanding is needed of who is affected and how if this trend is to be reversed and the long-term health of girls and women is to be secured. Researchers at the ESRC International Centre for Lifecourse Studies at UCL have investigated whether a girl’s socioeconomic background or ethnicity are associated with early puberty and have looked in detail at more commonly supposed links with weight and stress. Yvonne Kelly explains more.

Sexual activity whilst still young, teenage pregnancy, mental health problems, heart disease and breast cancer later in life are just some of the things linked to early puberty in girls. Over the last few decades, girls have started their periods much earlier with the average age falling from puberty has age falling to 12.9 years in 2015.

This research is the first to look over time at whether and how a girl’s social and economic circumstances and her ethnicity might be linked to the early onset of puberty. We suspected that any link that did emerge would, most likely, be explained away by other factors such as being overweight or suffering from stress.

Using information on 5,839 girls from the Millennium Cohort Study, which has been tracking the lives of nearly 20,000 children born at or around the start of the century, it was possible to know, at age 11 whether they had started their period or not.

Details of their birth weight, ethnicity, family income when they were aged 5 and height and weight when they were 7 were also available. This rich information gathered across 11 years of the girls’ lives really enabled us to put together a detailed picture over time of how these factors come together to influence the early onset of puberty.

The girls’ mothers completed questionnaires any social or emotional problems their daughter might be facing, and their own mental health.

Puberty facts and figures

Nearly one in ten of the girls, a total of 550, had started their period at age 11, with girls from the poorest families twice as likely as their most well-off peers to have done so (14.1 per cent v 6.8 per cent). Those from the second poorest group were also nearly twice as likely to have started their period.

Indian, Bangladeshi and Black African girls were most likely to have started their period at age 11, with Indian girls three and a half times more likely than their White counterparts to have done so.

Other factors

On average, girls who were heavier at age 7 and suffered stress in early childhood were more likely to have begun menstruating. Those who had started their periods early also tended to have mothers with higher stress levels, were from single parent families, and tended to have had some social and emotional difficulties themselves.

However, even when we took all these things into account, girls from the poorest and second poorest groups were still one and a half times more likely to have started their periods early.

As far as ethnicity was concerned, income, excess body weight and stress accounted for part or all of the differences in most cases. Interestingly, though with most Indian girls coming from more advantaged backgrounds than their White peers, the likelihood of them having started their period was not explained after we took all the above factors into account.

Lived experiences

Our findings highlight the different lived experiences of ethnic minority groups in the UK: for example Indians are relatively advantaged whereas Pakistanis tend to be materially disadvantaged, Bangladeshis and Black Africans are materially and psychosocially disadvantaged and have a tendency to be overweight compared with the majority ethnic group. They also demonstrate the complex and potentially opposing factors at play for the onset of puberty.

All that considered, we can say with considerable confidence that socioeconomic and ethnic disparities are indeed apparent in the UK. Given the short and long term implications for early puberty on women’s health and well being, improving our understanding of these underlying processes could help identify opportunities for interventions with benefits right across the lifecourse, not just for the girls in our study, but for future generations.

It was also encouraging to note that in the decade or so covered by the data we used, there appears to have been no further decline in the average age that girls begin puberty.

Early puberty in 11-year-old girls: Millennium Cohort Study findings is research by Yvonne Kelly, Afshin Zilanawala, Amanda Sacker, Robert Hiatt andRussell Viner and is published in Archives of Disease in Childhood.

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Young drinkers: using evidence to prevent alcohol abuse

Research by Child of our Time Editor Yvonne Kelly on 11 year-old drinking has caught the eye of Mentor, a charity working to build resilience among young people to prevent alcohol and drug misuse. The charity’s CEO, Michael O’Toole is now looking to collaborate with Yvonne in future research that will take a look a first look at data from the Millennium Cohort Study in the Autumn. In this episode of the Child of our Time podcast, Michael explains what Mentor is doing, why research based evidence is so important to the charity and how he hopes it will help prevent alcohol abuse among young children in the future.

Photo credit: Joseph Choi

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Alcohol – who is drinking or drunk age 11?

Child of our Time editor, Professor Yvonne Kelly was among a group of experts looking at drinking behaviour across the life course this week. She presented her recent thought-provoking work on 11 year-olds and drinking at a seminar for policy makers and third sector workers on alcohol and health, organised by the ESRC International Centre for Lifecourse Studies at UCL.

The talk shared findings from her research on 11 year-olds in the Millennium Cohort Study who had ever drunk alcohol or been drunk. It also explored links with a range of family and social factors including other risky behaviours such as smoking and truancy.

Listen to her talk and see her slides.

Drunkenness and heavy drinking among 11 year olds – Findings from the UK Millennium Cohort Study is research by Yvonne Kelly, Annie Britton, Noriko Cable, Amanda Sacker and Richard G. Watt

What influences 11-year-olds to drink? Findings from the Millennium Cohort Study is research by Yvonne Kelly, Alice Goisis, Amanda Sacker, Noriko Cable, Richard G Watt and Annie Britton and is published in BMC Public Health.

Mixed race kids: happier than we might think!

It’s been said and shown over the last few decades that mixed race and mixed ethnicity children tend not to do as well socially and emotionally as their non mixed peers. But new research casts a rather different light on the matter, showing that children both in the UK and US who are from mixed backgrounds are actually doing rather better. James Nazroo from the University of Manchester has been looking at the issue with colleagues at the ESRC International Centre for Lifecourse Studies, UCL and discusses his surprising findings in our latest podcast episode.

Socioemotional wellbeing among mixed race/ethnicity children in the UK and US: Patterns and underlying mechanisms is due to be published in the Journal of Health and Social Behaviour. It is part of a wider programme of ESRC funded research led by Child of Our Time editor, Yvonne Kelly at ICLS.

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Being drunk – aged 11

Better understanding why very young people start drinking has been a recent focus for the team at the ESRC International Centre for Lifecourse Studies at UCL. Research published earlier this year by the team showed that one in seven 11 year-olds said they had drunk alcohol and indicated strong ties with having friends who drank and also mums who drank. Now the researchers, led by Yvonne Kelly, have taken the work a step further to see which 11 year-olds are binge drinking or getting drunk. The work will be presented next month at an event for those interested in the links between alcohol and health.

Young people who drink heavily do worse at school, are more likely to engage in other risky behaviours such as smoking and taking drugs and die earlier than their non drinking peers. That’s been shown. But when we talk about young people, we are mostly referring to people in their late teens and early 20s.

There has been little research looking at drinking among very young adolescents, nor has much been done to look at what factors influence heavy drinking in our children and young people.

Closing the evidence gap

Our work using the Millennium Cohort Study has gone some way to closing that gap in the evidence we need to help us gain a clearer picture of just who is drinking alcohol at a very young age and what might be behind that.

Having looked at how widespread the problem might be, how family and friends fit into the picture and how 11 year-olds perceive the risks, we wanted to dig a little more deeply and focus more closely on the group of children who are binge drinking and getting drunk.

With a study as large as the Millennium Cohort Study, we have detailed information on more than 11,000 children. This means we can look at the individual and family factors connected to the issue in a meaningful and robust way.

It was reassuring to find that only 1.2 per cent (around 120) of 11 year-olds in the study reported having been drunk, with 0.6 per cent (60) of them saying they had drunk 5 or more alcoholic drinks in a single episode.

Many would argue though, that, given the serious health consequences associated with drinking at a young age, the fact that one in every hundred of UK 11 year-olds has been drunk at some point is still a matter of considerable concern.

Who is drunk at 11?

So who amongst our 11 year-old children is getting drunk? Our analysis showed that boys were twice as likely as girls to report being drunk, as were children with social and emotional problems. Truanting children were six times more likely and smokers 15 times more likely to report heavy drinking.

Interesting to us was the fact that neither mum’s nor dad’s drinking seemed to have any influence here. This was interesting in its own right, but also because our earlier research showed quite a strong link between 11 year-olds who drank any alcohol at all and mums who drank moderately or heavily. Heavy drinking was, however, reported by children who said they did not have a close relationship with their mum.

A link that did stay strong as we dug further into this question of who drinks heavily and gets drunk, was that with friends who drank. In other words, children who had friends who drank alcohol were 5 times more likely to get drunk themselves than those children who did not have drinking friends.

Perception of risk

The children we looked at were considerably less likely to get drunk if they believed strongly that drinking 1-2 alcoholic drinks each day could be harmful. So, a heightened perception of the potential harms of drinking alcohol were key here.

Our findings seem to mirror those of a recent school-based survey of 11-13 year olds in the UK, which reported 0.4 per cent had binge drunk. They also seem to point to the fact that heavy drinking in this age group is most likely to occur in peer group settings.

As the Millennium Cohort Study continues to track these children in years to come, we will gain an even clearer understanding of the consequences of heavy drinking at such a young age.

For all those concerned with the health and wellbeing of children today and in the future, there are some pointers here about areas for focus in tackling the problem including helping children understand the potential harms and empowering them to say no to alcohol regardless of any putative benefits they or their friends might perceive.

Request an invitation to the Alcohol and Health policy seminar which takes place on June 21, 2016.

Photo credit: Thom Sanders

Born in Bradford

Born in Bradford is a fascinating child health development project following the lives of thousands of children in the city. It hopes to find out more about the causes of childhood illness by studying children from all cultures and backgrounds as their lives unfold.

In this Child of our Time Podcast episode, one of the project’s lead researchers, Professor Kate Pickett from the University of York, explains more about the study, what’s in it that researchers can use, what it’s found so far and what we can expect to come out of it in the future.

Photo credit: Tim Green

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A bedtime story

Reading is key to giving children the best possible start in life. That’s what Child of our Time Editor Professor Yvonne Kelly will be telling representatives of the Swedish Government and European Commission today when she delivers the key note presentation at a seminar highlighting the importance and benefits of early interventions in children’s lives.

The seminar in Brussels has been organised by the City of Gothenburg in Sweden as part of its efforts to achieve the political goal of becoming an equal city and of its commitment to reduce inequalities.

Yvonne will be sharing research by herself and colleagues at the ESRC International Centre for Lifecourse Studies looking at factors associated with children’s poor verbal skills and behaviour problems. The research shows the links between regular bedtimes and reading with children and better outcomes for them in terms of behaviour and how well they get on at school.

Organisers of the event hope their efforts will encourage other cities in Europe to join them in their ambition to create health equality and a good start in life for all.

Photo credit: Lars Plougmann

Who are the 11 year old drinkers?

The number of young people who say they drink alcohol has recently fallen. But the teenage years are still the time most of us start drinking. Drinking can be linked to other types of risky adolescent behaviour and, later in life, alcohol remains a major risk factor for illnesses such as heart attacks, cancer and diabetes. Most research to date has focused on the later teenage years, but a new study published in BMC Public Health has taken a close look at children in early adolescence. Professor Yvonne Kelly at the ESRC International Centre for Lifecourse Studies at UCL examines the circumstances in which children first explore alcohol and what this can tell public health professionals keen to counter the most damaging effects.

The Department of Health guidelines are clear; children aged 16 or less should not drink alcohol. But they do and many parents fear absolute prohibition will lead to secret drinking and a loss of trust in the relationship. It would appear to be common sense, too, that a child drinking a small amount of watered-down wine with a family meal would be likely to develop quite different later adolescent behaviours to a child swigging vodka with friends in a bus shelter. Common sense it might be, but there has been little robust research around this.

The broad aim of our research was to examine influences on the emergence of exploratory drinking at the start of adolescence. We focused on two specific questions:

Are parents’ and friends’ drinking important influences on drinking among 11 year-olds?
What is the role of perceptions of risk, expectancies towards alcohol, parental supervision and family relationships on the likelihood of 11 year-olds drinking?

We made use of the detailed and rich data available in the Millennium Cohort Study (MCS), which has followed the lives of nearly 20,000 children born between 2000-2002.

Drinking habits

At age 11, just under 14% of MCS children said they drank alcohol. Based on their own reported drinking frequency, parents were grouped into three categories: non-drinkers, light to moderate drinkers and heavy or binge drinkers. Around 20% of mums and 15% of dads were non-drinkers. Around 60% of mums and dads were light or moderate drinkers. About a quarter of dads and just over a fifth of mums were heavy or binge drinkers. When asked whether their friends drank, 78% of MCS children said “no”.

The children were also asked about other risky behaviours such as smoking or truanting and what they felt about their family. These factors were taken into account to enable us to focus in on the effect of parents’ or friends’ drinking.

Compared to children whose mums did not drink, children whose mums were light or moderate drinkers had a 60% increased risk of drinking at 11, while those whose mums were heavy or binge drinkers had an 80% increased risk. A father’s drinking appeared to have about half as much impact, regardless of whether he was a light to moderate or heavy/binge drinker. Children who said their friends drank were more than four times as likely to drink themselves as those children with friends who didn’t drink.

Home life and perceptions of alcohol

When we looked at home life, predictably those children who reported being happy were less likely to drink than those who reported frequent family battles. Where there were low levels of parental supervision combined with a dad who drank heavily, the risk of the child drinking was, again, higher.

A child’s view about the harms of alcohol also seemed to be an important factor. The more dangerous a child thought alcohol to be, the less likely they were to drink. Children who did not see drinking alcohol as a risky activity and who also had a heavy drinking mum were much more likely to be drinking alcohol at 11.

It is not possible to make statements regarding cause and effect with this sort of study, but the numbers do show us a strong association between 11 year-olds drinking and their friends’ and mothers’ behaviour. Family relationships, perceptions of risk and expectations regarding alcohol are important, too, as are some more general characteristics of the family unit.

So, what does this tell us about the risks of drinking at 11 and how to counter those risks? The fact that likely causes of early drinking are multiple, means that counter measures need, similarly, to be aimed at a number of different aspects of a child’s life. One size will not fit all.

Advice, information and guidance

Children certainly need to have a better understanding of the risks involved in drinking. Schools and parents are clearly well placed to provide the best advice, information and guidance to children of this age, but these robust new findings can play an important role in helping to shape the focus of those discussions.

Whilst the vast majority of children at the age of eleven are yet to explore alcohol, investigating in more detail the context in which children drink – who they drink with, where, when, what they drink and how they acquire alcohol – could help inform effective policy and alcohol harm prevention strategies to mitigate the risk associated with drinking as a young person.

Public health policy should take all these factors into account, driving measures that would address parents and peer groups, popular perceptions, marketing and advertising, pricing, availability and the enforcement of age restrictions.

Further information

Read the press release and access contact details if you are a member of the media
Listen to Yvonne’s talk on the research at a recent ICLS Policy Seminar
Find out about forthcoming ICLS Policy seminar on Tuesday, 21 June 2016, focusing on what evidence longitudinal/lifecourse studies can bring to the current debate on “safe” drinking levels and what drives people to start, stop or cut back on drinking. Email icls@ucl.ac.uk for more information and to be added to the mailing list.

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Giving children a better start

Child of our Time Editor, Yvonne Kelly will today be discussing why poorer children are more likely to be obese than their better off peers at a Big Lottery Fund event looking at how to give young children a better start in life.

She will be sharing recent research from the team at the ESRC International Centre for Lifecourse Studies at UCL looking at patterns of obesity in young children using data from the Millennium Cohort Study.

The research finds that children from poorer backgrounds are the most likely to be obese and that the inequalities between richer and poorer children increase over time (between the ages of 5 and 11).

The research also identifies a number of other important factors associated with childhood obesity including smoking during pregnancy, mother’s obesity, skipping breakfast and irregular bedtimes.

The event, A Better Start ‘Focus on Diet and Nutrition is part of a programme of evaluation of the Lottery Funded ‘A Better Start’ initiative which aims to improve the life chances of babies and very young children by delivering a significant increase in the use of preventative approaches in pregnancy and first three years of life.

Yvonne is one of a group of experts and innovators in the field of child health and development to be invited to participate in the first of the initiative’s Learning and Development events. Other speakers include Eustace de Sousa, the lead for children, young people and families at Public Health England and Michael Hallsworth, director for Health at the Government’s Behavioural Insights Team, Chris Cuthbert, Director of the Big Lottery Development Fund and Celia Supiah, CEO of the charity Parents 1st.

Download Yvonne’s slides
Read a blog post from Yvonne about the research
Read the research published in the European Journal of Public Health
Listen to a podcast with Yvonne’s colleague, Professor Amanda Sacker talking about adolescents and obesity.
Photo credit: National Assembly for Wales

Changing behaviour and mixed ethnicity

The number of mixed ethnicity children born in the UK is growing. Research to date has shown that coming from a mixed ethnicity as opposed to a non mixed background has no impact on the likelihood of a child having behaviour problems. But a new report from a team at the ESRC International Centre for Lifecourse Studies at UCL and just published in the Archives of Disease in Childhood journal, tells a different story, as its lead author Afshin Zilanawala explains.

It’s known that children from an ethnic minority background in the UK tend to have poorer health and to be disadvantaged in a range of other ways, but there has been hardly any research on children of mixed ethnicity, particularly when it comes to looking at their behaviour.

What little research has been done has been constrained by a lack of data and the need to look at broad or ‘catch-all’ ethnic groups in order to have sufficient numbers to examine.

Behaviour problems and poor outcomes

Given that children’s behaviour problems have been linked to poor academic achievement and lower levels of wellbeing in adult life, it’s important to try to get to grips with the sorts of things that might influence that early behaviour.

One study that looked at mixed ethnic differences in the behaviour problems of 3 year-olds found no link. A London study looking at mixed Black Caribbean/White 11-13 year-olds found no differences between them and their White peers.

Both studies looked at the children at a point in time, so there was no chance to look at any changes in behaviour over time. But our research shows something quite different.

Using the Millennium Cohort Study, we were able to look at a group of more than 16,000 children’s behaviour from when they were 3 through till when they had turned 11 years-old.

A range of questions about peer problems, challenging behaviour, hyperactivity and emotional problems were answered by the main respondent (usually the child’s mother) and from those responses, we were able to create an overall score (TDS) to represent the level of behavioural problems the child exhibited.

Mixed ethnicity and behaviour

Interestingly, at age 3, most mixed ethnicity children had fewer problem behaviours compared with their non mixed counterparts. White mixed, Indian mixed, Pakistani mixed and Bangladeshi mixed had fewer problems than their non mixed peers.

There was no difference, however, between mixed Black Caribbean children and their non mixed counterparts and the differences for Black African mixed and non mixed children were very small.

White mixed, Pakistani mixed, and Bangladeshi mixed children experienced increases in problem behaviours compared with their non-mixed counterparts, notably after age 7.

By age 11, White mixed, Indian mixed and Black African mixed children had fewer problems than non mixed, but Pakistani mixed, Bangladeshi mixed and Black Caribbean mixed children have more problems than children from a non mixed background.

Identity crisis as children get older?

What do we make of all this? As our mixed ethnicity children get older, is there some sort of identity crisis, both social and personal that is triggering a change in behavior? The behavior problems of the mixed 11 year-old children in our study could reflect children’s struggle to reconcile their families’ heritage and culture and their personal identity formation.

As children spend more time in school, they are less influenced by their home environments and have more interactions with peers and friends, all of which could be playing a role in the behavioral difficulties some mixed ethnicity children are experiencing.

The fact that mixed relationships are more common among Black Caribbeans compared with Pakistanis and Bangladeshis could explain why there are no behaviour differences between Black Caribbean mixed and non mixed children, whilst differences do exist between the mixed and non mixed South Asian groups.

In other words, it could be that there is less strain and anxiety in mixed partnerships when those types of interethnic relationships are more common.

It would be interesting to dig further into all of this by taking into consideration school, psychosocial and socio-demographic factors, all of which could be at play here.

Mixed ethnicity and behavioural problems in the Millennium Cohort Study is research by Afshin Zilanawala, Amanda Sacker and Yvonne Kelly. It is published in Archives of Childhood Disease.

Photo credit: forest child, Philippe Put