PUBLIC HEALTH
OVERNUTRITION: A UK PUBLIC HEALTH CRISIS
Malnutrition is a huge health and human rights concern, with 800 million people in the world who are starving.1 ‘Mal’ from the French, translates into ‘bad’, so malnutrition literally translates into ‘bad nutrition’. Thus, malnutrition encompasses both undernutrition and, a more pressing issue in developed countries such as the UK, overnutrition, which includes overweight and obesity. Lifestyle diseases are non-communicable diseases, often exacerbated by lifestyle conditions or choices. Having risen substantially in prevalence in the last century,2 these are also known as ‘diseases of civilisation’ having arisen from the changes in modern society. In developed nations, we have the privilege of convenience foods and a breadth of food options. Commercialisation of food industries has engendered a shift towards processed and convenience foods, which are partly responsible for a change in a food environment that perhaps encourages less considered and mindful eating and more consumption of nutrient-sparse, high sugar, high fat and high salt products. The evolving human diet in itself may not be to blame, as this and a transition towards more sedentary lifestyles, where work and leisure are increasingly technologically, as opposed to labour directed, together have facilitated a culture in which more energy is often ingested than expended, leading ultimately to weight gain. CAN LIFESTYLE PLAY A PART?
It is very striking that certain communities, which have been historically isolated from trade with developing countries and commercial food corporations, have avoided lifestyle diseases until the introduction of convenience shops. One case study of the Arctic Inuit communities3 highlights that, whilst traditionally Inuit people consume a
very high fat and protein diet from the blubber of marine animals such as seals and whales – and some would associate high fat consumption with an increased risk of illnesses such as heart disease – the prevalence of noncommunicable disease was very low until convenience stores, akin to those in larger cities, were established as part of increased interactions and trade with the developing world. Another community, the Yakut, an indigenous Siberian population, has seen a prevalence of Type II diabetes rise4 with the onset of integration with the Eurasian market. Also, the first instance of documented obesity was recorded in another Arctic community, the Nenets in 2015.5,6 Further afield, a study which compared health outcomes of rural South Africans after trialling an American diet for 20 days, revealed that there were substantial changes to the gut microbiome and metabolome and changes in mucosal biomarkers, all of which indicate a heightened risk of developing cancer.7 Clearly, the adaptation of a Western diet influences the health outcomes of traditionally detached communities, not beneficially, but in quite the opposite direction.
Farihah Choudhury Health and Wellbeing Co-ordinator, University of Southampton Farihah is a Prospective Master’s student of Nutrition for Global Health. She is interested in public health nutrition, particularly in changing population health patterns as a result of dynamic food environments, food security and food waste, food poverty, food marketing and literacy.
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DEFINING OBESITY AND OVERWEIGHT
Obesity is defined as the build-up of excess adipose tissue. ‘Excess’ is defined according to the BMI guidelines www.NHDmag.com March 2019 - Issue 142
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PUBLIC HEALTH Table 1: BMI guidelines BMI (kg/m2)
Nutritional status
<18.5
Underweight
18.5-24.9
Healthy/normal
25.0-29.9
Overweight
30-39.9
Obese
>40
Morbidly obese
(see Table 1). Clinically, a BMI of over 25 paves the way for successive grades of overweight and obese.8 Though BMI has not always been considered the most accurate method of clinically assessing body weight alone,9 when used in conjunction with measuring waist circumference (‘central obesity’), it provides a generally accurate threshold to either alert or reassure an individual or health practitioners. In this way, BMI can be viewed as a screening tool for those who do and do not need to worry about their weight. Different thresholds exist for different ethnic groups, as well as for men and women.10 Indicators of central obesity for Europeans and Afro-Caribbeans are a waist circumference of >94cm in men and >80cm in women. On the other hand, indicators for South Asians are >90cm for men and >80cm for women.11 Physiologically, men and women have different external adipose tissue distribution. Women biologically have a higher fat retention capacity, whilst men have a higher proportion of muscle. Furthermore, men have an ‘apple-shaped’ adipose tissue distribution centred on the upper body, whilst women collect in a ‘pear-shaped’ distribution, collecting more around the abdomen and the thighs. RISKS ASSOCIATED WITH OVERWEIGHT
Overweight and obesity are well-documented as increasing the risk of developing numerous secondary diseases, including cancers, cardiovascular diseases, atherosclerosis, osteoarthritis, gallstones and Type II diabetes mellitus.12 Not only does obesity exacerbate the onset of illnesses, but it can also come with a social anxiety and shame that can prevent action to reverse poor health and have a psychological effect on the individual. Overweight and obesity in pregnant mothers increases the risk of the pre-eclampsia, hypertension 26
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and gestational diabetes, plus an increased risk of caesarean delivery, a decreased ability to give natural birth after caesarean success and an increased risk of operative morbidity. Neonates and foetuses are more likely to have preterm births, be stillborn, have higher than normal birth weights and be obese in childhood. Meta-analyses show a significant increase in neonate fatality with an increase in maternal BMI.13 In 2006, it was estimated that 18% of mothers were obese at the beginning of their pregnancy,14 and this figure is likely to have risen in recent years in line with the national increase in obesity prevalence in adults. To summarise the graveness of the risks associated with overweight and obesity, the all-cause mortality risk in individuals increases greatly with an increase in BMI above the ‘normal’ measurements15 – this is a public health issue of utmost concern. THE PROBLEM IN THE UK
Undernutrition and anorexia disorders only represent around 5% of the UK’s population.16 On the other hand, the NHS reports that 26% of adults and one in five Year 6 children were classified as obese in 2018.17 In 2002, the first recorded case of Type II diabetes in children was recorded in the UK.18 Despite rates being more stable since 2010, obesity prevalence has doubled in children and trebled in adults since the 1980s.17 This is a comparable issue in several developed countries, most shocking of all in the USA. However, despite the fact that, compared to some of our European neighbours, the UK has comparatively lower prevalence of obesity and overweight, we are the nation with the most rapid increase in overweight and obesity.17 It was declared in 2014 that “obesity could bankrupt the NHS”;19 an estimated 5.1 billion pounds was spent in 2014/15 on obesity and obesity-related conditions;20 this figure does not take into account the collateral costs associated with complications of obesity. OTHER FACTORS CONTRIBUTING TO OVERWEIGHT AND OBESITY
Physiologically, the human body is more able to cope with a lack of resources (ie, starvation), than an abundance of them. Arguably, the modern diet of excess is a new phenomenon in the evolution of our bodies. There is discourse regarding
Commercialisation of food industries has engendered a shift towards processed and convenience foods, which are partly responsible for a change in a food environment that perhaps encourages less considered and mindful eating . . .
whether we have physically developed the capacity to manage excess nutrients and, thus, have no mechanism in place to neutralise the effects of over-eating.21 The metabolic control capacities of appetite hormones such as leptin and ghrelin are still not yet fully elucidated, but their role is implicated in appetite control, as well as in many other metabolic processes. There is also select evidence suggesting that the activity of certain hormones may cause some individuals to eat more or less than others. Leptin increases when food is ingested and is said to administer a satiating effect, signalling an individual to stop eating. Ghrelin, which increases when one is hungry and decreases when one is satiated, indicates to an individual that the body is low on expendable energy. Although, historically, rodent studies administering leptin to mutant obese mice were used to determine if satiation could be achieved, results have not been successfully duplicated in humans. In fact, recorded cases of leptin deficiency are very rare. Instead, it is thought that in obese individuals, the issue is not of leptin deficiency but of leptin resistance due to defective receptors or signalling pathways. There have been developments in the research into this muddy area, for example, groups currently characterising the fat mass and obesity related transcript (FTO) gene, have identified that FTO is an important regulator of body size and composition in both rodent and human studies,22 and that FTO links high-fat feeding to leptin resistance.
It cannot be ignored that food poverty and poor food literacy create an obesogenic environment for those who are most susceptible. Public Health England (PHE) published that 7.8% of children who come from high income families are obese, whereas this figure rose to 20.7% children in low income households.23 Furthermore, misunderstanding of food labelling and portion sizes contributes to over-eating – portion sizes have increased substantially in the last few decades, so inadequate consideration of how much food is enough, or too much, may contribute to unforeseen weight gain. CURRENT INITIATIVES IN THE UK TO TACKLE OBESITY
In a government clamp down on obesity, a plan was outlined in 2016, which has been gradually enforced since its announcement.24 One major component of the outline, the sugar tax on soft drinks, has been officially in effect since April 2018,25 and drink manufacturers have been told to cut down their sugar content or pay a levy, the money raised from which is being used in school breakfast clubs. Since 2016, many manufacturers have already begun to phase out and replace sugar in their drinks. Furthermore, there have been recent talks of introducing a ‘pudding tax’ for high-calorie, high-sugar desserts, such as ‘Freakshakes’. It has been reported that, by the age of 10, children have consumed the same amount of sugar as an 18-year-old.26 www.NHDmag.com March 2019 - Issue 142
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PUBLIC HEALTH Tackling high-calorie foods in other categories, PHE have also announced potential plans to order restaurants to cut down on highcalorie menu items. Other parts of the outlined plan include working with schools to enforce 30 minutes of physical exercise a day during school hours and improving school dinners. Furthermore, PHE are working with food vendors and marketing agencies to mitigate the effects of damaging advertisements and offers. This includes removing buy-oneget-one-free deals from our shelves, and discontinuing unlimited refills of unhealthy drinks in retailers. Change4Life constantly pushes national campaigns to encourage a more active nation, although its impact is perhaps yet to be significant. The rapid increase in obesity and overweight suggests that an overhaul of all parts of the food environment needs to be implemented. This includes both changes to an increasingly obesogenic dietary environment and pushing the incorporation of more physical activity into daily lives. ATTITUDES TOWARDS OVERNUTRITION
There is something to say for the attitudes towards those who are overweight or obese, contributing towards a culture that does not help individuals to lose weight, or if they do lose weight, to maintain it. A culture of fat-shaming often blames individuals for choices they may have made, or situations they may have been in. This culture is reinforced by the media and a whole industry that often promotes unattainable standards for the general population. Overweight people are aware of being overweight and shaming does not force them into action.
Conversely, a peculiar new trend has arisen from what should be a positive place. In order to encourage and accept individuals as they are, body positivity has taken off to empower those who feel inadequate, or who had previously been villainised, which is a great development in mitigating feelings of guilt and shame in individuals. However, an extreme offshoot of this appears to be a positivity movement that glorifies overweight, which is unhelpful for individuals who would benefit personally from reducing their energy intake, for their personal health and wellbeing, as overweight-related malaise can severely impede quality of day-today life. However, despite the extremes of some movements within ‘body positivity’, the cause provides a reassuring platform for those who feel insecure about weight issues and it may actually encourage more of a healthy discussion, as opposed to ostracising those who struggle with their size. SUMMARY
Many factors have been pinpointed as the sole cause of obesity and many nutrient groups have been villainised in order to explain why the nation is becoming more obese. Nevertheless, it seems that a shift in physical activity levels as a result of leisure and work being more computer and technology based, combined with consumption of high-calorie and energy-dense foods which are available in abundance, contributes hugely to our public health crisis. However, there is research to be done on other factors which might have a greater role to play than previously thought and perhaps a rethink is needed about how we can overhaul an obesogenic environment that has failed a sizable percentage of the British population.
4TH ANNUAL PROGRAMME OF KETOGENIC DIETARY THERAPY LEARNING AND NETWORKING EPILEPSY • DIABETES • NEURO-ONCOLOGY • WORKSHOPS
4TH – 6TH JUNE 2019 www.mfclinics.com/keto-college 28
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