*Editors’ note – this post is part of a series on ‘The Rule of Guidance?’. The other posts in the series will be available here.

The distinction between hard and soft law that permeates discussions in international law is often blurry in the realm of domestic administrative law. In international law, soft law is usually understood as legal norms that are both non-justiciable and non-enforceable. Hard law, on the other hand, includes those norms which are both justiciable and enforceable. This distinction, as imperfect as it may be, provides a starting point to reflect on the role of soft law in domestic administrative law. States predominantly rely on a mix of hard and soft law for governance, and it is generally agreed upon that any form of governance or interference with the freedoms of individuals by states requires justification. While much has been said about the justification for states’ interference with individual freedoms, lesser attention has been paid to a different question: are states, and in this case public administration, justified to interfere only softly in circumstances where full-throttle interference is both permissible and effective? To put it in another way: in circumstances where the use of hard law would both be permissible and effective is the exclusive use of soft law legitimate?

Here I will use the example of unhealthy diets that include ultra processed foods (UPFs) and foods that are high in fats, salt, and/or sugars (HFSS) to answer this question. I’ll argue that evidence of harm caused to others is an important factor that determines the legitimacy of the use of either soft law or hard law to address a public issue (especially a public health issue). My central claim is that the stronger the evidence of harm to others, the greater is the administration’s burden to legitimise the exclusive use of soft law. While this claim may remind readers of the age-old “harm principle”, my argument’s scope is slightly different as it uses evidence of harm not only to determine the legitimacy of state interference sans phrase, but the legitimacy of choosing to softly interfere when harder interference is called for.

State interference in food and drink can be traced back to the Assize of Bread and Ale in 13^th century England; a law which regulated the price, quality, and weight of bread and ale. Regulation pertaining to the quality and sale of food and drink exists since at least that time. But if we consider state’s interference in our choices related to the things that we can consume – which is different from regulating the sale, hygiene, and quality of food and drink – it is a relatively recent affair. Dietary rules that restrict food choices have been a part of culture and communities since millennia, but the restriction of consumption choices through state regulation can be traced back to the first attempts at regulating alcohol. Today, it is widely accepted that a state has an essential interest in food consumption and its implications for population health. At the same time, individuals consider food consumption as integral to self-care and many associate food with self-identity. As such, any interference that affects what people may ingest is often a point of contestation, as seen with resistance to tobacco or alcohol regulation for instance.

The current dietary patterns in the UK are far from ideal. A study conducted in 2023 concluded that over half the calories in adults’ diets come from UPFs. As of now, there is no legal definition of UPFs; they are generally considered to be foods that contain ingredients that are not used in home cooking. They include HFSS foods but are more than that; they incorporate the process of making food wherein chemicals, colourings, and sweeteners are used to improve the food’s appearance, taste, or texture. UPFs have been linked to more than 30 different health problems, including heart disease, cancers, and anxiety. Despite that, UPFs generally have strong marketing campaigns that attract more consumers. Diets heavy in UPFs are considered a global public health threat, and the UK is one of the worst affected countries.

New research tells the same story. Toddlers are now getting nearly half their calories from UPFs. A 2024 study found that UK adolescents, between the age of 11 and 18, were getting about 2/3 of their calories from UPFs (i.e., about 66% of their calorie intake). This figure is one of the highest in the world and second only to the US where the percentage of UPF calorie intake is at 67%. A 2024 meta-analyses of epidemiological data related to ultra-processed food exposure and adverse health outcomes looked at the quality and weight of evidence of the connections between different diseases and diets high in UPFs. It found overwhelming evidence related to UPFs causing up to 50% increased risk of cardiovascular diseases related death, about 48-53% higher risk of anxiety and common mental disorders, and about 12% greater risk of type 2 diabetes. It found highly suggestive evidence of the link between UPFs and some kinds of cancers, wheezing, depression, obesity, and hypertension. All in all, we now have strong evidence of UPFs causing harm. But is this harm caused by individuals only to themselves or is it also harm caused to others? The answer to this is important for justifying state interference through hard, as opposed to soft, law.

Many would argue that the harm from unhealthy diets is harm that individuals cause only to themselves. After all, we have the liberty to choose, and we like to exercise this liberty to choose what, when, and how much to eat. Perhaps this might be a persuasive argument in countries with predominantly private healthcare. But in countries where taxpayers bear the costs for healthcare service provision, as in the UK, it is arguable that UPFs harm everyone. There is projected and real-time data on how unhealthy diets are burdening the health system in the UK, but if one were to think about the scale of this in terms of a specific example – it is estimated that treating Type 2 diabetes will cost more than treating all the cancers by 2035. In terms of productivity, there are four main health conditions that have led to 2.8 million people being both sick and out of work: Type 2 diabetes, hypertension, mental health, and musculoskeletal problems. Three out of four of these health conditions are either caused or exacerbated by unhealthy diets. Consequently, the harm in the case of unhealthy diets is not only being caused to the national health system but also to people with other serious health conditions that urgently require treatment but are being sidelined because the system is overburdened with diseases caused by UPFs. The harm is also being caused to the taxpayers financing the provision of healthcare. The harm is being caused to all because national productivity is being impacted. The notion of “harm” at work here is not a fuzzy one. There is money being lost, people becoming ill and incapacitated, and people dying. Essentially, harm is being caused not only to the self, but also to others. But in terms of the choice of legislative instrument that could tackle this issue head on, the UK government almost exclusively relies on soft law, in the form of guidance on dietary intake.

Some regulations have recently been drafted to tackle the epidemic of unhealthy diets, like The Calorie Labelling (Out of Home Sector) (England) Regulations 2021 and The Food (Promotion and Placement) (England) Regulations 2021. But these regulations (which fall within the category of hard law) cover only marketing or advertisement of unhealthy foods. They do not cover the central issue of the existence and availability and thereby the consumption of unhealthy foods. Despite strong evidence of harm, the state predominantly tackles the issue of unhealthy diets through guidance, i.e., soft law, instead of influencing the existence, availability, and consumption of such foods via hard law. For instance, the EatWell Guide by NHS that includes 5 a day campaigns, hydration, exercise, etc., and some nutritional guidance to be provided by GPs as part of their professional duties (both of which can be regarded as soft law for present purposes).

There are long standing discussions in legal and political philosophy on the relationship between law, freedom, and autonomy. The widely accepted view on hard law is that it always reduces people’s freedom. Through hard law, individual freedom is limited either through prevention of choice, prevention of an action, or through the threat of penalty. But it gets trickier with individual autonomy. Liberal democratic societies, like the UK, place a high premium on the value of bodily autonomy or a person’s ability to demonstrate power and agency over choices concerning their own bodies. In fact, most laws tend to promote that value. But some laws also restrict bodily autonomy (sometimes with good reasons, and sometimes not). It is a long-established position in legal and political philosophy that individual autonomy needs to be protected from unnecessary or arbitrary encroachment by the state.

But many also argue that the law should interfere with our autonomy when it is necessary to protect others from wrongful harm. These arguments build on the harm principle which holds that the only purpose for which the law may use its coercive power is to prevent harm to others. Following that line of reasoning, in the case of unhealthy diets, given the overwhelming evidence of harm being caused to others, the use of hard law measures is prima facie warranted. Often when there is weak evidence of harm being caused to others, governments are cautious in their choice between hard and soft law – and there are justifications for this choice. But all justifications for the choice between hard or soft law need to be made explicit for continuity of public trust in the state. It is equally important for the government to not weaken the distinction between hard and soft law. As we witnessed during the Covid-19 pandemic, there was sometimes a blurring of the distinction between law and guidance (or hard law and soft law), which risked undermining public loyalty to the law itself.

Essentially, in cases where the evidence of harm to others is overwhelming, choosing to only use soft law is to choose not to prevent serious harm to the population in circumstances where the state is justified in seeking to prevent such harm. Therefore, the administration’s choice to use soft law in the case of unhealthy diets needs to be backed by additional reasons. But such reasons are not usually given, perhaps because it is assumed – wrongly – that if one is permitted to use a more forceful mechanism of interference, one would be a fortiori permitted to use softer ones. Therefore, the government’s choice to exclusively rely on soft law, as opposed to hard law, in the case of unhealthy diets without providing stronger justifications for such choice might be illegitimate. And lastly, and importantly, if Keir Starmer and the administration think that preventable deaths is an argument that works for outdoor smoking ban, it is unclear why the same does not apply to unhealthy diets.

Himani Bhakuni, Lecturer, York Law School <himani.bhakuni@york.ac.uk>

(Suggested citation: H. Bhakuni, ‘The Legitimacy of Exclusively Using Soft Law: The Case of Unhealthy Diets’, U.K. Const. L. Blog (10th February 2025) (available at https://ukconstitutionallaw.org/))