Tag Archives: BMI

Out of work and overweight: Think again.

There’s a widely held preconception that people who are out of work are overweight, perpetuated by the media and, indeed, reinforced by some academic studies. But recent robust evidence throws a whole new light on things and indicates that unemployed people are in fact much more likely to be underweight, and less likely to be overweight, than their peers who have not recently been unemployed. Amanda Hughes from the Institute for Social and Economic Research explains how she came to question narratives about benefit claimants being lazy and overweight and go on to undertake research she believes provides a more accurate picture.

While I was doing my PhD, I volunteered at a foodbank, and noticed that there were more people coming in who were painfully thin than too heavy. Some had not eaten that day or the day before. Others had walked for two hours to get there, because paying for a return bus journey was out of the question.

Of course, not all people who are out of work turn to food banks, and not all people who turn to foodbanks are unemployed. But that experience got me thinking: have researchers and public health officials been so concerned with obesity that they have missed a crucial part of the story? If weight loss or weight gain can occur during unemployment depending on personal circumstances, might there be an overlooked ‘U-shaped’ association of unemployment and body weight, with excess obesity and excess underweight among jobseekers?

We know that risk of dying is higher for jobseekers than for employed peers, and it is often assumed that increased overweight and obesity among jobseekers plays a role. But studies on the relationship of unemployment and body weight have been inconclusive; some document weight gain with unemployment, but others suggest weight loss. However, previous studies have compared only average effects – average change in body weight following job loss, or average differences between unemployed people and controls, and may have missed a more complicated ‘U-shaped’ association.

Working age BMI

Using Understanding Society, a longitudinal, nationally representative survey of more than 40,000 UK households, my colleague Meena Kumari and I were able to look at the BMI (body mass index) of 10,737 working-age adults between 2010 and 2012.

What was different about our study, was that we did not assume unemployment would impact BMI in the same direction for everyone. Rather, we allowed for a simultaneously raised risk among jobseekers of both underweight and obesity, by comparing the probabilities of being underweight, overweight, and obese between current jobseekers, recent jobseekers, and people who had not been unemployed since the start of the survey (the control group). To isolate the impact of unemployment itself, we took into account other factors such as demographics, chronic health conditions and mental health, smoking and physical activity.

A small proportion (0.7 per cent) of the people in our study who were employed were classed as underweight (i.e. had a BMI below 18.5). But for those in our sample who were unemployed, the proportion shot up to almost 4 per cent. This pattern remained when we took into account factors such as their education, gender, smoking, overall health, physical activity and alcohol consumption.

Certain groups were especially at risk: there were more extreme effects for longer-term unemployed people, for men, and people from lower-income households, suggesting household reserves or the support of family members may act as a sort of buffer against weight-loss effects. At the same time, currently unemployed people were much less likely to be overweight than peers who had not recently been unemployed (29 per cent v 40 per cent).

We did find that unemployed people were more likely to be obese, perhaps suggesting changes in dietary quality following unemployment towards energy-dense but nutrient-poor foods. However, this was only the case for non-smokers, which might reflect competing priorities between tobacco, food and other essentials for smokers on severely restricted budgets.

Quantitative evidence

Together, these results point to a complex picture in which jobseekers, depending on the complexities of individual lives, are at increased risk of both underweight and obesity, each with their own associated health risks.

The elevated underweight and reduced overweight among current jobseekers are quantitative evidence that many unemployed people are not eating enough in simple caloric terms. Despite the political importance of this question, evidence of this effect has so far been fairly anecdotal.

Our results make an important contribution to research trying to explain the increased risk of chronic illness and mortality for unemployed people – suggesting that, at least in contemporary Britain, being underweight may contribute to that much more than previously realised.

At the very least, I hope our evidence will be used to challenge preconceptions and debunk myths about unemployment. It has implications for the way politicians, journalists and the wider public perceive unemployment, and for anyone concerned with the health effects of being out of work.

Unemployment, underweight and obesity: Findings from Understanding Society is research by Amanda Hughes and Meena Kumari at the Institute for Social and Economic Research at the University of Essex, and published in the journal Preventive Health.

You can also read an article about this research in The Guardian.

Photo credit: At Work in the Capital Area Foodbank Warehouse, Geoff Livingston

Want to be fit at forty? Don’t have a baby early!

Having a family early may not be good for your health later on. That was the conclusion of a team of researchers at the ESRC International centre for Lifecourse Studies when they looked at the interplay between the work and family lives of men and women, whose lives have been tracked over time in the 1958 Birth Cohort Study. But was it the same story for people born earlier and has it been the same for people who were born later? Dr Rebecca Lacey, who led the research, has been looking at the lives of thousands of adults in three Birth Cohort Studies to see whether the way their work and family lives intertwine impacts on the likelihood of them becoming overweight or obese later on.

In a recent blog for WorkLife, my colleague Anne McMunn outlined some of our research showing that, for both men and women, having children early, especially as a teenager, was closely linked with poorer health once they got into their forties.

Not only did the people we looked at for that piece of research have bigger waists, but they also had a great deal more fat circulating in their blood and less ‘good’ cholesterol, both of which are linked with a heightened risk of heart disease and diabetes.

Those findings stayed strong, even for young parents who had a job and were married, a clear indication that having children early on, with all the associated stresses and strains, seems to take a heavy toll on health over the life course.

For that piece of research, we looked only at people who had taken part in the National Child Development Study, also known as the 1958 Birth Cohort. For this research we looked, in addition at thousands more people, born in 1946 (National Survey of Health and Development) and another group born in 1970 (the British Cohort Study) whose lives had been tracked since birth.

Across cohorts

The reason for looking across cohorts was to see whether changes across generations in how we combine work and family (having children later, more cohabitation and less marriage, more women working etc.) have contributed in some way towards poorer health for some.

As with the earlier research, we made use of 12 specially created lifecourse types covering information on employment, partnerships and parenthood, such as ‘Work, Later family’ ‘Later family, Work break’, ‘Teen parent’.

Each individual in each birth cohort was ascribed a lifecourse type and this was then linked to their Body Mass Index (BMI) and how that changed over time. We went on to see how those figures differed between lifecourse types within and across the three cohorts. We used the World Health Organisation’s (WHO) definition of overweight (BMI greater than or equal to 25) and obesity (BMI greater than or equal to 30).

In addition, we took a host of other factors including our participants’ socio-economic background, prior health and educational attainment into consideration.

We anticipated that, as our earlier research had shown, that people who worked less and had children earlier would show steeper increases in BMI and that across the three cohorts, those increases would become more pronounced.

Changing attitudes and behaviours

The distribution of lifecourse types across the three cohorts reflected, as we thought it would, changing attitudes and behaviours across generations, with increasingly more women in employment and early parenthood becoming less and less common.

In the 1946 cohort, the average BMI of a very small group of men who were ‘Teen parents’ increased from 20.3 to 26.76 between age 16-42, significantly more than any other work-family combination. The same was true for male teen parents in the 1958 cohort and also for those who worked and had a family early. In the 1970 cohort, men who had no children or had children later had BMI that increased significantly less than those who became parents earlier. The only exception to this was a group of men with no family and unstable work.

Another notable finding across all three cohorts was that average BMIs for men at age 42 in all of the work-family groups were higher than the WHO threshold for overweight. The only exception was men who had children later or no children at all.

For women in the 1946 study, there was no real difference between the groups when we looked at how their BMI increased between the ages of 16 and 42. The average BMI of the 1958 cohort women who had children early increased significantly more than that of women who had them later. Women in the 1970 cohort who did not work and had children early had the biggest BMI rise (6.69) with teen parents (6.31) close behind. The average BMI of the 42 year-old women in these two groups was on the WHO obesity threshold (30), with the average BMI for the remaining work-family groups all falling under the WHO definition of overweight (25 and above).

Other interesting things to emerge included:

  • BMI increased more for male teen parents than female in the 1970 cohort
  • Marriage seems to have particular health benefits for men
  • Divorce has greater negative health effects for men than women

Negative impact

This research reinforces what we found earlier, which is that for both men and women having children early (especially in your teens) no matter what your background, is likely to have a negative impact on your health in mid life, especially if you don’t have a job or if your work is irregular or unstable. Looking across three cohorts, we can also see that those differences have become more pronounced.

How to explain and better understand how all this plays out in the day to day lives of younger parents is a challenge. Having children early may disrupt someone’s education or career. Younger parents may also be more likely to smoke and drink and exercise less than their older counterparts, unhealthy behaviours which can become established early and set in across adulthood.

Whatever the context and the reasons, there are some important messages here for young people, prospective parents, health and education professionals as well as for Government; not least that decisions about how to combine work and family life, especially when to become a parent, may have long lasting ramifications for your health.

This research adds to a growing body of evidence which makes it clear that, as far as obesity is concerned, early intervention is key and that we need to consider the complex way in which our biological and social lives intertwine over time.

Further information

Work-family life courses and BMI trajectories in three British birth cohorts is research by Rebecca Lacey, Amanda Sacker, Steven Bell, Meena Kumari, Diana Worts, Peggy McDonough, Diana Kuh, and Anne McMunn. It is published in the International Journal of Obesity.

Photo credit: Baby Fingers, Thomas

Having a baby early? It might not be good for you later

Being employed is generally good for your health. That’s what a large body of research has shown over the years. But what about when you put having a family into the mix? That’s a question that Dr Anne McMunn at the ESRC International Centre for Lifecourse Studies at UCL has been asking in a series of studies looking at the interplay between work-family life and health in middle age. Here she outlines her findings and explains why having children early may not be good for you.

When couples think about starting a family, they may make decisions around a host of concerns. Finances, careers, childcare all spring readily to mind as things that could crop up in discussions about when it might be best to have a child. Not many people will stop and think about how and when having a child might affect their health later on in life – but maybe they should.

Research to date has shown that combining paid work with family responsibilities is usually linked with better health outcomes, although existing research has a number of shortcomings: men are often excluded, health measures have tended to be self-reported rather than objective, few studies take account of the role health plays in whether or not people work, get married and have children in the first place, and, crucially, few studies look across the lifecourse at the timings of entry into parenthood.

Combining work and family life

Using the National Child Development Study, which is following the lives of 17 thousand people born in 1958, our research has looked at how they combined their work and family lives between the ages of 16 and 42 and what that meant for their health in their mid 40s.

The thinking behind the research was that those people with more stressful work-family lives (often characterised by having children very young, being unemployed, and not marrying or forming a long-term partnership) would go on to have physical signs or indicators of poor health such as high cholesterol and blood pressure, being overweight etc.

All the men and women in the study were ascribed one of 12 lifecourse types e.g. ‘Work, Later family’, ‘Later family, Work break’, ‘Teen parent’.

Table 1-1

Almost all men were in a group characterised by long-term full-time employment, with most (34%) entering family life later (the ‘Work, Later family’ group), with nearly as many entering family life earlier (the ‘Work, Earlier family’ group at 32%). Conversely fewer than half of women (47%) were in a group characterised by long-term full-time employment. The ‘Part-time work, Earlier Family’ was the most common group (18%) for women.

Similar proportions of men and women were in the ‘Work, Cohabitation, Later Parent’ group (7% and 5%, respectively), the ‘Work, Marriage, Non-Parent’ group (8% of men, 9% of women) and the ‘Work, No Family’ group (13% of men, 10% of women). Only 4% of women were in the ‘No Paid Work, Earlier Family’ group, and few men or women were in groups characterised by marital dissolution, teen parenthood or weak ties to work or family.

Early parenthood – poorer health

As we expected, those men and women who were in full-time long-term employment, were married and had children later on enjoyed better health. Early parenthood, especially teen parenthood was clearly linked to poorer health, regardless of whether they were in paid work or in a stable long-term marriage.

For example, the waist circumference of teen parents was four inches larger, on average, than those who were in full-time long-term employment, were married and had children later (fat accumulated around the waistline is known to be particularly risky for health). Groups who entered parenthood earlier had 10-18% more fat circulating in the blood and 2-8% less of the ‘good’ HDL cholesterol than those who were in full-time long-term employment, were married and had children later.

Teen parents tended to be less well educated, which accounted for some of the link. However, even those who had stable employment and marriages, but had children early, had poorer health.

It seems that for both men and women, having children early is linked with poor health later on, possibly as a result of chronic stress from parenting in straitened circumstances with fewer financial and emotional resources.

Less human and social capital

Authors of other studies showing links between early parenthood and health problems such as depression, heart disease and long term illnesses, speculate that younger parents have accumulated less human and social capital to cope with the stresses of parenting. It is also possible that those who are older when they become parents have had time to establish healthier behaviours such as exercise and healthy eating prior to starting their families, making it easier to maintain those behaviours through the busy parenting years.

There is need for further evidence on how timing of parenthood influences health and we are currently replicating this study with participants from the 1970 birth cohort.

In the meantime, perhaps those family planning discussions around finances, careers and childcare should incorporate an extra question? If we have a child now rather than later, how might it affect our health later on? It’s a question that will be of interest not just to prospective parents, but to all those concerned with improving the long term health and well-being of our society.

Work-family life courses and metabolic markers in mid-life: evidence from the British National Child Development Study is research by Anne McMunn, Rebecca E Lacey, Meena Kumari, Diana Worts, Peggy McDonough and Amanda Sacker.

Photo credit: Darren Johnson

 

How travelling to work can work for you

There can’t be too many commuters who aren’t now aware that ditching the car and walking to work is much better for them. Considerable evidence has shown that walkers and cyclists are likely to weigh less and be slimmer than their car commuting counterparts. What they may be less aware of is that ditching the car in favour of the bus, train or the tube could have nearly the same benefits. A programme of research by a team at the London School of Hygiene and Tropical Medicine and the ESRC International Centre for Lifecourse Studies, UCL has been taking a closer look at the benefits of being an ‘active commuter’. As researcher Ellen Flint explains, the findings point to some clear ways forward, not just for individuals, but for policy makers too.

Physical inactivity and being sedentary for large parts of the day are a leading cause of obesity and premature death. In England alone something like two thirds of adults do not meet the recommended levels of daily exercise. At the same time there are growing numbers of people commuting to work. In England and Wales that figure is around 24 million people, 67% of whom take the car.

The time of life when most adults become obese is in middle age, with 50-65 year-olds less than half as likely as young adults aged 16-29 to use public transport, nearly half as likely to walk to and from work and two thirds less likely to get on their bikes. So it’s this age group that we have focused on in our programme of research looking at the relationship between active commuting and obesity in mid life.

To help us do this, we have used information from a long term household survey called Understanding Society and a large study called UK Biobank.

Public transport benefits

Our first piece of research used Understanding Society and showed us that not just walking or cycling to work but even catching the bus or the tube are all linked to lower body weight and body fat composition compared with those who get to work by car.

7,534 BMI and 7,424 percentage body fat measurements from men and women who took part in the survey were used in conjunction with information about journeys to work.

Men who commuted via public or active modes had BMI scores around 1 point lower than those who used private transport, equating to a difference in weight of 3kg (almost half a stone) for the average man.

Women who commuted via public or active transport had BMI scores around 0.7 points lower than their private transport using counterparts, equating to a difference in weight of 2.5kg (5.5lb) for the average woman.

When it came to body fat, men who actively travelled to work (walking, cycling or public transport) had body fat that was roughly one per cent point lower than those who commuted by car, confirming the picture seen when looking at BMI.

What’s important to note here is that these differences are larger than those seen in the majority of individually focused diet and physical activity interventions to prevent overweight and obesity.

Second study reinforces

In work just published in The Lancet Diabetes and Endocrinology, we were able to use information from more than 70,000 men and 80,000 women aged 40-69.

More than 60% of these people commuted by car, with only 4 percent and 7 percent respectively reporting walking as their only method of commute and 4 percent and 2 percent cycling. Around one in five was an active commuter some or all of the time.

Except for those who mixed car and public transport, all other groups had significantly lower BMI and percentage body fat than those men and women who ONLY commuted by car.

The biggest differences were for cyclists and the results stayed strong even when we accounted for a wide range of other factors such as social and economic background, their general health and even whether or not they did exercise outside of their daily commute.

The men who cycled were around 5 kg lighter whilst women cyclists were on average nearly 4.5kg lighter than their car commuting counterparts.

Unsurprisingly, walking to work had the next biggest association with reduced obesity. Compared with their car commuting counterparts, men who walked to work were on average 3.0kg lighter; and women typically weighed 2.1kg less.

However, what was perhaps more interesting, and what also reinforced our interesting earlier findings from Understanding Society, was that even those who used a mixture of public transport and active methods of commuting still had significantly lower BMI and body fat percentage than those who commuted exclusively by car.

In fact, it was similar to those who only walked to work. Compared with car commuters, men and women who mixed public transport with some walking or cycling typically weighed 3.1kg and 2.0kg less, respectively.

Active commuting at heart of policy

Separately these two studies make interesting reading, but together they combine to make a powerful and growing body of evidence around the benefits of active commuting and do more than hint at potential interventions for policy makers.

There is now a clear case for the health benefits of active commuting to be taken into consideration by transport planners, town planners and urban designers.

Cities can be active by design and the more evidence that we have to confirm that people who commute actively really are lighter and have a healthier body composition, the more impetus there is for these health related outcomes to be at the heart of policy.

It is time to realise the untapped population health improvements potential of these big shifts we can make in how people travel to and from work.

Photo credit: Chris Rubberdragon

Can unemployment kill – Podcast

Our first blog showcased recent research from the team at ESRC International Centre for Lifecourse Studies about the links between long term unemployment and stress markers linked to killer diseases. If you were interested in that, you can also listen on Soundcloud to researcher Amanda Hughes discussing the research for the ICLS Podcast.

Can unemployment kill?

At the height of the recent recession around 2.7 million people were unemployed, and youth unemployment accounted for nearly 40 per cent of that total. Given growing evidence that unemployment is linked to long term illness and increased mortality, we can expect health implications for those affected. In a week when unemployment rose for the first time in over a year, Amanda Hughes presents new evidence from the ESRC International Centre for Lifecourse Studies on the links between unemployment and killer diseases such as heart disease.

In 1984 a study was published which had linked census data to mortality records and found that men unemployed in the week of the 1971 census were 36 per cent more likely to have since died than men of the same age who had been in work. Accounting for differences in social background only explained part of the excess, raising the question: can unemployment kill, and if so how?

That unemployment might damage health was not a new idea. Marie Jahoda’s research on unemployment in the 1930s had shown that the non-financial benefits of work, such as defining aspects of status and identity and providing regular social contact, are for many people crucial to mental wellbeing. And since job loss usually brings a sharp drop in income, it is intuitive that unemployment could affect physical health by reducing quality of diet or opportunities for exercise.

But there tends to be more scepticism as to whether serious physical illness or mortality could be causally influenced by the undoubtedly stressful experience of unemployment. Might those unemployed men have developed serious illness when employed, lost their jobs as a result, and then died from their illness? Or might their increased mortality simply be caused by unemployed people smoking and drinking more? In neither case could it be claimed that unemployment itself has caused any deaths.

New approach

Since the 1980s, the tools available to scientists researching the health impacts of social conditions have moved on considerably. One new approach involves molecules called ‘inflammatory markers’ which circulate in the bloodstream and appear to be influenced by stressful experiences.

Elevated concentrations have been found in the recently bereaved and caregivers; inflammatory markers are also typically higher for people of disadvantaged socioeconomic position as measured by income or occupational social class. Crucially, raised concentrations of these molecules are linked to atherosclerosis and predict heart disease, presenting a possible causal pathway between a stressful social environment and increased mortality.

It was for this reason that we wanted to see if two inflammatory markers – C-reactive protein and fibrinogen – were elevated in jobseekers compared to employed counterparts.

We used the Health Survey for England and Scottish Health Survey, annual government surveys used to track changes in the health of both countries’ populations. To isolate elevations in these molecules due to unemployment-related stress, we considered a number of additional factors beyond participants’ age and gender.

To rule out elevations due to serious illness predating job loss, we considered whether participants had a long-term illness of any type. To rule out elevations caused by disadvantaged socioeconomic position more generally, we took into account housing tenure and occupational social class from current or most recent job.

Finally, to test whether elevations might be explained by worse health-related behaviours of jobseekers, we took into account participants’ smoking, alcohol consumption and body mass index.

Stress markers

In our sample of over 23,000 men and women of working age, unemployed people had elevated circulating levels of both molecules even after consideration of these factors. These differences were moreover clinically relevant, since unemployed participants were 40 per cent more likely to have C-reactive protein over 3mg/L, the level at which cardiovascular risk becomes elevated.

Effects were not uniform across the population. Firstly, older jobseekers (48-64) were more affected than younger jobseekers. This might indicate that unemployment is more stressful for jobseekers facing age discrimination, or equipped with outdated skills.

Since older jobseekers will have accumulated more unemployment over their lifetimes than younger counterparts, it could alternatively indicate that long-term or repeated unemployment is especially damaging to this aspect of health.

Secondly, we found substantial differences in results by country, with much greater elevations in both molecules for jobseekers in Scotland than in England. Data from the Labour Force Survey and the British Household Panel Study show that during the years of data collection (1998-2010) unemployment was higher in Scotland than England, and unemployment spells on average longer, which suggests two possible explanations.

Firstly, the jobseekers in Scotland may have been unemployed for longer, or had more recent unemployment spells, than English counterparts. Secondly, unemployment could be more stressful in times and places where the background rate is higher, since jobseekers will rationally perceive their prospects for re-employment as worse.

Since these surveys only collect information from people at one point in time, it was not possible in this analysis to investigate effects in the context of people’s employment histories. But unpicking these explanations will be crucial if we are to better understand the conditions under which unemployment is most likely to damage health, and which groups are most at risk.

Crucially, given last week’s news of a 21,000 rise in unemployment for the first time in a year  to 1.7 million people, policy makers interested in the long term health of the population should not divert their gaze from its wider consequences.

Photo credit: Kate Hiscock

Further information

Amanda Hughes is a Senior Research Officer at the Institute for Social and Economic Research at the University of Essex.

Elevated inflammatory biomarkers during unemployment: modification by age and country in the UK is research by Amanda Hughes, Anne McMunn, Mel Bartley and Meena Kumari and is published in the Journal of Epidemiology and Community Health.

References

Unemployment and mortality in the OPCS Longitudinal study is research by K.A Moser, A.J Fox, and D.R. Jones, and is published in the Lancet.

Unemployment durations: evidence from the British Household Panel Survey is research by K. Long and is published in Economic & Labour Market Review.