̽��ֱ�� of Cambridge - Centre for Diet and Activity Research (CEDAR)

Just over half of six-year-olds in Britain meet physical activity guidelines

cjb250 — Thu, 11 Aug 2022 16:00:54 +0000

Physical activity is beneficial for our physical and mental health, but activity levels tend to decrease across childhood and adolescence. Current UK physical activity guidelines recommend that children and young people from ages 5 to 18 years do an average of 60 minutes of moderate-to-vigorous physical activity (such as playing in the park or physical education) per day across the week. For all children, it is also recommended that they keep to a minimum extended periods of sedentary behaviour (such as sitting watching TV).

To investigate how much activity children do in their early primary school years, researchers from the Medical Research Council (MRC) Epidemiology Unit at the ̽��ֱ�� of Cambridge and the MRC Lifecourse Epidemiology Centre at the ̽��ֱ�� of Southampton provided 712 six-year-olds with Actiheart accelerometers, which measured their heart rate and movement. ̽��ֱ��children, who had been recruited as part of the ongoing Southampton Women’s Survey, wore these continually for an average of six days.

̽��ֱ��results of the study are published today in the Journal of Physical Activity & Health.

At age six, children were sedentary for a daily average of more than five hours (316 minutes) and engaged in over 7.5 hours (457 minutes) of low-level physical activity and just over an hour (65 minutes) of moderate-to-vigorous physical activity.

Just over half of the children (53%) met the current UK recommended guidelines, with boys being more likely to reach the target than girls (63% of boys vs 42% of girls).

Dr Esther van Sluijs from the MRC Epidemiology Unit at Cambridge said: “Using accelerometers, we were able to get a much better idea of how active children were and we found that just over a half of six-year-olds were getting the recommended amount of physical activity. But this means that almost half of British children in this age group are not regularly active, which we know is important for their wellbeing and their performance at school.”

When the researchers analysed activity levels by time of day, they found that girls engaged in less moderate-to-vigorous physical activity during the school day at age six. Possible explanations are that girls wear skirts, which may make physical activity more challenging, or that they choose less active options during break times.

̽��ֱ��researchers were able to look at longitudinal data from some children – that is, data recorded over a period of time rather than just a snapshot – and found that compared to at age four, at age six children became more sedentary (on average, around 30 minutes per day more compared to when they were four), but also engaged in an additional seven minutes per day of moderate-to-vigorous physical activity.

Dr Kathryn Hesketh from the MRC Epidemiology Unit at Cambridge added: “This is something of a double-edged sword: children appear to do more moderate-to-vigorous physical activity when they start formal schooling, which is really positive, but they also spend more time sedentary. This may in part be because of the structure of the school day, so we may want to look at ways to reduce sedentary time when children are younger, to prevent that behaviour becoming habitual.”

Professor Keith Godfrey from the ̽��ֱ�� of Southampton commented: “These analyses indicate that new initiatives to promote physical activity must consider the lower activity levels in girls and at weekends. ̽��ֱ��time when children transition into formal schooling is an important opportunity to ensure a much higher proportion achieve recommended levels of activity.”

While based on detailed data collected up to 2012, evidence from national questionnaire based surveys is that children's patterns of activity levels changed little in the years leading up to the COVID-19 pandemic, with widely recognised even lower rates of meeting the Chief Medical Officer guidelines during the pandemic.

̽��ֱ��work was largely supported by Wellcome and the Medical Research Council.

Reference
Hesketh, KR et al. Activity behaviours in British 6-year-olds: cross-sectional associations and longitudinal change during the school transition. Journal of Physical Activity & Health; 11 Aug 2022; DOI: 10.1123/jpah.2021-0718

All averages quoted are mean.

Fifty-three percent of six-year-olds met the recommended daily guidelines for moderate-to-vigorous physical activity in a study carried out pre-pandemic by researchers at the universities of Cambridge and Southampton.

This is something of a double-edged sword: children appear to do more moderate-to-vigorous physical activity when they start formal schooling, which is really positive, but they also spend more time sedentary

Kathryn Hesketh

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Group of children playing tug of war

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Sugar purchased in soft drinks fell 10% following introduction of industry levy

cjb250 — Wed, 10 Mar 2021 23:30:06 +0000

Following publication of this study, subsequent analysis by the research team identified that the analysis presented in the original paper contained an error. ̽��ֱ��authors alerted the BMJ, who have now retracted the original paper and published a corrected version in BMJOpen.

Overall, the estimate of change in purchasing of sugar from all soft drinks combined at one year post implementation of the levy reduces from a 30g (or 10%) fall per household per week to an 8g (or 3%) fall per household per week. Alongside, the estimate of change in volume of soft drinks purchases increases from no change to a 189g (or 3%) increase per household per week.

̽��ֱ��authors believe that the results still have important public health implications and indicate that the UK Soft Drinks Industry Levy may have had a public health benefit (by reducing household purchasing of sugar from soft drinks) without harming, and indeed potentially benefiting, industry (by increasing total volume of soft drinks purchased).

For further details, visit: https://www.bmj.com/content/372/bmj.n254

While the volume of soft drinks purchased did not change, the amount of sugar in those drinks was 30g lower per household per week, which the researchers say represents a ‘win-win’ for public health and industry.

Sugary drinks have been linked to a number of health issues, including dental caries, obesity, type 2 diabetes and heart disease. In April 2018, the UK introduced a Soft Drinks Industry Levy explicitly designed to incentivise manufacturers to reduce the sugar content of soft drinks. ̽��ֱ��levy was placed on manufacturers, importers and bottlers rather than on consumers. It included two levy tiers: 24p per litre for ‘high tier’ drinks containing more than or equal to 8g total sugar per 100ml; and 18p per litre for ‘low tier’ drinks containing more than or equal to 5g and less than 8g total sugar per 100ml.

A team led by researchers from Cambridge’s Centre for Diet and Activity Research (CEDAR) at the MRC Epidemiology Unit analysed data from the Kantar Worldpanel, in which participating households are asked to record all food and drink purchases brought into the home. This included approximately 31 million purchases of drinks, confectionery and toiletries from March 2014 to March 2019.

̽��ֱ��team divided soft drinks into three categories based on sugar content: high tier drinks, low tier drinks and no levy drinks (those with less than 5g total sugar per 100ml). As the Soft Drinks Industry Levy may have led households to substitute other drinks, they also examined purchasing of drinks exempt from the levy, including milk-based drinks, alcoholic drinks and no-added-sugar fruit juices.

̽��ֱ��researchers compared purchases in March 2019 against a ‘counterfactual’ estimate – that is, an estimate based on pre-existing trends of how the purchases would look had the levy not taken place at all. This is the first analysis of the impact of the UK Soft Drinks Industry Levy on drink purchases that takes pre-existing trends into account. ̽��ֱ��results of the study, funded by the NIHR, are published today in ̽��ֱ��BMJ.

Prior to the introduction of the levy, the volume of high-tier drinks and amount of sugar associated was on a downward trend. However, even taking this trend into consideration, by March 2019, the volume of high tier drinks purchased had fallen by 155ml (44%) per household per week compared to the counterfactual estimate. ̽��ֱ��amount of sugar purchased in these drinks reduced by 18.0g per household per week, a 46% decrease.

For low tier drinks, the volume of drinks purchased was 177ml (86%) lower per household per week in March 2019 compared with the counterfactual estimate. ̽��ֱ��amount of sugar fell by 12.5g (an 86% decrease).

Although the volume of no levy drinks purchased didn’t change, as these soft drinks are not sugar-free and some increased in their sugar content, this meant that the sugar purchased from these drinks increased by 15.3g, equivalent to a 166% increase.

Overall, compared to the counterfactual estimate, there was no change in the volume of all soft drinks purchased in March 2019. However, there was a reduction in sugar purchased in all soft drinks (including exempt drinks) combined of 29.5g per household per week, equivalent to a 10% decrease.

̽��ֱ��introduction of the Soft Drinks Industry Levy also coincided with significant decreases in purchasing of bottled water. However, the team say this reduction may be due to increases in concern about single-use plastic, which have been attributed, in the UK, to the broadcast of the BBC’s nature documentary series Blue Planet 2.

Dr David Pell from CEDAR, the study’s first author, said: “A 10% drop in the amount of sugar purchased from soft drinks might sound modest, but we know there’s an association between the amount of sugar drinks we consume and the risk of developing conditions such as obesity, type 2 diabetes and high blood pressure. Cutting out even a relatively small amount of sugar should have important impacts on the number of people with obesity and diabetes.”

Professor Martin White, also from the CEDAR, and the project lead, added: “ ̽��ֱ��Soft Drinks Industry Levy appears to have led to a reduction in the amount of sugar that people are purchasing in soft drinks without impacting on the overall volume of soft drinks sold. It’s likely that this is due to manufacturers reformulating their products and reducing the sugar concentration in their drinks, as well as to consumers switching to lower sugar alternatives.

“This represents a valuable win-win for public health and the food industry – potentially improving people’s health with no detrimental effect on the volume of soft drinks that companies are selling.”

̽��ֱ��research was funded by the National Institute for Health Research and the Medical Research Council. ̽��ֱ��Centre for Diet and Activity Research is funded by the British Heart Foundation, Cancer Research UK, the Economic and Social Research Council, the Medical Research Council, the National Institute for Health Research, and Wellcome.

Reference
Pell, D et al. Changes in British household purchases of soft drinks associated with implementation of the Soft Drinks Industry Levy: a controlled interrupted time series analysis. BMJ; 11 Mar 2021; DOI: 10.1136/bmj.n254

̽��ֱ��amount of sugar purchased by households through soft drinks fell by 10% in the year following the introduction of the UK Soft Drinks Industry Levy, say researchers at the ̽��ֱ�� of Cambridge. [RETRACTED]

marsjo

Bottles of soft drink

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Successive governments’ approaches to obesity policies have destined them to fail, say researchers

cjb250 — Tue, 19 Jan 2021 08:52:28 +0000

This is the conclusion of new research by a team at the ̽��ֱ�� of Cambridge funded by the NIHR School for Public Health Research.

̽��ֱ��researchers say their findings may help to explain why, after nearly thirty years of government obesity policies, obesity prevalence in England has not fallen and substantial inequalities persist. According to a report by NHS Digital in May 2020, 67% of men and 60% of women live with overweight or obesity, including 26% of men and 29% of women who suffer clinical obesity. More than a quarter of children aged two to 15 years live with obesity or overweight and the gap between the least and most deprived children is growing.

Successive governments have tried to tackle the obesity problem: in research published today in ̽��ֱ��Milbank Quarterly, Dolly Theis and Martin White in the Centre for Diet and Activity Research (CEDAR) at the ̽��ֱ�� of Cambridge identified 14 government-led obesity strategies in England from 1992 to 2020. They analysed these strategies – which contained 689 wide-ranging policies – to determine whether they have been fit for purpose in terms of their strategic focus, content, basis in theory and evidence, and implementation viability.

Seven of the strategies were broad public health strategies containing obesity as well as non-obesity policies such as on tobacco smoking and food safety. ̽��ֱ��other seven contained only obesity-related policies, such as on diet and/or physical activity. Twelve of the fourteen strategies contained obesity reduction targets. However, only five of these were specific, numerical targets rather than statements such as ‘aim to reduce obesity’.

Theis said: “In almost 30 years, successive UK governments have proposed hundreds of wide-ranging policies to tackle obesity in England, but these are yet to have an impact on levels of obesity or reduce inequality. Many of these policies have largely been flawed from the outset and proposed in ways that make them difficult to implement. What’s more, there’s been a fairly consistent failure to learn from past mistakes. Governments appear more likely to publish another strategy containing the same, recycled policies than to implement policies already proposed.

“If we were to produce a report card, overall we might only give them 4 out of 10: could do much better.”

Theis and White identified seven criteria necessary for effective implementation, but found that only 8% of policies fulfilled all seven criteria, while the largest proportion of policies (29%) did not fulfil a single one of the criteria. Fewer than a quarter (24%) included a monitoring or evaluation plan, just 19% cited any supporting scientific evidence, and less than one in ten (9%) included details of likely costs or an allocated budget.

̽��ֱ��lack of such basic information as the cost of implementing policies was highlighted in a recent National Audit Office report on the UK Government’s approach to tackling childhood obesity in England, which found that the Department of Health and Social Care did not know how much central government spent tackling childhood obesity.

“No matter how well-intended and evidence-informed a policy, if it is nebulously proposed without a clear plan or targets it makes implementation difficult and it is unlikely the policy will be deemed successful,” added Theis. “One might legitimately ask, what is the purpose of proposing policies at all if they are unlikely to be implemented?”

Thirteen of the 14 strategies explicitly recognised the need to reduce health inequality, including one strategy that was fully focused on reducing inequality in health. Yet the researchers say that only 19% of policies proposed were likely to be effective in reducing inequalities because of the measures proposed.

UK governments have to date largely favoured a less interventionist approach to reducing obesity, regardless of political party, prioritising provision of information to the public in their obesity strategies, rather than more directly shaping the choices available to individuals in their living environments through regulation or taxes. ̽��ֱ��researchers say that governments may have avoided a more deterrence-based, interventionist approach for fear of being perceived as ‘nannying’ – or because they lacked knowledge about what more interventionist measures are likely to be effective.

There is, however, evidence to suggest that policymaking is changing. Even though the current UK government still favours a less interventionist approach, more recent strategies have contained some fiscal and regulatory policies, such as banning price promotions of unhealthy products, banning unhealthy food advertisements and the Soft Drinks Industry Levy. This may be because the government has come under increasing pressure and recognises that previous approaches have not been effective, that more interventionist approaches are increasingly acceptable to the public, and because evidence to support regulatory approaches is mounting.

̽��ֱ��researchers found little attempt to evaluate the strategies and build on their successes and failures. As a result, many policies proposed were similar or identical over multiple years, often with no reference to their presence in a previous strategy. Only one strategy (Saving Lives, published in 1999) commissioned a formal independent evaluation of the previous government’s strategy.

“Until recently, there seems to have been an aversion to conducting high quality, independent evaluations, perhaps because they risk demonstrating failure as well as success,” added White. “But this limits a government’s ability to learn lessons from past policies. This may be potentially compounded by the often relatively short timescales for putting together a strategy or implementing policies.

“Governments need to accompany policy proposals with information that ensures they can be successfully implemented, and with built-in evaluation plans and time frames. Important progress has been made with commissioning evaluations in the last three years. But, we also need to see policies framed in ways that make them readily implementable. We also need to see a continued move away from interventions that rely on individual’s changing their diet and activity, and towards policies that change the environments that encourage people to overeat and to be sedentary in the first place.”

Living with obesity or excess weight is associated with long-term physical, psychological and social problems. Related health problems, such as type-2 diabetes, cardiovascular disease and cancers, are estimated to cost NHS England at least £6.1 billion per year and the overall cost of obesity to wider society in England is estimated to be £27 billion per year. ̽��ֱ��COVID-19 pandemic has brought to light additional risks for people living with obesity, such as an increased risk of hospitalisation and more serious disease.

̽��ֱ��research was funded by the NIHR School for Public Health Research, with additional support by the British Heart Foundation, Cancer Research UK, Economic & Social Research Council, Medical Research Council, and Wellcome Trust.

Reference
Dolly R Z Theis, Martin White. Is obesity policy in England fit for purpose? Analysis of government strategies and policies, 1992-2020. Milbank Quarterly; 19 Jan 2021; DOI: https://doi.org/10.1111/1468-0009.12498

Government obesity policies in England over the past three decades have largely failed because of problems with implementation, lack of learning from past successes or failures, and a reliance on trying to persuade individuals to change their behaviour rather than tackling unhealthy environments.

In almost 30 years, successive UK governments have proposed hundreds of wide-ranging policies to tackle obesity in England, but these are yet to have an impact on levels of obesity or reduce inequality

Dolly Theis

Fitsum Admasu

Silhouettes of three women running

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Beyond the pandemic: rethink the menu and how much it costs

lw355 — Thu, 24 Sep 2020 08:30:12 +0000

Boris Johnson has urged the country “to lose weight to beat coronavirus” through exercise and healthy eating. Dr Jean Adams suggests that food policies should be sensitive to the fact that healthier diets are beyond the budget of too many people in the UK.

Becoming less active and gaining weight: downsides of becoming an adult

cjb250 — Mon, 20 Jan 2020 00:15:23 +0000

Many people tend to put on weight as they leave adolescence and move into adulthood, and this is the age when the levels of obesity increase the fastest. This weight gain is related to changes in diet and physical activity behaviour across the life events of early adulthood, including the move from school to further education and employment, starting new relationships and having children.

Writing in Obesity Reviews, researchers from the Centre for Diet and Activity Research (CEDAR) at Cambridge looked at changes in physical activity, diet and body weight as young adults move from education into employment and to becoming a parent. To do this, they carried out systematic reviews and meta-analyses of existing scientific literature – these approaches allow them to compare and consolidate results from a number of often-contradictory studies to reach more robust conclusions.

Leaving school

In the first of the two studies, the team looked at the evidence relating to the transition from high school into higher education or employment and how this affects body weight, diet and physical activity. In total, they found 19 studies covering ages 15-35 years, of which 17 assessed changes in physical activity, three body weight, and five diet or eating behaviours.

̽��ֱ��team found that leaving high school was associated with a decrease of seven minutes per day of moderate-to-vigorous physical activity. ̽��ֱ��decrease was larger for males than it was for females (a decrease of 16.4 minutes per day for men compared to 6.7 minutes per day for women). More detailed analysis revealed that the change is largest when people go to university, with overall levels of moderate-to-vigorous physical activity falling by 11.4 minutes per day.

Three studies reported increases in body weight on leaving high school, though there were not enough studies to provide a mean weight increase. Two studies suggested that diets decrease in quality on leaving high school and one suggested the same on leaving university.

“Children have a relatively protected environment, with healthy food and exercise encouraged within schools, but this evidence suggests that the pressures of university, employment and childcare drive changes in behaviour which are likely to be bad for long-term health,” said Dr Eleanor Winpenny from CEDAR and the MRC Epidemiology Unit at the ̽��ֱ�� of Cambridge.

“This is a really important time when people are forming healthy or unhealthy habits that will continue through adult life. If we can pinpoint the factors in our adult lives which are driving unhealthy behaviours, we can then work to change them.”

Becoming a parent

In the second study, the team looked at the impact of becoming a parent on weight, diet and physical activity.

A meta-analysis of six studies found the difference in change in body mass index (BMI) between remaining without children and becoming a parent was 17%: a woman of average height (164cm) who had no children gained around 7.5kg over five to six years, while a mother of the same height would gain an additional 1.3kg. These equate to increases in BMI of 2.8 versus 3.3.

Only one study looked at the impact of becoming a father and found no difference in change.

There was little evidence looking at physical activity and diet. Most studies including physical activity showed a greater decline in parents versus non-parents. ̽��ֱ��team found limited evidence for diet, which did not seem to differ between parents and non-parents.

“BMI increases for women over young adulthood, particularly among those becoming a mother. However, new parents could also be particularly willing to change their behaviour as it may also positively influence their children, rather than solely improve their own health,” said Dr Kirsten Corder, also from CEDAR and the MRC Epidemiology Unit.

“Interventions aimed at increasing parents’ activity levels and improving diet could have benefits all round. We need to take a look at the messages given to new parents by health practitioners as previous studies have suggested widespread confusion among new mothers about acceptable pregnancy-related weight gain.”

Reference
Winpenny, E. et al. Changes in physical activity, diet and body weight across the education and employment transitions of early adulthood: A systematic review and meta-analysis. Obesity Reviews; 20 Jan 2020

Corder, K. et al. Becoming a parent: a systematic review and meta-analysis of changes in BMI, diet and physical activity. Obesity Reviews; 20 Jan 2020

Leaving school and getting a job both lead to a drop in the amount of physical activity, while becoming a mother is linked to increased weight gain, conclude two reviews published today and led by researchers at the ̽��ֱ�� of Cambridge.

Children have a relatively protected environment, with healthy food and exercise encouraged within schools, but this evidence suggests that the pressures of university, employment and childcare drive changes in behaviour which are likely to be bad for long-term health

Eleanor Winpenny

Anupam Mahapatra

People exercising

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Menu labelling linked to less fat and salt in food at major UK restaurant chains

cjb250 — Wed, 16 Oct 2019 18:00:23 +0000

̽��ֱ��researchers behind the study argue that if government policy made menu labelling mandatory, it could encourage restaurants to produce healthier options, leading to public health benefits.

Obesity levels worldwide have almost tripled since 1975, making it one of the most pressing public health challenges today. Poor diet is a leading contributor to obesity as well as to diseases including type 2 diabetes, heart disease and cancer.

Food from restaurants and fast food takeaways tends to be high in energy, fat, sugar and salt compared to food prepared at home. Some health campaigners have called for restaurants to improve the nutritional information available to customers. Mandatory menu labelling for large restaurant chains was introduced in the US in May 2018. In the UK, the government included voluntary menu labelling in its Public Health Responsibility Deal in 2011. A proposal for compulsory menu labelling was included in last year’s Childhood Obesity Plan and a public consultation closed last December, but no announcement on a final policy has been made so far.

̽��ֱ��assumption behind such measures is that providing customers with clearer information on the energy content of food served will allow them to make more informed, and hence ‘better’, choices. But it is also possible that menu labelling could change what outlets serve, as nutritionally-poor food could lead to bad publicity.

Researchers at the Centre for Diet and Activity Research (CEDAR), ̽��ֱ�� of Cambridge, set out to determine whether there were differences in the energy and nutritional content of menu items served by popular UK chain restaurants with ,versus without, voluntary menu labelling in their stores. Their results are published today in the open access journal PLOS ONE.

̽��ֱ��team first looked at energy and nutritional information on the websites of the most popular 100 UK restaurant chains during March and April 2018. Of these 100 restaurants, 42 provided some form of energy and nutritional information online, but only 14 provided menu labelling in stores.

Items from restaurants with in-store menu labelling had on average 45% less fat and 60% less salt than items from other restaurants.

“This is the first study to look at differences in nutritional content of food from restaurants with and without menu labelling in the UK,” said Dolly Theis from CEDAR and the MRC Epidemiology Unit at Cambridge. “It suggests that on the whole, restaurants that provide information on calories on menus also serve healthier food, in terms of fat and salt levels. As well as providing useful information for customers, mandatory menu labelling could also encourage restaurants to improve the nutritional quality of their menus.”

̽��ֱ��researchers say that it is possible that menu labelling encourages restaurants to change the content of their food and also that those chains with ‘healthier’ offerings are more likely to label their menus. Twelve of the 14 restaurants that provided voluntary menu labelling were in the top 50 restaurants by sales – larger chains may come under more scrutiny from governments, the media, campaign groups and the public to provide both menu labelling and healthier options.

Across all menu categories, at least three-quarters of individual menu items were below the daily maximum recommended intake for energy, fat, saturated fat, sugar and salt. However, some individual items contained more than twice the daily recommended amount for energy, fat, saturated fat, sugar or salt. In one case, an individual dish contained 5,961Kcal – almost three times the daily recommended maximum for an average adult woman.

Dr Jean Adams added: “We found some restaurant items that hugely exceeded the daily recommended intake for energy, fats, sugar and salt. More than a quarter of UK adults eat meals out at least once a week, so such large or nutritionally-imbalanced portions could contribute to poor dietary intake at a population level.”

̽��ֱ��research was funded by the British Heart Foundation, Cancer Research UK, Economic and Social Research Council, Medical Research Council, National Institute for Health Research, and Wellcome.

Reference
Theis, DRZ and Adams, J. Differences in energy and nutritional content of menu items served by popular UK chain restaurants with versus without voluntary menu labelling: a cross-sectional study. PLOS ONE; 16 Oct 2019; DOI: 10.1371/journal.pone.0222773

Food sold at restaurants whose menus display energy information is lower in fat and salt than that of their competitors, according to new research from the ̽��ֱ�� of Cambridge.

As well as providing useful information for customers, mandatory menu labelling could also encourage restaurants to improve the nutritional quality of their menus

Dolly Theis

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Chef preparing food

Researcher profile: Dolly Theis

Tackling the obesity epidemic – and particularly childhood obesity – is likely to require policy changes at a local and national level. But how can academics feed the findings of their research into this process?

̽��ֱ��answer may not be straightforward, as PhD candidate Dolly Theis from the MRC Epidemiology Unit explains.

“Policymaking is a complex business,” she says. “Even for those inside its very heart, the policymaking process can feel like an unnavigable maze.”

Dolly has experience of working closely with policymakers and has brought this knowledge with her to Cambridge. Prior to joining the MRC unit, she led research into childhood obesity and grassroots sport at the Centre for Social Justice think tank in Westminster. Between 2010-2013, she worked as a Parliamentary Researcher for Baroness Jenkin of Kennington, focused primarily on food waste, international development, obesity, poverty and women in politics.

At Cambridge – which Dolly describes as “an inspiring and pretty magical place” – she is studying how the UK government policymaking process works in relation to childhood obesity. In particular, she wants to understand how childhood obesity policies are conceived, framed and introduced by government; what and how evidence is understood and used; and who is most influential in the policymaking process.

“My research involves me doing what feels like investigative work!” she explains. “I try to identify as much quality evidence as I can that best explains the policymaking process in relation to childhood obesity; whether that is searching for relevant documents, speaking to people, trawling government and Parliament websites, or keeping up with the news.

“Hopefully by understanding how the policymaking process works in practice, academics and researchers can better influence it with the very best research.”

Outside of work, Dolly runs the Big Tent Ideas Festival, a non-partisan political ideas festival bringing together thousands of people from all backgrounds, beliefs, sectors and parties to discuss the major problems facing our society and to find consensus on solutions.

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Children from disadvantaged backgrounds and certain ethnic minorities do less vigorous physical activity

cjb250 — Tue, 28 May 2019 08:55:20 +0000

̽��ֱ��patterns mirror inequalities seen in levels of childhood obesity, suggesting a need for a greater focus on the promotion of vigorous physical activity, particularly for those children from more disadvantaged backgrounds.

Over the past four decades, the global prevalence of childhood obesity has increased tenfold. Obesity in childhood is associated with illness and early death in adulthood, so tackling childhood obesity is increasingly a public health priority for governments.

There are also widening inequalities in obesity prevalence. By age 11, UK children from disadvantaged families are three times as likely to be obese than more advantaged children. There are also stark ethnic and racial differences in levels of childhood obesity, with higher rates of obesity within certain ethnic minorities including children from Black African, Black Caribbean, Pakistani and Bangladeshi backgrounds.

Evidence suggests that more vigorous intensity activity – such as running or swimming – is more strongly linked with reduced waist circumference and body fat than moderate intensity activity. International guidelines say that children should engage in moderate-to-vigorous intensity activity for at least 60 minutes per day.

“When we look at overall physical activity we don’t see clear differences between children from different backgrounds despite clear inequalities in obesity,” says Rebecca Love, a Gates Cambridge Scholar at the Centre for Diet and Activity Research (CEDAR) in the MRC Epidemiology Unit at the, ̽��ֱ�� of Cambridge. “To investigate this further, we looked at whether overall physical activity was hiding inequalities in the intensity with which that activity is performed that might explain these patterns.”

̽��ֱ��researchers studied data from almost 5,200 children aged 7 years who were part of the Millennium Cohort Study, a longitudinal study of children born in the UK between September 2000 and January 2002. ̽��ֱ��children were given accelerometers and their activity measured for a minimum of ten hours for three days. ̽��ֱ��results are published today in the journal BMJ Open.

̽��ֱ��team found that the higher the level of education attained by the mother, the more minutes of vigorous intensity activity her child was likely to have, accounting for time spent in moderate physical activity. Children with mothers with high levels of education accumulated three minutes more vigorous activity per day then those with low levels of education. Similarly, the team found significantly more time spent in vigorous intensity activity incrementally with increasing household income.

Intensity differences were also apparent by ethnicity. White British children perform on average more than three minutes more daily vigorous physical activity in comparison to children from Pakistani and Bangladeshi backgrounds. Children from ‘other ethnic groups’ also accumulated 2.2 minutes fewer daily vigorous intensity activity overall.

It is suggested these differences are relevant on a population level and changes to reduce differences in vigorous physical activity could have population implications for inequalities in adiposity in UK children. ̽��ֱ��differences were consistent in both boys and girls.

“There are clear differences in the amount of vigorous physical activity a child does depending on their socioeconomic and ethnic background,” explains senior author Dr Esther van Sluijs. “Although individually, these differences are small, at a population level they are likely to make a difference. Changes to reduce existing gaps in vigorous intensity activity could help reduce existing inequalities in levels of obesity in children.”

̽��ֱ��team say that there are many factors that might explain the differences, including access to or the cost of participating in sports activities, and a parent working longer, inconsistent work hours within a low-income job. There may also be differences in home and family support for physical activity between ethnic groups.

“Children from different backgrounds can face a number of barriers preventing them from participating in sports or other types of vigorous physical activity,” adds Dr Jean Adams. “We need to find more ways to provide opportunities for all children to get involved in vigorous activity.”

̽��ֱ��research was funded by the British Heart Foundation, Department of Health, Economic and Social Research Council, Medical Research Council, and Wellcome. Additional support was provided by Gates Cambridge.

Reference
Love, R et al. Socio-economic and ethnic differences in children’s vigorous intensity physical activity: a cross-sectional analysis of the UK Millennium Cohort Study. BMJ Open; 28 May 2019

Children from disadvantaged backgrounds and certain ethnic minority backgrounds, including from Pakistani and Bangladeshi backgrounds, have lower levels of vigorous physical activity, according to researchers at the ̽��ֱ�� of Cambridge.

Children from different backgrounds can face a number of barriers preventing them from participating in sports or other types of vigorous physical activity

Jean Adams

Margaret Weir

Children playing

Researcher profile: Rebecca Love

Rebecca Love, a PhD student at the Centre for Diet and Activity Research (CEDAR) researches the factors that drive obesity, particularly among children from different economic and social backgrounds.

It is perhaps ironic, then, that she has spent most of her PhD “sitting at a computer in the CEDAR offices at Addenbrooke’s [Hospital] – not quite the picturesque Cambridge working environment I had imagined”!

Rebecca grew up in Canada. As part of her undergraduate degree at Queen’s ̽��ֱ�� in Kingston, Ontario, she spent a year in Trinidad and Tobago working alongside the Caribbean Sport and Development Agency on a project to implement educational programming and change policy structures to protect the rights of children. It was through these experiences that she gained an interest in the evaluation of interventions and in understanding how to identify what works within a given context.

Rebecca is currently finishing her PhD, supported by Gates Cambridge. Her work has involved examining population cohort studies from a range of countries to understand whether differences in patterns of physical activity behaviour between children help to explain the rising and widening obesity disparities seen within many countries. She is now investigating whether school-based interventions are effective at improving physical activity behaviour – and if this effect is the same in children from advantaged and disadvantaged backgrounds and between girls and boys.

“I’m fascinated by the complexity of influences driving the worsening epidemic of obesity globally,” explains Rebecca. “If we’re going to find effective solutions, we’ll need an interdisciplinary approach involving collaboration from a wide range of stakeholders and institutions.”

Fortunately, Rebecca’s research does sometimes get her out ‘into the field’. In 2017, she visited the ̽��ֱ�� of the Witwatersrand in Johannesburg, South Africa to investigate physical activity and obesity within the Birth to Twenty Cohort. This is Africa’s largest and longest running cohort of adolescent health and development, which has followed a cohort of children born in 1990 in Soweto, South Africa.

“Two months of warmth in exchange for the UK winter and cold bike rides to Addenbrooke’s came at a welcome time in my PhD! There, I had the opportunity to visit childcare centres and schools in townships surrounding Johannesburg and Cape Town, across which rates of childhood overweight and obesity are rising. Listening and learning from the experiences and perspectives of individuals working across these settings was thought-provoking.”

Rebecca describes CEDAR as “an extremely supportive and welcoming community. ̽��ֱ��opportunity to constantly be exposed to innovative research and conversations has been really influential and a central part of my learning experience”.

She is currently a PhD student at King’s College. This, together with her Gates Cambridge scholarship, has allowed her to meet students and researchers from a wide range different backgrounds and disciplines, developing friendships and learning from perspective of peers from all corners of the world.

“Constant events, lectures and opportunities make Cambridge an exciting and stimulating place to be a graduate student. It can be quite distracting at times – but to me that is one of the best parts about being here!”

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Removing sweets and crisps from supermarket checkouts linked to dramatic fall in unhealthy snack purchases

cjb250 — Tue, 18 Dec 2018 19:00:52 +0000

̽��ֱ��study, published in the journal PLOS Medicine, found that 76% fewer purchases of sugary confectionery, chocolate and potato crisps were bought and eaten ‘on-the-go’ from supermarkets with checkout food policies compared to those without. In addition, 17% fewer small packages of these items were bought and taken home from supermarkets immediately after introducing a checkout food policy.

Large supermarket chains such as Tesco, Asda and Sainsbury’s have captured the majority of the grocery market and play a major role in shaping food preferences and purchasing behaviour. Retail practices such as product displays, positioning, promotions and pricing can all influence consumers’ choices in stores.

Supermarket checkouts provide a unique location for prompting purchases as all customers have to pass through them to pay and may spend considerable time in queues; however, the majority of food at supermarket checkouts could be considered unhealthy. Over the last decade, many UK supermarket groups have made voluntary commitments to remove or limit unhealthy foods at the tills or to provide healthier options.

“Many snacks picked up at the checkout may be unplanned, impulse buys – and the options tend to be confectionery, chocolate or crisps,” says Dr Jean Adams from the Centre for Diet and Activity Research at the ̽��ֱ�� of Cambridge. “Several supermarkets have now introduced policies to remove these items from their checkouts, and we wanted to know if this had any impact on people’s purchasing choices.”

To examine the effect that the introduction of checkout food policies in major supermarket chains has had on shoppers’ purchasing habits, Dr Adams led a team of researchers at the universities of Cambridge, Stirling and Newcastle who analysed data from the Kantar Worldpanel’s Consumer panel for food, beverages and household products. Six out of the nine major supermarkets introduced checkout food policies between 2013 and 2017. ( ̽��ֱ��researchers anonymised the information to avoid ‘naming and shaming’ companies.)

Firstly, the team looked at how purchases of less healthy common checkout foods brought home changed following the implementation of checkout policies. They used data from over 30,000 UK households from 12 months before to 12 months after implementation.

̽��ֱ��researchers found that implementation of a checkout food policy was associated with an immediate 17% reduction in purchases. After a year, shoppers were still purchasing over 15% fewer of the items compared to when no policy was in place.

Next, they looked at data from 7,500 shoppers who recorded food bought and eaten ‘on-the-go’ during 2016-17 from supermarkets with and without checkout food policies. On-the-go purchases are often impulsive and can be the result of children pestering their parents. ̽��ֱ��researchers found that shoppers made 76% fewer annual purchases of less healthy common checkout foods from supermarkets with checkout food policies compared to those without.

As the study was not a randomised control trial, it was not possible to say definitely that the changes in purchasing behaviour were due to the checkout food policies. Stores that chose to have checkout food policies may have been different from those that did not. Or shoppers may have changed to purchasing larger packages from the same stores, or similar products from stores that aren’t supermarkets.

“Our findings suggest that by removing sweets and crisps from the checkout, supermarkets can have a positive influence on the types of purchases their shoppers make,” says Dr Katrine Ejlerskov, the study’s first author. “This would be a relatively simple intervention with the potential to encourage healthier eating. Many of these purchases may have been impulse buys, so if the shopper doesn’t pick up a chocolate bar at the till, it may be one less chocolate bar that they consume.”

“It may seem obvious that removing unhealthy food options from the checkout would reduce the amount that people buy, but it is evidence such as this that helps build the case for government interventions to improve unhealthy behaviours,” adds Dr Adams.

“One such intervention might be to introduce nutritional standards for checkout food as suggested in the Government’s recent Childhood Obesity Plan. Such a government-led policy might prove attractive to supermarkets as it would provide a level playing field across the sector.”

̽��ֱ��work was undertaken by the authors as part of the Public Health Research Consortium. ̽��ֱ��Public Health Research Consortium is funded by the Department of Health and Social Care Policy Research Programme.

Reference
Ejlerskov, KT et al. Supermarket policies on less healthy food at checkouts: natural experimental evaluation using interrupted time series analyses of purchases. PLOS Medicine; 18 Dec 2018; DOI: 10.1371/journal.pmed.1002712

Policies aimed at removing sweets and crisps from checkouts could lead to a dramatic reduction in the amount of unhealthy food purchased to eat ‘on-the-go’ and a significant reduction in that purchased to take home, suggests new research led by the ̽��ֱ�� of Cambridge.

It is evidence such as this that helps build the case for government interventions to improve unhealthy behaviours

Jean Adams

paulbr75 (Pixabay)

Shopping carts

Researcher Profile: Dr Jean Adams

“Most people have a vague idea about what eating better involves – more fruit and veg, less fat and sugar – and they also often have an aspiration to eat better,” says Dr Jean Adams. “But they don’t always manage to put this aspiration into practice.”

Jean’s research group in the Centre for Diet and Activity Research (CEDAR) asks why this is the case – and what can be done about it. “We’re particularly interested in how we can provide environments that make it easier for everyone to eat better. This might involve making healthier foods more available, cheaper, attractive, or easier to prepare.”

Jean began her career studying medicine at Newcastle ̽��ֱ��, but admits she “never really enjoyed it”. But between her second and third year at medical school, she did a research year and realised this was where her passion lay. She went on to study for a PhD in public health and since then her career has involved public health research, rather than clinical medicine.

“I do a lot of talking and listening to people working in local and national government to understand what sorts of opportunities they feel are coming up and what research they would find helpful. In Cambridge we then try and focus on what the most rigorous and useful research we could do would be.”

Jean hopes that her research will lead to more people finding it easier to eat better. “Poor diet accounts for as much death and disease in the UK as tobacco smoking, so we are trying to address a major problem,” she says.

While she finds her work interesting and rewarding, she says research can be more prosaic than it is sometimes painted. “I have never had a Eureka moment and no-one’s ever slapped a sheaf of papers on my desk that explains everything! In my experience, research is more about grinding things out with a lot of refining and polishing leading to incremental accumulation of knowledge.”

Nor is it particularly glamorous: “ ̽��ֱ��CEDAR offices are in a slightly dingy corner deep in the heart of Addenbrooke’s Hospital. We have a small meeting room with a big white board. Sometimes I think that whiteboard has been the key vehicle for almost all of the great research CEDAR has produced!”

But fortunately, it can be both enjoyable and exhilarating. “My favourite meetings are the ones where we talk about ideas and share our brain power to arrive at new insights. I particularly enjoy when someone makes me see an old problem in a new way, or helps me crystallise some vague ideas that have been bubbling in my head for a while.

“We also try not to take ourselves too seriously and have a lot of fun along the way.”

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