A human rights-based, regime interaction approach to climate change and malnutrition: Reforming food systems for human and planetary health

The modern, global food system is unsustainable for both human and planetary health. The widespread consumption of highly processed foods and use of production systems that negatively affect the environment have led to a rise in nutrition-related diseases and exacerbated the effects of climate change. A comprehensive reform of global food systems and diets is needed to effectively respond to this problem, but the interference of food industry actors in health negotiations is diluting health policies at both domestic and international levels. This article establishes the concrete value of international legal responses grounded in human rights for tackling the global syndemic of climate change and malnutrition. The Framework Convention on Tobacco Control (FCTC) exemplifies how normative conflicts between the trade and health regimes can be overcome. Forming an effective and egalitarian response to malnutrition and climate change will require a rights-based, regime interaction approach that prioritizes human and planetary health over private interests.


INTRODUCTION
The modern industrial food system is damaging both human and planetary life and health. 1 Our model of food production and consumption has created diets that are increasingly reliant on highly processed foods, contributing to one third of the global population being affected by undernutrition or obesity. 2 Moreover, food production is responsible for approximately 30 percent of global greenhouse gas emissions. 3 Climate change and malnutrition combined create risk factors for all chronic, or non-communicable, diseases (NCDs), including diabetes, cardiovascular disorders, cancers, and respiratory diseases. In 2019, The Lancet Commission published 'The Global Syndemic of Obesity, Undernutrition, and Climate Change', which portrays these phenomena as a 'syndemic', meaning 'a synergy of epidemics, because they co-occur in time and place, interact with each other […] and share common underlying societal drivers'. 4 The Lancet Commission urgently calls for policy and law to create more sustainable systems of living and eating in light of the damaging effects of modern diets and food systems on human health and the environment. 5 The global syndemic is a human rights issue: it is incompatible with the rights to health, food, and a healthy environment. States have legal obligations to protect and promote human rights, and thus a duty to respond to this problem. 6 However, human rights-based approaches (HRBAs) for responding to the syndemic have received minimal attention. 7 This article assesses the value of human rights in responding to the global syndemic of climate change and malnutrition, proposing that international human rights law can provide a normative framework for reforming global food systems, but argues that this framework needs strengthening by interacting with other regimes.
The globalised nature of the food system connects various regimes of international law: trade, health, environment, and human rights. Involving different legal systems and global actors is thus essential for forming a solution. International environmental law norms (most importantly, the UN Framework Convention on Climate Change or UNFCCC), global health policies adopted under the auspices of the World Health Organisation (WHO) and nutritional recommendations from the Food and Agricultural Organisation (FAO) can all be used to guide States towards effective policies for reforming food systems in compliance with their human rights obligations. This article focuses particularly on the role of the WHO and global health law.
Sections 2 and 3 outline the problem and establish the importance of international legal responses to the syndemic. The added value of human rights for reforming food systems in an effective and egalitarian way is then outlined in section 4, followed by a discussion on the problematic role of the food industry, a key syndemic player, in section 5. Its lack of accountability under international human rights law and the fragmentation of international law, leading to conflicting norms and standards, is discussed. Section 6 outlines how normative conflicts between the public health and trade/investment regime have been overcome under the Framework Convention on Tobacco Control (FCTC), leading to positive outcomes for public health and ultimately proving that human rights can be upheld through other regimes.
Finally, section 7 proposes that the WHO should model its approach to diets on certain aspects of the FCTC in order to regulate the food industry effectively. Drawing on lessons from the FCTC, it makes recommendations for reforming food systems under an integrated approach, using regime interaction to strengthen the human rights framework. Ultimately, the syndemic response should draw on the strengths of international human rights law and overcome its weaknesses through its connections to other regimes to find effective and equitable solutions to the global syndemic.

THE PROBLEM: GLOBAL HEALTH AND ENVIRONMENTAL CHANGE
'Malnutrition is the main cause of death and disease in the world', according to the WHO. 8 Malnutrition, encompassing undernutrition, overweight, and obesity, 9 affects every country and over one third of the global population. 10 It is a key risk factor for NCDs (including diabetes, cardiovascular diseases, cancers, and respiratory diseases) which are responsible for 71% of global deaths. 11 Over the last fifty years, the availability of high-calorie, nutrient-poor foods, as well as global demand for meat, dairy, ultra-processed foods and sugary drinks, has skyrocketedat the expense of micronutrient diversity and fruit and vegetable consumption. 12 The globalisation of unhealthy diets is thus a major determinant in the rise in nutrition-related NCDs. 13 Concurrently, globalisation has dramatically changed food systems. Increased resource use for crops and livestock production, the use of pesticides, and agricultural intensification to respond to population growth have aggravated toxic emissions in air and water sources, caused a decline in biodiversity, and eroded soils. 14 Food systems drive deforestation, loss of biodiversity, and are responsible for 20-35% of greenhouse gas emissions, according to the FAO. 15 Modern global dietary patterns therefore have devastating impacts on the environment. The link between food systems, climate change, and global health has been recognised by the WHO. A subsequent investigation of the mutually beneficial effects of environmental and NCD mitigation measures 16 resulted in the consensus that these twin challenges would benefit from coordination of policy agendas. 17 Global dietary patterns are therefore the problem and the solution because they sit at the centre of health and sustainability concerns. 18 An international legal intervention appropriate to tackle both issues is urgently needed. 19

THE ROLE OF LAW
Since the twentieth century, law has increasingly been recognised as a public health tool. 20 Through normative frameworks establishing legal responses to public health threats, law protects individual and community health by enforcing policies that guarantee people's safety, access to health services, and healthcare infrastructure. 21 Law can either be 'hard' (binding, legally enforceable obligations), or 'soft' (non-binding agreements often found at the international level). 22 The progressive acceptance of the role of law in global health is visible in the emergence of global health law, which focuses on the international dimensions of health. This commonly includes the global governance regime developed and implemented by the WHO, or more broadly, '[all] the legal norms, processes and institutions needed to create the conditions for people throughout the world to attain the highest possible levels of physical and mental health'. 23 Global health law can thus incorporate all legal fields touching upon public health. 24 The growing recognition of law's function in NCD responses has led some to state that 'the question is no longer whether Legal interventions can thus be used as a 'dynamic', effective tool for addressing public health issues. 31 The reciprocal relationship between domestic and international levels of law, and between domestic jurisdictions, should be seen as interactive and synergistic rather than as a straightforward vertical relationship. A key legal participant in diets is the trade regime: the establishment of the WTO in 1995 provoked a reduction in trade barriers and increased industry's role in shaping food and dietary preferences through aggressive marketing of unhealthy foods. This, in turn, precipitated the rise in nutrition-related NCDs. 32 A legal approach to increasing food industry accountability would balance out this deregulation process. 33 Law is therefore an essential tool in the development of NCD prevention and control strategies, and is key in the syndemic response. 34 International law, in particular, sets global benchmarks against which States can measure their actions. International targets such as the Sustainable Development Goals (SDGs) are important for the framework they provide, setting an authoritative and high standard. 35 Their 'softness' allows for the participation of a larger number of actors from the international arena, such as non-governmental organisations and 27. Eg: Ukraine, after ratifying the WHO FCTC on 6 June 2006, developed a national programme which increased excise taxes seven-fold and the price of cigarettes three-fold. Ratification of the FCTC is said to have given it 'the momentum' required to successfully put tobacco taxes on the agenda. A combination of actors at both levels is thus needed to implement the international framework at the domestic level. WHO, '

THE VALUE OF HUMAN RIGHTS
International human rights law is a valuable but overlooked tool offering many advantages for tackling climate change and unhealthy diets. First, it aims to provide protection for the weakest. This is crucial as the greatest burden of the syndemic is currently borne by those with the least means to respond to it, with 80% of NCD deaths occurring in low-and middle-income countries. 37 In wealthier countries, vulnerable and marginalised groups are more affected by NCDs than higher-income groups. 38 In terms of climate change, the poorest 1 billion people in the world contribute only 3% of global pollution, yet these populations are most affected by environmental damage. 39 Economic inequalities have been linked to worse health outcomes. 40 Consequently, integrating equity into public health 41 laws can mitigate the root causes of ill-health. Governance addressing malnutrition and climate change should therefore strive to alleviate these inequalities, and international human rights law, which guarantees the right to equal treatment through its core principles of equality and non-discrimination, is key for embedding these in the syndemic response. 42 Second, international human rights law offers a comprehensive, normative foundation covering the syndemic issues. When States ratify a human rights treaty, they become bound by the obligations contained therein and commit themselves to 'respect, protect and fulfil' individual freedomsa tripartite breakdown of their duties to 'do no harm', protect from abuses, and take positive action, respectively. 43 International human rights law thus 'identifies who has rights (rights-holders) and what freedoms and entitlements they have […], as well as the obligations of those responsible for making sure rights-holders are enjoying their rights (duty-bearers)'. 44  (as duty-bearers) have legal obligations to realise the rights to food and health of their populations. 45 The syndemic engages both of these rights, as well as the emerging right to a healthy environment. 46 Individuals (as rights-holders) often have legal avenues to raise claims against the State pertaining to breaches of these rights. 47 Certain aspects of the rights to food and health are legally enforceable. 48 Several domestic constitutions recognise their justiciability: 49 for example, the constitutional protection of the right to health proved essential in the fight for access to HIV/AIDS antiretrovirals (ARVs) in South Africa. In Treatment Action Campaign (TAC) and others v Minister of Health, the South African Constitutional Court held that, as socio-economic rights are 'clearly' justiciable, the limited availability and accessibility of Nevirapine constituted an unreasonable restriction to the progressive realisation of the right to health care. 50 After the judgment, the government adopted an official policy of treating HIV with ARVs, 51 which is estimated to have saved 6.15 million adult life years between 2000-2014. 52 The TAC case shaped the current South African HIV/ AIDS policy, demonstrating how litigation in individual cases can improve public health policies overall, and it created judicial precedent of using legal action to enforce constitutional human rights 45. International Covenant on Economic, Social and Cultural Rights (adopted 16 December 1966, entered into force 03 January 1976) 993 UNTS 4 (ICESCR), arts 11, 12. 46. The right to a clean environment exists in regional treaties and in over 60 national constitutions. The OHCHR states: 'while the universal human rights treaties do not refer to a specific right to a safe and healthy environment, the United Nations human rights treaty bodies all recognise the intrinsic link between the environment and the realization of a range of human rights, such as protection. 53 It also proves the value of civil society's promotion of human rights, as the TAC successfully mobilised affected groups to campaign for better treatment through health education strategies. Human rights can therefore be enforced nationally, and these legal accountability procedures can help to shape policies improving individual access to healthy and sustainable foods.

ESTABLISHING THE 'SYNDEMIC RIGHTS'
The Committee on Economic, Social and Cultural Rights (CESCR), mandated with monitoring the ICESCR's implementation, has interpreted the right to health as containing four essential qualifiers: availability, accessibility, acceptability, and quality (AAAQ). 54 The underlying determinants of health are composed of 'a wide range of socio-economic factors that promote conditions in which people can lead a healthy life', 55 including food and nutrition. The right to health is thus closely linked to the right to food, 56 which entails access to 'sufficient, adequate, and culturally acceptable food that is produced and consumed sustainably, preserving access to food for future generations'. 57 In a similar way to the AAAQ, the right to food contains four components necessary for its realisation: availability, accessibility, adequacy, and sustainability. Adequacy is stressed here: the right to food relates to the right to 'a standard of nutritional quality and not just to a minimum quantity of calories'. 58 Moreover, it demands 'both sustainability and satisfaction of dietary needs'. 59 With nutrient-poor diets being among the main causes of malnutrition, these twin qualifiers of adequacy and sustainability encompass both the health and environmental issues at the core of the syndemic.
The 'greening' of human rights in recent decades entails 'the understanding that a healthy environment is of fundamental importance to the full enjoyment of a vast range of human rights, including the rights to […] health [and] food.' 60 Environmental issues can thus be addressed through the right to health's underlying determinants, which include a healthy environment, and the right to food, which explicitly refers to sustainability and obliges States 61 to improve methods of production, conservation and distribution of food by making full use of technical and scientific knowledge, by disseminating knowledge of the principles of nutrition and by developing 53. Mark Heywood, 'South Africa's Treatment Action Campaign: combining law and social mobilization to realize the right to health' Under the right to food, States must therefore ensure that food systems use natural resources efficiently. A self-standing right to a healthy and sustainable environment is also emerging, 63 which, if adopted, should require 'a system of food production and consumption that mitigates the health inequities and the effects of climate change' and 'include […] the right to environments that promote healthy food, active living, and active transportation and that permit physical activity at workplaces and educational institutes, including usable green spaces.' 64 The emerging right to a healthy and sustainable environment combined with the rights to food and health are thus directly relevant to syndemic concerns and contain important potential for developing legal responses to the problem. Combined, they represent States' binding commitments to empower individuals to pursue healthy and sustainable lives and should act as a mutually reinforcing framework.
Human rights bodies could refer more consistently to international standards from other regimes (and their corresponding actors) to guarantee that the syndemic response defines concrete strategies for reforming the food system. For instance, the UN Human Rights Council (HRC) states that environmental standards set in compliance with human rights should 'be consistent with all relevant international environmental, health and safety standards, such as those promulgated by the […] WHO'. 65 The CESCR also finds that fulfilling the right to health comprises a distinct requirement of health promotion, 66 including 'the dissemination of appropriate information relating to healthy lifestyles and nutrition', 67 and that the WHO is critically important in this regard. 68 These references could be more consistent, specific, and clear regarding how States should consider other norms and bodies when implementing human rights. The WHO, in turn, should provide the technical guidance for States' implementation of human rights, 'translating' the human rights framework into concrete legal strategies and holding States to account for action on health.
The interdependence of the rights to food, health, and a healthy environmentthe syndemic rightsare thus a key starting point for exploiting the advantages of the human rights framework and forming a comprehensive, normative, and multidisciplinary foundation for reforming diets. The international syndemic response should guide States towards effective national policies for creating and sustaining 'enabling food environments', which entails making 'the healthy and sustainable food choice the default choice, while limiting the promotional opportunities for foods associated with unhealthy and unsustainable diets'. 69  actor accountability, and the fragmentation of international law, which has led to issues of conflicting norms, endangering human rights implementation when faced with challenges from the food industry.

PRIVATE ACTOR ACOUNTABILITY?
Inevitably, the food industry plays a major role in diets, operating independently of States and not bound under international human rights law. Nonetheless, under its duty to protect human rights, governments must take positive action to prevent violations by other actors, including food corporations. 71 This includes 'requiring business entities to exercise human rights due diligence in order to identify, prevent and mitigate the risks of violations of Covenant rights'. 72 Consensus has formed around the notion that transforming food environments is necessary to effectively change individuals' food consumption, 73 which implies the need to regulate the food industry to enable consumers to make healthy and sustainable choices. Imposing human rights due diligence on food corporations is thus essential for protecting the syndemic rights. Governments should, accordingly, impose regulation such as food taxes and subsidies, as well as labelling and marketing restrictions 74 in other words, legislative limitationson the food industry. 75 The CESCR confirms this, holding that due diligence measures may also cover 'restricting marketing and advertising of certain goods and services in order to protect public health, such as of tobacco products, in line with the [FCTC].' 76 Extending these measures to marketing restrictions within the food industry is therefore also acceptable. The CESCR further asserts this in relation to intellectual property rights, which may also hinder the realisation of human rights: 'States parties have a duty to prevent unreasonably high costs for access to […] food production […] from undermining the rights of large segments of the population to health [and] food'. 77 Ultimately, intellectual property rights are 'a social product with a social function', not to be equated with human rights. 78 The Committee further details States obligations with regard to diets, including to 'redirect investments in agricultural development away from the exclusive focus on boosting the production of cereal cropsrice, wheat and maizetowards support for healthy diets, including adequate measures to reduce the excessive intake of sugar'. 79 The Committee on the Rights of the Child (CRC) also mandates States to regulate targeted advertisements to children 'to prevent children's exposure to the promotion of unhealthy products'. 80 It is therefore clear that States' human rights obligations extend to regulating private food actors when their activities interfere with syndemic rights. The application of human rights in the private sphere is known as 'indirect horizontal effect': while the State is held directly responsible for the violation, the non-State actor is indirectly obliged to comply. 81 In parallel, the CESCR recently reaffirmed businesses' human rights responsibilities in the Covid-19 context. They are obliged, 'as a minimum, to respect Covenant rights', 82 and urged to prioritise health rights over intellectual property rights. This 'corporate responsibility to protect' was endorsed in 2011 through various non-binding instruments emphasising the responsibilities of non-State actors vis-à-vis human rights. 83 However, regulating non-State actors, which lack legally enforceable and direct accountability under international human rights law, remains difficult. This is problematic, as the food industry can significantly obstruct States' abilities to realise individuals' syndemic rights.

FRAGMENTATION: THE CHALLENGES OF REGULATING 'BIG FOOD'
The expansion of international law over the last half-century has led to the emergence of multiple specialised regimes, such as international human rights law, international environmental law, trade and investment lawa phenomenon known as fragmentation. This has led to issues of conflicting norms, with no clear hierarchy between these regimes. States may thus face difficulties implementing their obligations under the syndemic rights when these conflict with other international rules, such as trade regulations. Moreover, food industries (commonly referred to as 'Big Food') frequently engage in aggressive lobbying against the adoption of strict health regulations, promoting weaker policies to advance their own interests. Big Food's interference in the development of health strategies combined with its lack of direct accountability under international human rights law is a major obstacle to effectively responding to the syndemic. These industries often challenge States when they impose trade-restrictive measures on them to protect the syndemic rights. States' regulatory autonomy in the field of health is therefore limited by their competing trade and investment agreements, as jurisprudence indicates that 'particularly stringent health claims regulations will be challenged as a trade barrier'. 84 For example, Chile's legislation mandating front of pack nutrition labelling on products with high fat, sugar, or salt content was challenged by a US domestic trade association 85 over its legality under WTO law, a legal battle compounded by the food industry's aggressive lobbying against the policy. States lack the technical legal capacity to defend against such challenges. Big Food's political and corporate power 87 creates a clear 'imbalance between the strong global policy norms regarding trade (economic interests) and weak global policy norms regarding nutrition policy' (health interests). 88 Conflicts of interest between private actors and syndemic concerns also arise under international investment law. In the climate field, challenges are levelled under international investment law when regulations complying with climate treaties trigger State liability under investment treaties in the energy field, most notably the Energy Charter Treaty. 89 This has also occurred with food: in 2021, a cereal company started proceedings against Mexico for implementing a labelling regulation on ultra-processed foods. 90 Compensation costs are high in investor-State proceedings, with disputes costing governments an average of 315.5 million USD between 2017 and 2020. 91 The threat of a lawsuit 'raises the cost of policy action', 92 which may have a chilling effect 93 on States' willingness to adopt domestic measures complying with climate and/or health regulations, and can discourage other countries from following their example. 94 87. 'Big Food' uses lobbying but also 'public outreach and the media to present their views on the nutritional aspects of their products, which shapes public perceptions and the broader regulatory environment', as well as

RESOLVING NORMATIVE CONFLICTS THROUGH REGIME INTERACTION
In 2006, the International Law Commission (ILC) addressed the problem of fragmentation. 95 It recalled customary law principles which require interpreting treaties in light of other rules and principles of international law applicable between the parties, including human rights (systemic interpretation). 96 Margaret Young elaborated on these recommendations, arguing for a 'legal framework of regime interaction' to address fragmentation. 97 Young claims: the 'productive friction of regime interaction may lead to a more responsive and effective international legal system than the sum of the constituent regimes.' 98 Regime interaction is crucial for regulating diets as it allows the normative framework of human rights to be upheld by other regimes and can lead to positive outcomes for the syndemic rights. Systemic interpretation in favour of human rights has been used in both national and international litigation. The FCTCa treaty 'guaranteeing the human rights to health' 99illustrates how productive regime interaction between the trade, public health, and human rights regimes has allowed tobacco-control measures (TCMs) to withstand normative challenges from States and industry.

REGIME INTERACTION AT THE WTO: PLAIN PACKAGING
Regime interaction under the FCTC has led to favourable outcomes for public health measures in trade and investment disputes. At the WTO, this occurs through 'balancing' assessments which involve evaluating the necessity and proportionality of a measure to determine whether it violates trade laws. This is coherent with the systemic interpretation rule. 100 WTO dispute settlement procedures must therefore consider States' public health commitments, including the FCTC, as part of the 'relevant rules […] applicable between WTO members' 101 when interpreting WTO agreements. TCMs adopted in pursuit of FCTC obligations that are not overly trade-restrictive will thus generally withstand normative challenges based on WTO rules. In Australia -Tobacco Plain Packaging, the Panel determined that 'the improvement of public health by reducing the use of, and exposure to, tobacco products is a "legitimate objective" in the context of article 2.2 of the Technical Barriers to Trade (TBT) agreement'. 102 Further, these measuresbased on FCTC Article 6were not 'more trade-restrictive than necessary' to achieve the legitimate objective (proportionality test). Balancing assessments are applied to identify whether a measure is, for example, a protectionist measure prioritising domestic products, hence violating WTO law, or a 'bona fide public health measure', in which case outcomes tend to favour health. A non-discriminatory, FCTC-compliant public health measure is thus likely to be found compatible with WTO law. FCTC implementation and the adjudicatory bodies' deference to public health protection as a legitimate objective is a valuable example of regime interaction which could also function for regulating diets.

PHILIP MORRIS AND THE ROLE OF THE FCTC
Investment tribunals may also consider legal conflicts in light of States' public health and human rights obligations under a regime interaction approach. The Philip Morris judgment, in which the tribunal upheld the legality of TCMs enacted by Uruguay to protect public health, underscores the FCTC's importance in three respects. First, it sets judicial precedent of systemic interpretation leading to favourable outcomes for public health and human rights under international investment law. Unlike in WTO adjudication, investment arbitration tribunals rarely use systemic interpretation to resolve legal conflicts, despite most investment treaties providing for this. 103 However, in Philip Morris, the tribunal referred explicitly to the 'particular relevance' of the FCTC, finding that Uruguay's measures were 'adopted in good faith', 'non-discriminatory', 'proportionate', and 'effective means to protecting public health'. 104 The balancing tests adopted heresimilar to those at the WTOled to the tribunal upholding the legality of Uruguay's TCMs, dismissing Philip Morris' claims. Second, the judgment reflects the tribunal's willingness to accept States' 'right to regulate', a central aspect of their duty to fulfil human rights, 105 even when this conflicts with investment agreements. The UN High Commissioner for Human Rights states: 'to the extent that investment agreements concern human rights issues, States have a duty to regulate (the duty to fulfil human rights).' 106 The FCTC allowed the tribunal to directly engage with human rights arguments, when assessing 'the conflicting obligations of Uruguay […] (the investors' rights) and the right to health of its population under external rules (other international agreements).' 107 Without referring to other human rights treaties, the tribunal posits the FCTC as the international agreement protecting the right to health. 108 Thus, the tribunals' deference to States' regulatory freedom in measures pertaining to the right to health is reflective of the FCTC's value as a public health tool protecting human rights, 109 despite not being a human rights treaty. The FCTC acquires the role of reinforcing the relevance and importance of the right to health in such judgments, demonstrating how human rights and health law mechanisms can complement and reinforce each other, and 'possibly sending a signal for potential future arbitrations'. 110 Finally, Philip Morris highlights the role of international organisations (IOs) in supporting governments to implement public health policies. Both the WHO and the Pan-American Health Organisation (PAHO) submitted separate amicus briefs to the tribunal. The WHO brief detailed evidence of tobacco-related health risks and the rationale for Uruguay's measures, without adopting a position on the dispute. Both briefs also described State practice in tobacco control and supportive of Uruguay's measures. 111 This illustrates the value of regime interaction and the function of IOs in guiding tribunals to understand the law in the context of other systems, rather than in a vacuum. The briefs may have assisted the tribunals' reasoning by helping it to understand the implications of its judgment. Finally, this also underscores the importance of IOs in supporting States in their health policy implementation. 112 The tribunal's acceptance of the brief demonstrates the WHO's potential weight in international forums, and the need for it to continuously back States' rights to regulate to protect human rights. The FCTC is so far the only example of a global health treaty standing up to the private sector. Many lessons must be drawn from it in addressing the syndemic.

LESSONS FROM THE FCTC
The tobacco example could thus pave the way for effectively reforming diets. The acceptance of FCTC-compliant public health-based measures in litigation supports the argument that regime interaction can lead to the interpretation of international rules in favour of the right to health. Key to achieving a similar outcome for diets and climate change is ensuring that any future syndemic legislative guidance is evidence-based and supported by the relevant IOs. 113 The WHO brief in Philip Morris was found to be unbiased and probably influenced the court by providing empirical evidence of tobacco's negative effects on health and State practice of successful tobacco control policies.
The support of IOs will also encourage States to be bolder in their syndemic policies with the knowledge that tobacco litigation has prioritised health over private interests. The legal precedent in Plain Packaging of trade-restrictive measures pursued in the interest of health withstanding WTO investigation has stimulated other States to follow Australia's examplethe number of States with plain packaging rules almost doubled within 2 years. 114 This has created a sense of legitimacy around such measures and shows the horizontal effect of domestic laws on other jurisdictions. The acceptance of States' right to regulate in this case and in Philip Morris may extend to future syndemic-based rules, but the WHO, human rights bodies, as well as the FAO and the UNFCCC must provide the guidance and support needed to inspire States to take such risks. 115 More generally, this shows that human rights and health law can act as a mutually reinforcing frameworkas stated, it was thanks to the FCTC that human rights were even mentioned in Philip Morris. Conversely, the FCTC can use human rights 'as a powerful engine to advance the tobacco control agenda', 116 and 'protect public health interests from the commercial and other vested interests of the tobacco industry', as article 5.3 FCTC urges. 117 Accordingly, human rights bodies are using ratification and implementation of the FCTC as an indicator of compliance [with the right to health] as shown for example by General Comment 15 by the Committee on the Right of the Child […] and by the inclusion of FCTC implementation in concluding observations on periodic reports by states parties. 118 This strongly indicates that global health and human rights mechanisms should collaborate to strengthen the implementation and enforcement of syndemic measures. The acceptance of the WHO's brief in Philip Morris demonstrates the dynamism of the international legal system and that IOs should interact with each other to ensure its coherence. Uniting the regimes and actors relevant to the syndemic will reinforce the consistency and therefore strength of any measures adopted to respond to it, as the risk of costly arbitration procedures is omnipresent. Explicit norms are required to acknowledge and manage the conflicts of interest between these regimes and ensure that syndemic concerns are not reliant on a favourable interpretation by the judge. 119 The tobacco example is, so far, the most successful treaty in regulating a commercial health-harming product, with 'nearly 22 million future premature smoking-attributable deaths' averted by virtue of the implementation of key FCTC demand-reduction measures between 2007 and 2014. 120 The WHO can reproduce this approach to help States realise healthy and sustainable food security for all.   124 In most States, the approach to curbing the rise in nutrition-related NCDs through dietary regulation has been to provide individuals with nutritional information, 'empowering' them to make sensible and healthy decisions when buying and consuming food. 125 Accordingly, policy interventions aimed at the nutritional environment that reduce or prohibit access to certain unhealthy food products are minimal, despite this being required under international human rights law and one of the more effective ways of regulating diets. 126 Attaching responsibility to the individual for making healthy dietary choices is problematic. Firstly, behavioural studies show that consumer empowerment methods are largely ineffective, 127 partly because removing nutrition from the realm of State or industry responsibility and placing it entirely in the hands of the individual 128 disregards the social determinants affecting individual choice of food product. Accessibility and affordability fall outside the realm of personal control. Hence, this is also inconsistent with States' human rights obligations, which they fail to meet by not bringing healthy, sustainable food choices within everyone's reach. 129 The WHO should more assertively shift responsibility away from the individual and advocate for a broader notion of responsibility for dietary health. 130 One way to undermine the 'individual responsibility' approach and the perception of industry's legitimate involvement in the policy discourse on NCD-prevention is to demonstrate the similarity between tobacco and certain foods. The example of 'hyperpalatable', or high fat, sugar, or salt foods, which 'can stimulate neural circuits similar to those that are stimulated in cases of drug addiction', 131 most clearly supports this logic. It is thought that nutrition-related illnesses may be exacerbated by the neurological effects produced by high fat, sugar, or salt foods. 132 Though the 'addictiveness' of foods cannot fully explain the rise in nutrition-related NCDs, this at least shows that industry is not exempt from responsibility, as its influence effectively limits individual control over food choices. Addiction 1208, 1208.
Secondly, the 'individual responsibility' approach legitimizes Big Food participation in WHO consultations, through which it obstructs the adoption of nutritional policies. The WHO's stance on the food industry's role is ambiguous, 133 and it fails to establish which associations should be made with it. 134 On the one hand, it includes Big Food in negotiations: the Global Strategy on Diet 'explicitly encourage[s] governments to consult stakeholders on policy, including the private sector and the media, […] [and] to establish mechanisms to promote their participation in activities related to diet, physical activity and health'. 135 The WHO's starting position is therefore that Big Food can positively assist in nutrition-related disease control. 136 Food industry actors exacerbate this in WHO consultations by presenting themselves as 'part of the solution', stressing the importance of public-private engagement in the NCD discourse. 137 The WHO's active involvement of industry in NCD-prevention negotiations may even make matters worseattempting to unite conflicting interests could stifle any meaningful reform. 138 For instance, the WHO encourages States to follow the Codex Alimentarius Commission labelling standards on the one hand while also advising that they exceed them. 139 States often challenge each other for doing the latter, 140 which demonstrates their unease about the potentially trade-restrictive nature of health claims on foods and uncertainty regarding the legality of such measures. Clear WHO guidance on how to exceed these guidelines without being challenged by the trade industry would quell these concernsarguably, the WHO is aware of industry's heavy involvement in Codex discussions and their resulting weakened nature; hence its encouragement to go beyond them. However, it has so far failed to be explicit in this regard.

DISEMPOWERING BIG FOOD
Conversely, the FCTC's success can be explained by the WHO setting clear limits on industry's interference in health negotiations. It materialised through the engagement of multiple stakeholders in tobacco control and careful consideration of the 'conflicts' between health, trade and investment law. The giant tobacco industry with unbridled power over the consumer seemed to leave States with little regulatory swayyet the Convention was a success, portraying tobacco as 'a health rather than trade or agricultural topic', and was an exercise of the WHO's 'epistemic authority' through its strict stance on tobacco. 141 It urges States, 'in setting and implementing their public health policies with respect to tobacco control [to] act to protect these policies from commercial and other vested interests of the tobacco industry in accordance with national law'. 142

'Big
Tobacco' is thus clearly portrayed as an illegitimate participant in the debate because of its vested interests in promoting a health-damaging product. In discussions leading up to the FCTC, the damaging effect of tobacco trade on health outcomes was explicitly addressed. 143 Moreover, tobacco was 'de-normalised' as a major NCD risk factor 144 and treated as a fundamentally toxic product, thanks to scientific evidence proving that there is no safe level of exposure to tobacco. The fact that food does not suffer from the same stigma as tobacco posits the food industry as a more acceptable participant in the dialogue on NCD prevention, which partly explains the WHO's ambivalence in this regard. 145 Big Food, clearly, cannot be discredited to the same extent as Big Tobacco, simply because not all food products are 'toxic'. However, considering the damaging health effects of industry's aggressive promotion of unhealthy foods, 146 the ineffectiveness of voluntary nutritional guidelines premised on 'consumer empowerment', and the addictive nature of certain food products, food industry responsibility in the NCD-crisis cannot be ignored. 147 Moreover, it is responsible for around one quarter of greenhouse gas emissions. 148 The WHO's persistent ambivalence on how to address Big Food 149 has allowed the 'development of industry voluntary commitments […] instead of legislation', 150 emphasising that it has a moral, not legal, responsibility to respect human rights. 151 Though companies cannot be held legally accountable under international human rights law, the FCTC proves the WHO's power to issue norms addressing the impact of private actors on health. 152 Irrespective of their binding or non-binding nature, such norms will only be effective if they acknowledge and address the conflicts of interest arising between these regimes. It is crucial to limit Big Food's involvement in health negotiations in order to prevent the industry from diluting public health measures aimed at responding to the syndemic. Recognising that individual choice of food product is largely determined by external factors, including the effectiveness of government policies in regulating industry actors, will stimulate the needed shift towards enabling food environments which ensure that healthy, sustainable foods are the default option.
Global health promotion, part of the WHO's mandate, is defined as 'the process of enabling people to increase control over, and to improve, their health'. 153 Helping States to create food environments which encourage healthy diets will actually increase individual control over food choices, because it will enable them to make healthy and sustainable food choices free from the external influence of the food industry. The WHO therefore has the duty and the power to issue authoritative guidance on industry engagement in this field.

REFORMING DIETS AND FOOD SYSTEMS: AN INTEGRATED APPROACH
Effectively responding to the syndemic calls for an integrated approach, combining the strengths of the different actors involved while adopting an FCTC-like stance towards the food industry. Overall, rights-based approaches can strengthen national endeavours to respond to the global syndemic by highlighting States' obligations to respect, protect, and fulfil individual rights to healthy and sustainable food security and to regulate the 'commercial' determinants of diets 154 by addressing the food industry. It is at this stage that international human rights law needs other regimes to support the required regulatory action.
First, the WHO should explicitly recommend excluding Big Food from health negotiations. As stated, 'to foster [concerted government efforts to regulate company behaviour], part of the role of the private sector is, simply put, to stay out'. 155 Even the 2021 UN Food Systems Summit included industry, sidelining human rights and allowing it to commit to voluntary private sector pledges, thereby distracting from any meaningful systemic change. As with tobacco, the WHO must urgently and explicitly underscore the 'fundamental and irreconcilable conflict between the [food] industry's interests and public health policy interests'. 156 Second, the WHO should offer stricter regulatory guidance which will translate into effective national policies. This should go beyond 'consumer empowerment' methods such as providing nutritional information and focus on policies that make individuals' nutritional environment healthier and more sustainable. These include food composition, labelling, pricing, and promotion. 157 Pricing policies can be very effective; 158 however, such measures are likely to be met with strong industry interference in the form of lobbying at the negotiation stage or legislative challenges after implementation.
Step one is therefore crucial and step two should be followed by advice on managing conflicts of interest. The WHO's 2015 guidance on pricing policies does not comprehensively address industry challenges. 159 It merely states that 'price policies for food are susceptible to being widely opposed by […] industry, further limiting their uptake and […] strength', and mentions whether the 'industry sentiment' to each policy is positive or negative. The WHO tackled conflicts of interest in the 2016 Framework of Engagement with Non-State Actors, stating that 'WHO does not engage with the tobacco industry and the arms industry'. However, fast food industries were not added to the list due to disagreement between Member States, 160 and for the same reason, the Framework does not go so far as stating that industry must be prevented from interfering in legislative processes.
The final step is exploiting the synergy between health and human rights. The CESCR can refer to WHO documents when assessing States' compliance with the syndemic rights in its concluding observations, as it has started to do with the FCTC. 161 Exploiting the congruence between these mechanisms will strengthen the syndemic normative framework and foster accountability under the syndemic rights, as well as provide evidence-based justifications for policies that interfere with industry. This evidencethat concerted global action in the field of sustainability and diets is neededis building up: there is broad consensus that we are reaching a tipping point regarding malnutrition, food security, and climate change. The WHO should now also reinforce the consensus that Big Food is harming the environment and human health. Human rights therefore 'impose [the] minimum standards' 162 and legal obligations to be met to respond to the syndemic, and the health regime collates evidence that justifies proscribing industry interference in health negotiations. Together, these rights-based, normative, and empirical standards have more potential to be adopted at national-level, stand up to industry challenges, and thus to be implemented effectively. The upholding of syndemic policies in national and international courts, both in individual cases and against companies, can lead to the improvement of public health policy overall, enabling States to create environments favourable to the consumption of healthy, sustainable foods.

CONCLUDING REMARKS
From the viewpoint of nutritional and environmental health, the food system is the main driver of one of the most significant human and planetary challenges of our time. The global syndemic will only be effectively resolved by a comprehensive overhaul of our currently 'broken' 163 systems of producing, marketing, and consuming food. Considering the gravity of the situation, the dearth of 159. WHO Europe, 'Using price policies to promote healthier diets' (WHO 2015). appropriate syndemic response measures is cause for concern. The international community has proved what it can achieve when it harmonises its approaches to respond to global health threats, such as tobacco use. Conversely, the outbreak of Covid-19 has highlighted how vulnerable we are to crisis. History evinces that the most powerless and marginalised groups consistently suffer the most from global disasters, which further increases socio-economic inequality, exacerbates the root causes of ill-health, and perpetuates the transmission of disadvantage from generation to generation. The syndemic response must take these massive inequalities into account. A human rights-based approach that aims to mitigate these inequalities and pursues the protection of human dignity as its main objective is the most humane reaction to this emergency.
This article has established the value of international human rights law and States' commitments to respect, protect, and fulfil the rights to food, health, and a healthy environment in responding to the syndemic. It proposed a rights-based, regime interaction approach to regulate the food industry more effectively. The WHO can model its approach to diets on the FCTC to realise healthy and sustainable food security for all by restricting Big Food's ability to promote unhealthy and unsustainable products. Regime interaction between health and human rights that addresses the private industry without including it in negotiations was effective for tobacco control, and a similar process can be instigated for diets. This is key to creating an effective 'syndemic response system' which places human health above the profit-driven motives of the food industry.
It must be acknowledged that civil society action in WHO Member States was key to garnering support for the tobacco treaty, though a similar process has not yet convinced States in the World Health Assembly (WHA) to support an FCTC-like approach to diets. Therefore, though this analysis focused on the WHO's role as an agency that can provide a top-level impetus for change and have a 'trickle-down effect' in all levels of society, other actors must also be involved. Collective action from civil society is indispensable for urging government, business, and international actors to take powerful, result-oriented measures, as the Treatment Action Campaign did with HIV/AIDS. 164 Governments in the WHA must support the FCTC-like approach to diets, implement policies to curb the syndemic's progress, and monitor their effectiveness. International bodies such as the FAO and the UNFCCC Secretariat can guide States in their syndemic strategies, and domestic action is key for their actual implementation and enforcement. States may also draw inspiration from other States' successes. Human rights bodies should develop specific guidelines on the food industry's 'corporate responsibility to protect'. 165 Big Food is also capable of adapting its business model to promote healthier and more sustainable lifestyles. Health and human rights promotion strategies through the State or the WHO will enable consumers to choose healthy and sustainable diets once these have been made available to them, and