Determinants of population health

Background

The health survey for England shows us that, in 2019, 28% of adults were obese and 36.2% were overweight (NHS, 2020).  Obesity is defined as a body mass index (BMI) of 30 or above, whilst overweight is defined as a BMI of 25 to 30 (Centers for Disease Control and Prevention, 2020).  This paper will address the issue of overweight and obesity in England and critically assess the claim that ‘national ministries of health have limited capacity to address the most important determinants of population health’.

Obesity is recognised as a distinct disease characterised by the abnormal accumulation of adipose tissue resulting in the predisposition for metabolic dysregulation and insulin dysfunction and their associated adverse health effects (Sam and Mazzone, 2014).  Obesity is important because it contributes to increased rates of morbidity and mortality (Solomon and Manson, 1997).  It is also causally associated with several serious medical conditions including, but not limited to, type 2 diabetes mellitus, osteoarthritis, atherosclerotic cardiovascular disease, and certain cancers.  Whilst the prevalence of obesity is rising across Europe, it is rising more so in England, where the prevalence has almost doubled over the last 10 years (Agha and Agha, 2017).

Public Health England estimate that the NHS spent £6.1 billion on overweight and obesity related ill health between 2014-15, and that the annual spend on obesity and diabetes related illnesses is greater than the budgets for the police force, fire service and judicial system combined (Public Health England, 2017).  The societal impact of obesity is far wider still, resulting in detriment to national economic development, with an estimated economic impact equivalent to £27 billion annually (Public Health England, 2017).

A person living with obesity is likely to live between 3 to 10 years shorter than their normal weight counterpart (University of Oxford, 2009).  However, within those afflicted by obesity, the disease burden is not evenly distributed.  The term “socioeconomic inequality in obesity” used by Zhang and Wang, in their 2004 paper, clearly highlights degrees of inequality when comparing obesity, socioeconomic status, gender, age, and ethnicity (Zhang and Wang, 2004).  The obese disease state is complex in that it is not binary.  The extent to which the disease penetrates different populations in society is uneven, as is the impact upon its sufferers.  Jackson et al, help us to understand that obesogenic environments help to maximise genetic expressions of body weight by making healthy choices more difficult.  In this sense, societal constructs can act to severely disadvantage those with genetic predispositions to this disease state (Jackson, Llewellyn and Smith, 2020).

Socioeconomic status (SES) and obesity

In high income countries, obesity is more commonly seen in deprived communities (Żukiewicz-Sobczak et al., 2014).  Indeed, adults in the most deprived regions of high income countries have almost double the prevalence of obesity compared with the least deprived regions (Batterham, 2020).  On this topic, Drewnowski and Specter, in their 2004 review, highlight four important factors.  Firstly, that obesity is linked to poverty and educational attainment.  Secondly, that there is an inverse relationship between energy density and energy cost, in that, energy dense food may represent the lowest cost option for consumers.  Thirdly, there exists a link between the palatability of high energy products and higher energy intakes.  Finally, Drewnowski and Specter highlight the link between poverty and food insecurity, leading to reduced investment in more expensive high quality foods such as fresh fruit, vegetables, lean meats and fish (Drewnowski and Specter, 2004).  Their succinct breakdown of the issues on this topic helps us to appreciate that to tackle obesity in high income countries, one must consider and address the factors contributing to poverty and educational attainment.

Age, sex, race, and obesity

Sadly, the challenge is more complex than poverty and education, with other confounding factors that must also be considered.  For example, weight increases with age from early to middle adulthood.  This is consistent between the sexes with minor ethnic differences.  However, a noticeable difference can be seen between SES, obesity and age, with a progressive observable disparity affecting women to a greater extent than men.  Baum and Ruhm use educational attainment as their marker of SES and therefore suggest that “the beneficial effects of childhood advantage translate into future outcomes” (Baum and Ruhm, 2009).  We should take from this the need to consider the factors that influence the development of obesity and poverty in early life, with a strong focus on educational achievement in women in particular.

Evidence based policies

Whilst the relationship between obesity, poverty, educational achievement, sex and age are not completely understood, a significant body of evidence clearly exists on the topic, enabling national ministries of health to begin to create evidence based interventions.  The policy paper “Tackling obesity: empowering adults and children to live healthier lives” published in July 2020 is the most up to date articulation on the direction of travel by the Department of Health and Social Care on obesity in England.  This governmental white paper is a policy document that sets out proposals for future legislation and is due to be implemented in April 2022.  Predecessor strategies were published in 2016 and 2018 (Department of Health and Social Care, 2016, Department of Health and Social Care, 2018).  Indeed, since 1992, the English government have published 14 different obesity strategies containing a total of 689 policies, some of which were repetitious (THEIS and WHITE, 2021).    Despite this, the prevalence of overweight and obesity has risen from 53.85% in 1993 to 64.2% of the English population in 2020 (House of Commons Health Committee, 2004, NHS, 2020).  One might suggest that something isn’t working to turn the tide on obesity in England, although it is hard to tell if any of these strategies have been successful in slowing progression of the disease across the population.  Theis and White are much less forgiving in their conclusion, stating,

“The government obesity strategies’ failure to reduce the prevalence of obesity in England for almost 30 years may be due to weaknesses in the policies’ design, leading to a lack of effectiveness, but they may also be due to failures of implementation and evaluation. These failures appear to have led to insufficient or no policy learning and governments proposing similar or identical policies repeatedly over many years. Governments should learn from their earlier policy failures.” (THEIS and WHITE, 2021).

Whilst Theis and White demonstrate 30 years of policy failure in England, they do not address the question of whether the Department of Health and Social Care (DoHSC) actually has the capacity to influence the relevant aspects of public health pertinent to this disease.  Their analysis is, however, helpful in demonstrating a predilection in England for policies that reflect capacity building and restoration by responsible actors, operating in high trust environments, irrespective of conflicting interests (THEIS and WHITE, 2021).  One could hypothesise that the likely reason why these approaches have been preferred in England is to avoid authoritative approaches that would be unpopular with a democratic electorate.  Indeed, the alternative to a high trust environment is the “nanny state” reflecting an “unnecessary approach into people’s lives and what they do, eat and drink.” (Jochelson, 2006).  Jochelson tactfully suggests use of the term stewardship instead of nanny state based upon objective evidence that shows the positive impact of education, taxation, and restrictive legislation on individual choice resulting in better health outcomes.  In her 2006 paper, she cites examples of education and proscribing of behaviours in combination with legislation as effective in reducing drink driving, smoking, and driving without seat belts.  She also links taxation, limitation in access and the banning of advertising with reductions in both alcohol intake and smoking.

The argument in favour of the interventionalist “stewardship” approach to policy outlined by Jochelson appears compelling and so we must ask why after 30 years of lack of achievement in tackling obesity, policies have been repeated and strategies have not changed.  To answer this question, it might help to look at what has happened with obesity strategies elsewhere in the world.  Take Australia and New Zealand as examples.  Their efforts to tackle obesity began in the 1980s, and so, gives us decades of experience upon which to reflect.  The scathing review by Swinburn and Wood highlight the enormously successful lobbying pressure by the food industry in those countries which has managed to deeply embed itself in the policy making infrastructure.  The world view of individual responsibility and choice without policy support to empower healthy environments in which to make healthy choices, is cited as a reason why significant inroads have not been made into resolving the obesity epidemic (Swinburn and Wood, 2013).  Sadly, the experiences of our antipodean friends sound eerily familiar with pro-choice policies being favoured by legislators, either because of fear of losing public support or because of influential lobbying pressure.  It is at least helpful for us to recognise that a theme is emerging that may contribute to our understanding of past policy failures, and so may guide us to make more effective policies in the future.

Benchmarking

Martin et al. took this theme to a new level when they published their government benchmarking framework on obesity prevention, which they called the Obesity Action Award.  The framework, which was first developed in 2008, encompasses nine domains that reflect current best practice in tackling obesity, including;

“whole-of-government approaches; marketing restrictions; access to affordable, healthy food; school food and physical activity; food in public facilities; urban design and transport; leisure and local environments; health services, and; social marketing.” (Martin et al., 2014).

Despite this framework being 14 years old and the only published tool to compare governmental obesity strategies, the literature is extraordinarily quiet in reference to it.  Consequently, without having undergone rigorous peer review one must question its validity and applicability.  Publications citing the use of the Obesity Action Award are hard to come by, and so, we must confidently conclude that a reliable system of ranking governments based upon the adoption of evidence based policies to tackle obesity does not currently exist.  However, assessing the validity and applicability of this tool would be a very useful area for future research and publication.  Indeed, a similar approach is taken for reviewing the implementation of tobacco control in the Tobacco Control Scale, so why not for obesity? 

The example of tobacco

The Tobacco Control Scale (TCS) was first described in 2006 by Joossens and Raw and has subsequently been published a further five times between 2007 to 2019 under the auspices of the Association of European Cancer Leagues.  The Joossens and Raw TCS is based on six policies described by the World Bank which they say should be prioritised in a comprehensive tobacco control programme (World Bank, 2003).  In brief, the TCS includes the following metrics; price of cigarettes and other tobacco products, smoke free work and other public places, pending on public information campaigns, comprehensive plans of advertising and promotion, large direct health warning labels, and treatment to help dependent smokers stop (Joossens, 2006).

The TCS is particularly useful because it provides a method of holding national policy makers to account by comparing and ranking their successes or failures in implementing evidence based policies.  The TCS is also helpful because it champions a global approach to best practice and provides clear instruction on how to achieve positive outcomes.  The TCS could provide a useful foundation for the creation of a food and beverage control scale utilising similar metrics to help us address obesity and overweight in the same way we address tobacco consumption.  So, we must return to the question of why this is not already in place.

Government action to control the consumption of harmful substances is not without controversy and challenge.  Indeed, there are a number of high profile cases of legal challenge from global brands against governments who try to implement statute to improve the health of their citizens.  For example, the legal challenge by the tobacco giant Phillip Morris against the Australian government took 6 years to resolve and ended in a £12million loss for the country despite “successful” defence of the legislation (Ranald, 2015).    The time and cost implications of being involved in such legal dispute with industry leaders is a significant handicap to progress for high income countries, and the example set by these world famous cases serves to restrict policy changes in low income countries who may not be able to afford to defend legal challenge.

The example above reveals the aggressive defence of the global tobacco industry worth $932 billion in 2020 (Grand View Research, 2021).  In contrast, the estimated worth of the global food and beverage industry was $3,233 billion in 2021 (Report Linker, 2021).  When trying to understand the capacity of the DoHSC to address obesity and overweight in England, we need to consider the impact of lobbying and threat of legal challenge, irrespective of the existence of high quality evidence to inform policy.  Afterall, what good is there in understanding how to address a disease state when you are prohibited from implementing effective solutions?

Poverty and education

Whilst the appetite to tackle big food and drink may be anorexic due to the real or perceived threat of industry challenge, we still have strong evidence telling us that the solution to obesity and overweight is the reduction of poverty and the improvement of educational attainment.  In 2020 NHS England and NHS improvement (NHSEI) commissioned an independent report to consider how the NHS can better tackle poverty.  Whilst the acknowledgement of the role of poverty and education in health outcomes is appreciated, the report details no new strategy and continues to champion the ineffective advocacy approach of past policies, mentioned earlier in this paper.

“more focus is needed on the three As of awareness, action and advocacy: awareness of poverty and how this changes people’s needs and interactions with services; action in the design of care but also through the impact of the NHS as an economic and civic power; and advocacy for tacking poverty, given that the NHS and its staff have such powerful and influential positions in society” (Fenney and Buck, 2021).

The educational approach seems uncoordinated, at first glance.  The last government document on this topic was published in 2011, promising a strategy to end childhood poverty by 2020 (Department for Education, 2011).  The document was produced by the Childhood Poverty Unit and was sponsored by the Department for Work and Pensions and the Department of Education, and HM Treasury.  A refreshed strategy was promised in 2014, but sadly, never materialised.

However, impressive steps were seen following the welcome publication of the government guidance ‘Childhood obesity: a plan for action’ in 2016 (Cabinet Office, 2016).  This document paved the way for the implementation of the ‘sugar tax’ in 2018 (HM Treasury, 2018), sugar reduction strategies (Public Health England, 2017), healthy environment healthy choice agendas, support with access to vitamins and healthy foods (NHS, 2019), embedding healthy diets into schools, and enabling clearer food labelling, amongst other evidence based obesity strategies.

The ‘Childhood obesity: a plan for action’ document feels refreshing in that it seeks to address some of the key issues in the causation of obesity and overweight, including aspects of poverty and education.  However, it fails to focus efforts of women, which we highlighted as a key factor earlier in this document and does nothing to address the causation of poverty and poor educational achievement which are precursors to disease states.  Time will tell if these policies can be successfully implemented or whether industry will seek to challenge legislation through legal channels or through enhanced lobbying efforts.