Contrarian Camel

Contrarian views on economics, healthcare and technology

Category: Diet

  • Does obesity really cost the UK £126 billion per year?

    A study has found that obesity costs the NHS £126 billion per year.

    Having gone through a PhD in the economic costs of disease I don’t even need to read the study to know the given figure is meaningless. Studies claiming that ‘disease x costs the economy y amount’, otherwise known as cost of illness (COI) studies, are widely perceived as a joke, even by the economists who make them.

    You only need to look at systematic reviews to see why COI studies are so poorly regarded. The costs for any given disease can vary wildly from negative costs to millions of pounds per person. One review found that the total healthcare costs for a number of common diseases in the US were double the country’s entire health spending.

    Even in theory, few economists agree on how the costs of illness can be measured. A particular point of contention is how to measure lost productivity, i.e. the output a sick (or dead) person would have produced had they been well. Many researchers just multiply the average wage by the number of people unable to work, which tends to produce a high illness cost, while some assume that any ill workers will be replaced and only a friction cost should be counted. The ‘correct’ cost (whatever that even means) is likely somewhere in between and dependent on the particular illness and conditions of the economy. But these are hard to measure and tend to give a lower cost, which doesn’t make such a good headline.

    But what about the healthcare costs? Surely we can measure these? In practice it’s complicated. Healthcare systems tend not to have accounts divided up by disease and attributing healthcare costs to a particular disease is tricky. Even calculating the overall cost of a particular patient’s treatment in the NHS relies on a lot of guesswork and averaging, as there are many fixed costs and variable costs to be considered. In addition, many diseases can be risk factors for other diseases. Should we include the costs of these diseases? It’s not an easy question. We might simply take the excess costs of people with the main disease, but if we also did this for the other diseases and added all the net costs, the combined total could be higher than the actual overall costs. We can adjust for comorbidities but the causal chains are so complex that separating out disease costs is always problematic. Economic deprivation underlies much obesity and many other diseases, so is the cost of obesity not ultimately the cost of economic deprivation? I would go even further and say that the economic costs of obesity are part of the costs of modern capitalist society (in other types of society obesity is extremely rare). Attributing these costs to particular diseases is impossible on theoretical and practical levels.

    Ultimately, the costs of an illness are not measured but imputed on the basis of many questionable assumptions. In theory they are the savings that would be made if the disease did not exist. But we can’t measure this counterfactual and in most cases it’s too abstract to relate to anything concrete.

    Another problem with COI studies is that better treatment and improved survival tend to raise illness costs, which seems counter-intuitive. For instance, cancer is becoming more expensive because new treatments are costly and survivors are living longer, hence using more healthcare. This actually isn’t an error; the costs to healthcare systems really do go up as we are seeing.

    Hence COI studies give the rather strange conclusion that the richer a country is, and to some extent the better its healthcare system is, the more costly disease becomes. So diseases prevalent in developed countries, like cancer and diabetes, will appear more costly than, say, malaria in the Global South. In essence, COI studies tend to be a combination of how much we can pay to treat a disease with the average wages in a country, and the main determinants are how rich the country is and how disruptive the disease is (or perceived to be). And if we choose to put more resources into a disease based on these costs, the costs will rise even further, compounding the problem.

    What about the suffering an illness causes? Why do we not see studies with disease x causes y suffering? While we may use lives lost, we don’t have an objective measure of suffering. We could use QALYs or DALYs but few people understand those. Most people understand money though, and a big sum of money sounds impressive. But couldn’t we assign monetary value to the suffering? We could do this, and some economists do, but it entails many dubious assumptions and can lead to double counting as economic analyses tend to consider costs per QALY.

    In many ways these studies underestimate the true costs of a disease, particularly in diseases affecting poorer countries, for reasons described above.

    But even in Britain, what about the cost to all our lives of being overweight? And what about the risk factors for other diseases? The £126 billion (less than £2000 per person) if anything underestimates the actual cost.

    Most of the problems with COI studies have been known since the 1960s. So why do researchers keep producing them?

    • they make headlines
    • we (or at least politicians) care more about the economy than well-being
    • we don’t question the validity of things we agree with
    • only things that are measured matter (to politicians).

    COI studies are basically lobbying disguised as scientific research. The obesity study may be driven to encourage and justify adoption of weight loss drugs. Alternatively, it might be to prod politicians towards taxing junk foods. I don’t think this is a bad goal, but it won’t solve much.

    If we eliminated obesity, would we all be a couple of thousand pounds richer? It’s unlikely. The costs would migrate somewhere else. Modern healthcare systems are engaged in a game of whack-a-mole. Fix one issue another pops up. The tacitly assumed but never publicly acknowledged underlying fact is that improved health ultimately leads to worse health and higher costs. This is because improved healthcare leads to increased longevity and it’s widely accepted that ageing populations are the main cause of increased healthcare spending. If we cured cancer it likely wouldn’t save any money because of all the additional spending on dementia care and other diseases in old age, in addition to the increased spending on pensions. That’s not to say curing cancer wouldn’t be worthwhile, just that economic grounds shouldn’t be the main ones for treating diseases.

    It’s a symptom of modern Britain that the cost to the economy is considered more important than the cost to actual people.

  • Does drinking champagne really reduce the risk of cardiac arrest?

    The headline: Drinking champagne could reduce risk of sudden cardiac arrest, study suggests.

    But does the study actually suggest that?

    The full text article. For some reason scientific articles don’t get linked to in newspaper stories.

    The study used data from the UK biobank and the authors attempted to reduce confounding and show causality through Mendelian randomisation.

    However, the authors acknowledge that confounding is due to much more than genetics. Despite the Mendelian randomisation, it doesn’t seem that confounding was handled well in this study.

    Now it may well be that alcohol intake improves cardiovascular health. More likely they are both associated with socialising and higher socioeconomic status, which have positive effects on health in many ways, and may themselves be the result of better health.

    The study found a stronger protective association for wine and champagne than for beer and cider. This suggests an underlying association with socioeconomic status and socialising: people who drink wine and champagne will tend to be richer and socialise more than beer and cider drinkers. Further evidence of this is that loneliness and isolation were negatively associated, as were depression, tenseness and other negative feelings.

    The study also found that using a computer reduced risk of cardiac arrest. However, playing computer games raised the risk. So what does that say about using computers? Not much I suspect.

    Using sunscreen had lower risk, which was likely due to higher sun exposure and taking more holidays.

    Hand-grip strength had the second strongest protective association (just behind forced expiratory volume). Does this mean that exercising your hands will the reduce risk of cardiac arrest? Maybe a little bit but probably less than going for a walk. More likely hand-grip strength reflects underlying fitness.

    Unfortunately cross-sectional studies using public data are always prone to confounding, and seldom identify primary causes.

    They lead to data dredging for associations that are trivial, spurious or incidental. They throw up all these unhelpful headlines that cause confusion and distrust, while doing little to reduce health burdens. They take away resources from higher quality longitudinal studies.

    In any case, the difficulty in reducing health problems is with effecting lifestyle and societal changes, not identifying risk factors. We have a pretty good idea of which things are good and bad for health.

    The problem is that most people don’t follow the guidelines. And ultimately if people want to engage in unhealthy behaviours that’s their choice.

  • How can we reduce the ingestion of microplastics?

    Once thought inert, plastic has been found to disrupt endocrine function while contributing to allergies, inflammation and even cancer. Global treaties on its production and disposal are sorely needed. But what can we do as individuals to limit our personal exposure to plastic and prevent its accumulation in our bodies?

    How does plastic get into our bodies?

    Due to the complexity of the problem and the lack of studies, the pathways by which microplastics (MPs) reach our bodies are not well understood. A single MP of size 1 µm to 5 nm can break down into billions of nanoplastics of less than 0.1 μm. Airborne MPs are believed to be the main source. These are of two types: indoor and outdoor.

    Outdoor MPs mostly derive from vehicle tyres. Other sources include paint and litter and just about anything made of plastic that sits outside and gets worn down and blown away by wind.

    Indoor airborne MPs mainly arise from degradation of household plastic products,e.g. synthetic furniture, carpets, electronic equipment, paint, kitchen utensils, clothing and footwear.

    After airborne MPs, the next biggest source is ingestion through food and drink. Drinking water and other liquids from plastic bottles are high in MPs, tap water less so. Seafood and salt are high in MPs due to the concentration of ocean plastics. That doesn’t mean other food is clean; the accumulation of MPs in rivers, sewage sludge and the atmosphere makes pretty much all food contaminated. Plastic packaging contributes further. Even products in metal and glass containers are not immune; tin cans have plastic linings and the tops of glass containers contain plastic. Teabags can also contain plastic while disposable coffee cups usually have plastic linings. Food containers, cooking utensils and cleaning products can also contribute. Non-stick linings in pots and pans can contain plastics that leach during cooking.

    Other sources are beauty products and toiletries. These generally come in plastic packaging and some products contain microbeads, though these have been banned in many countries. Toothbrushes have plastic bristles which degrade over time, releasing MPs into the gums and throat.

    Absorption through the skin is believed to be much lower than through the digestive and respiratory systems, but can still contribute. Using smartphones, computers, remote controls and other plastic devices introduces MPs to our skin, which may cause inflammation. Synthetic clothing is an additional source of MPs on the skin, and contributes to airborne and water-borne MPs. Childrens’ toys are most often made of plastic, and likely to get rough treatment.

    What can we do to reduce intake?

    Given the omnipresence of MPs, particularly airborne ones, is it even possible to substantially minimise exposure? Other than moving to rural areas and avoiding busy roads our capacity to avoid outdoor MPs is limited. The move to electric vehicles may make the problem worse because EVs tend to be heavier than ICE equivalents.

    However, some evidence suggests that indoor MPs contribute more than outdoor ones. Reducing these may entail substantial changes to our homes, such as replacing or covering synthetic carpets, furniture, electrical equipment and clothing, but is at least within the power of individuals. Bear in mind that disposing of plastic textiles and other household items could create additional plastic pollution.

    Other ways of reducing MP intake are:

    • use tap water rather than bottled water
    • buy fresh, local produce rather than packaged supermarket items
    • use alternatives to sea salt
    • use raw food products rather than processed food
    • avoid plastic in cooking and food storage: e.g. non-stick pans, plastic food processors, plastic containers
    • use natural cleaning products
    • wear clothing with natural fibres where possible
    • wash synthetic clothing separately with a microfibre filter
    • avoid paints that contain plastic and synthetic varnishes.

    The extent to which such measures can reduce plastic in the body is unknown, but could be substantial. And many of these measures will promote health and ethical consumption, so are worth doing for their own sake. Ultimately, though, microplastics are impossible to avoid and, like most things pollution-related, individual actions have limited effects.