Tag Archives: Obesity

Giving children the best possible start – what matters most?

Child of our Time Editor Yvonne Kelly spoke to a 500-strong audience of politicians and professionals in Gothenburg recently on what matters when it comes to giving children the best possible start in life.

Yvonne was the keynote speaker at the conference hoping to identify the best strategies for making Gothenburg a more equal and socially sustainable city.

Yvonne, Professor of Lifecourse Epidemiology at the ESRC International Centre for Lifecourse Studies at UCL  explained which factors are most closely linked with a child’s health and well-being and presented her research findings on children’s verbal skills, behaviour, bedtimes, reading and obesity.

Putting a SPRING in the step of mums-to-be

Making sure that mums-to-be are in the best possible health is key to ensuring their baby gets the best possible start in life. But what sorts of things can help them achieve that? In this episode of the Child of our Time Podcast, Professor Hazel Inskip from the MRC Lifecourse Epidemiology Unit at the University of Southampton, talks about an ongoing trial making use of healthy conversations and Vitamin D supplements to try to improve the diet of just pregnant women.

Photo credit: Pregnant, Frank de Kleine

Better start for children

Giving children the best possible start in life is the topic of a keynote talk today by our editor Yvonne Kelly.

Yvonne will be presenting a range of new evidence from the ESRC International Centre for Lifecourse Studies  to politicians, business leaders, and other professionals and key decision makers at an event discussing how Gothenburg can be made an equal and socially sustainable city.

Yvonne will talk about the factors which are most closely linked with a child’s health and well-being and present findings on children’s verbal skills, behaviour, bedtimes, reading and obesity. She will make the case that signs of social inequalities are evident early in a child’s life and that it is important to intervene early to tackle those inequalities.

Sugar-coating the childhood obesity problem

Child obesity figures appear to be on the rise again, causing much concern after earlier signs they had levelled off.  The proportion of  10- and 11-year-olds who were obese in 2015-16 was 19.8 percent, up 0.7 percent on the year before. There was a rise of 0.2 percent among four- and five-year-olds. The announcement comes as researchers at the ESRC International Centre for Lifecourse Studies at UCL have been looking in detail at how and when children become overweight. The team has also been asking whether children who are overweight are more likely to go on to smoke and drink alcohol and if their mental health suffers as they become adolescents. Yvonne Kelly explains the research findings, and considers their implications for the Government’s recent strategy for tackling the childhood obesity epidemic.

The Government’s much-awaited and much-debated childhood obesity strategy was published in August. In the end, it was less comprehensive than had been anticipated, less draconian too. It focuses on two things – reducing sugar consumption and increasing physical activity. But will it be effective in reversing this worrying obesity trend among our children?

It’s fair to say we don’t fully understand what things influence whether, when and why a child might become overweight. Research to date has shown three distinct weight pathways for children: a healthy BMI throughout childhood; becoming overweight during childhood and being overweight/obese throughout childhood.

Previous research has also shown that the child’s mother’s weight, smoking in pregnancy, mental health and other social and economic factors have some link to childhood obesity. But the evidence is far from complete and, where a child’s own mental health is concerned, it’s not at all clear which way the association works.

To try to get a clearer picture of all these things, our research looked at the BMI paths of the participants in the Millennium Cohort Study, which has tracked the lives of nearly 20,000 children born between 2000-2002. We used data collected at birth, 9 months, age 3, 5, 7 and 11.

Once we had established who was on which BMI path, we were able to look at what factors were at play in their lives and to see whether a tendency to overweight and obesity was an indication that a child would go on to face mental health difficulties in early adolescence or start smoking and drinking.

Four pathways to obesity

The BMI data for the 17,000 children we were able to look at for our study showed four distinct groups of children. More than 80 per cent of them stayed on an average non-overweight path throughout their childhood – we call it the ‘stable’ path. There was a small group (0.6 percent) of children who were obese at age 3 but were then in the stable group by age 7. We call them the the ‘decreasing’ group. There was a ‘moderate increasing group’ (13.1 percent) where children were not overweight at age 3 but whose BMIs increased throughout childhood into the overweight (but not obese) range. Finally we had a ‘high increasing’ group of children (2.5 percent) who were obese at age 3 and whose BMIs continued to increase.

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Girls were 30 percent more likely to be in the ‘moderate increasing’ group than boys and were half as likely to be on the ‘decreasing’ path. Indian, Pakistani and Black African children were up to two times more likely to be on the ‘moderate increasing’ path whilst Pakistani, Black Caribbean and Black African children were up to three times more likely to belong to the ‘high increasing’ group.

The wealthiest children were least likely to be in the ‘moderate increasing’ BMI group and children of mums who smoked during pregnancy were up to two times as likely to belong to increasing BMI groups. Children with overweight mums were most likely to be on the moderate and high increasing paths.

Children on the moderate and high increasing paths were less likely to have regular family routines – they were more likely to skip breakfast or have non-regular bedtime schedules. Interestingly, however, no strong links emerged with some of the things more readily linked with childhood obesity such as sugary drinks and snacks, watching TV and lack of physical activity such as sports, the main focus of the newly published childhood obesity strategy.

Overweight factors

So it seems quite a large range of factors influence the likelihood of a child becoming overweight or obese over the first decade of their life. On top of this, being overweight or obese would also seem to point to a less happy and fulfilling early adolescence and a tendency to explore risky behaviours like smoking and drinking.

Although our research did not show a clear link with sugary drinks and snacks, there are nevertheless some compelling arguments for reducing the sugar intake of our children. These are not only related to problems of obesity, but to wider issues including the major issue of tooth decay and associated emergency hospital admissions. There is also increasing evidence of the ‘addictive’ nature of sugar with research suggesting that it stimulates a sort of ‘reward path’ in certain centres of the brain meaning that the more we have the more we want. It has been shown that people who reduce their sugar intake tend to crave it less.

Where sugar taxes have been introduced in other countries (Mexico, France, Denmark, South Africa amongst others), the intervention has been shown to help reduce the consumption of sugary drinks. As yet, there is no evidence that it helps reduce BMI and tackle obesity, but it’s argued it will take time for us to see an effect on whole populations.

Disadvantaged families

It is hard to predict how much impact the voluntary rather than mandatory reduction in sugar content of drinks and snacks agreed in the strategy will have. As for the sugar tax that will be introduced in two years’ time, there remain concerns that disadvantaged families more likely to purchase and consume sugary goods than their better off counterparts will be hardest hit. Policy makers will need to think hard about how any negative consequences of this might be counteracted.

Our research shows clearly that when it comes to the likelihood of a child becoming overweight or obese in the first decade of their life, there are many more influences than just sugar. Those influences are at play in families even before our children are born.

Helping pregnant women to stop smoking and maintain a healthy weight, making sure all young children have healthy eating and sleeping routines would seem to be key, together with targeted support for the ethnic and social groups identified as being most at risk.

Further information and resources

BMI development and early adolescent psychosocial well-being: UK Millennium Cohort Study is research by Yvonne Kelly, Praveetha Patalay, Scott Montgomery, and Amanda Sacker. The work, published in Pediatrics, is funded by the Economic and Social Research Council.

Media coverage

Photo credit: Kim Stromstad

BMI development and early adolescent psychosocial well-being

Research looking at how and when children become overweight is helping to shed new light on ongoing efforts by the Government and others to tackle the childhood obesity epidemic.

A team of researchers at the ESRC International Centre for Lifecourse Studies at UCL has also been asking whether children who are overweight are more likely to go on to smoke and drink alcohol and if their mental health suffers as they become adolescents.

The research, published in Pediatrics, shows clearly that when it comes to the likelihood of a child becoming overweight or obese in the first decade of their life, there are many more influences than just sugar (a main plank in the Government’s Childhood Obesity Strategy).

The research also shows that  influences are at play in families even before children are born and indicates that helping pregnant women to stop smoking and maintain a healthy weight, making sure all young children have healthy eating and sleeping routines may be key, together with targeted support for ethnic and social groups identified as being most at risk.

Lead researcher, Yvonne Kelly presented the findings at the Society for Longitudinal and Life Course Studies 2016 conference in Bamberg.

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.

Photo credit: Afla

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

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.

Why poorer children are at greater risk of obesity

Obesity may be the biggest public health crisis facing the UK today. Levels have risen more than three fold since 1980. Being obese makes you vulnerable to a range of health risks. Being an overweight child makes it more likely you will become an obese adult. And you are much more likely to be an overweight child, if you come from a poor family. If current trends continue, half the population of Britain could be obese by 2050. Early intervention is the most effective way to break this cycle. And that requires a better understanding of why children become overweight. A new study by a team at the ESRC funded International Centre for Lifecourse Studies in Society and Health at UCL and LSE makes clear the scale of the problem and points to some crucial factors likely to lead less-well-off children to gain excess weight, as co-author Professor Yvonne Kelly explains.

A link between poverty and childhood obesity has been found in many developed countries. Intuitively, it seems likely this link is the result of poorer parents not being able to afford healthier food, like fruit, or outings involving exercise for their children. It could also be that those parents know less about healthy lifestyles and that they themselves eat less healthily and exercise less. But intuition is an insufficient basis for the scale of intervention required. This study is the first attempt to examine and compare in detail why children in poorer families are more likely to be overweight.

Our data comes from the Millennium Cohort Study (MCS). This tracks nearly 20,000 families from across the UK. We used measurements made when the children were aged 5 (when just entering primary school) and 11 (the point at which they leave primary school and are on the cusp of adolescence). We used standard definitions for ‘obese’ and ‘overweight’.

‘Stark’ link between poverty and obesity

The first thing we found was that the link between relative poverty and childhood obesity is stark. At age 5, poor children were almost twice as likely to be obese compared with their better off peers (6.6% of children from families in the poorest fifth of the sample were obese while the figure for the richest fifth is just 3.5%). By the age of 11, the gap has widened- nearly tripling (7.9% of the poorest fifth are obese; for the best-off, the figure is 2.9%).

Given that obesity is linked to the development of numerous chronic diseases and that there is evidence overweight and obese children are less likely to grow into economically and socially successful adults, this is a significant burden to be borne by the children of the less-well-off. And unless we can weaken the link our chances of reversing the overall obesity trend are much reduced.

Potential causes of that link

The MCS collects a broad range of data, allowing us to dig beneath these headline numbers to identify some of the specific ways in which relative poverty in childhood leads to an increased risk of obesity.

To measure the degree to which the mother followed a healthy life-style we looked at factors previously shown to be linked to the increased risk of obesity, such as whether the mother smoked during pregnancy, how long she breastfed for and whether the child was introduced to solid food before the age of four months.

We could also factor in the degree to which the mother was herself overweight or obese. To assess the impact of physical behaviour, we compared the frequency of sport or exercise, active play with a parent, hours spent watching TV or playing on a computer, journeys by bike and the time that children went to bed. We compared dietary habits via data on whether the child skipped breakfast and on fruit and sweet drink consumption.

Multiple factors

What we found was that a lot of these factors were relevant. Maternal behaviour in early childhood was certainly important. Markers of ‘unhealthy’ lifestyle here could mean as much as a 20% additional risk of obesity for a child. Measures of physical activity and diet were also relevant at both 5 and 11 years of age, as were early bedtimes and fewer hours in front of the TV or games console. Skipping breakfast and eating more fruit were factors at 5 but less significant at 11. Doing sport more frequently played a more important and protective role at age 11 than at age 5.

Further examination of the differences between the children aged 5 and aged 11 revealed that poorer children aged 5 were much more likely to gain excess weight up to age 11 than richer children. The earlier certain lifestyle factors can be challenged, therefore, the greater the chance of positive impact.

Multiple responses

Assuming that income inequality is not going to disappear, we can only tackle ‘inherited’ obesity via the lifestyle choices that tend to go with lower incomes. Early intervention with mothers clearly has huge potential. And evidence from our work suggests that this should start before birth or even conception. It is clear, too, that campaigns to encourage family physical activity and healthier diets would help.

The Government is already trying to persuade families to eat more healthily and take more exercise. But these efforts are widely targeted and their effectiveness only broadly assessed. Our analysis has already suggested better targeting. More research should be undertaken to narrow the aim and increase effectiveness still further.

Why are poorer children at higher risk of obesity and overweight? A UK cohort study is research by Alice Goisis, Amanda Sacker and Yvonne Kelly and is published in the European Journal of Public Health.

Photo credit: Playing on the computer,  John Watson

 

 

Teenage obesity and bowel cancer risk

Bowel cancer is the third most common cancer among men worldwide, with nearly 1.4 million new diagnoses each year. Links with obesity in adulthood are fairly well established with what appears to be a rise in risk with increasing body mass index. The link is significantly stronger for men than it is for women. Much less is known about potential causes at earlier stages of life, especially adolescence, as Professor Scott Montgomery from UCL explains.

Adolescence marks the transition from childhood to adulthood and is a period of accelerated growth, especially for men. We wanted to look at whether obesity, or even just excess weight, during the teenage years increase the likelihood of colorectal cancer later in life?

Asking men diagnosed with bowel cancer what they weighed as teenagers is not a reliable source of data. What we needed to examine this question robustly was a large sample of men who were accurately measured in their youth and are now sufficiently old for a significant number to have developed bowel cancer.

One such group is men who experienced compulsory Swedish military conscription assessments. Around a quarter of a million young men aged around 18 years were assessed for conscription between 1969 and 1976. After excluding those with errors in the original measurements and excluding men with pre-existing medical conditions gave us a sample of just under 240,000 – equivalent to 8 and half million person years of data.

The men’s height and weight was measured by trained personnel during the conscription examination. From these data body mass index (BMI) or kg/m² was calculated and those numbers were put into five groups – underweight (BMI of less than 18.5), normal (BMI of 18.5 to 24.9), lower overweight (BMI of 25 to 27.4), upper overweight (BMI of 27.5 to 29.9) and obese (BMI of over 30).

A blood test was also taken and tested for signs of higher levels of inflammation, which can signal diseases processes relevant to bowel cancer risk.

Cancer diagnosis

Over an average of 35 years following conscription, 885 of the men were diagnosed with bowel cancer, comprising 501 cases of colon cancer and 384 cases of rectal cancer.

Men who had been underweight in adolescence had a slightly lower risk of a colorectal cancer diagnosis than normal weight men. Lower overweight men had a non-statistically significant higher risk, upper overweight men had a statistically significant 2.08-fold higher risk and obese men had a 2.38-fold higher risk.

Men, who had suffered high levels of late adolescent inflammation, were found to be at a 63% higher risk of being diagnosed with bowel cancer than those with normal levels. The link between BMI and a diagnosis was independent of inflammation levels, suggesting adolescent BMI may be operating in a different way and through mechanisms other than the inflammation detected during adolescence.

The average age at the end of follow-up was 53.9 years, so our analysis did not look at any changes in late adulthood. It seems unlikely, though, that the upper weight groups would suffer less in later years.

It was also impossible to account for whole life measures of BMI and inflammation and so we are not able to comment on whether the strong association between adolescent BMI and bowel cancer could be mitigated by weight loss during adulthood. It is, however, plausible that it is the total duration of exposure to high BMI or inflammation that brings the increased risk rather than exposure at a specific age. High BMI or inflammatory processes already present during adolescence may persist for many years into adulthood.

It is also important to stress that the findings do not necessarily apply equally to women. Certainly, other studies have shown the associations between BMI and inflammation and bowel cancer are weaker among women than men.

Robust study

All that said, this is a robust, important study based on good quality measurement and a lengthy time frame. At a time when increasing adolescent obesity in the United States, for instance, appears to be being followed by an increasing incidence of bowel cancer among young adults, it contributes to the case for further work to be undertaken with some urgency.

What our research does suggest is a graded association between adolescent inflammation and bowel cancer and an even stronger association between adolescent BMI and the risk of bowel cancer in men. We have notable evidence of a link between these exposures at a particularly vulnerable stage of development and the later incidence of bowel cancer.

More work needs to be done, particularly to clarify how inflammation and BMI act or interact to affect an increased risk of bowel cancer. Further research is also needed to disentangle these factors from other risks both in adolescence and later life.

Further information

Adolescent body mass index and erythrocyte sedimentation rate in relation to colorectal cancer risk is research by Elizabeth D Kantor, Ruzan Udumayan, Lisa B Signorello, Edward L Giovannucci, Scott Montgomery and Katja Fall and is published in the journal, Gut.

Photo credit: Marina Lobanova