The fat tax chimera

A couple of weeks back I noted that Hungary’s new fat tax is unlikely to slim the populous or reduce health costs.  While MacroBusiness has a wide readership, UK Prime Minister David Cameron is clearly not amongst them, as his recent suggestion of a ‘food levy’ to battle obesity suggests. Also, it was too late to convince the Danes to back out of their fat tax.

I argued that health ‘sin taxes’ are generally ineffective at fulfilling their stated aims.  If the taxes change behaviour and improve health, public health costs will actually increase as people live longer during retirement.  But the taxes won’t change behaviour significantly.  It will simply promote consumption of close substitutes, which themselves are likely to be ‘unhealthy’.

Today I consider the implications of the uncertainty surrounding the scientific connection between dietary fat and obesity.  What if the connection is not as strong as we are led to believe? What if new data proves that in fact our fat intake is too low and causing more health problems because of our relatively high intake of carbohydrates? How would policy makers deal with new scientific findings after implementing a fat tax?  While I don’t have definitive answers, I can at least being the discussion.

Given the complexity of human metabolism (I liken the body to an economy of cells interacting to form emergent complex systems) it would only be natural that our understanding, especially of long term patterns, is far from complete.

Gary Taubes’ classic article examines the uncertainty and controversy that sits just behind the mainstream dietary advice (I strongly recommend reading the article in full even if it is a little outdated)

But it gets even weirder than that. Foods considered more or less deadly under the low-fat dogma turn out to be comparatively benign if you actually look at their fat content. More than two-thirds of the fat in a porterhouse steak, for instance, will definitively improve your cholesterol profile (at least in comparison with the baked potato next to it); it’s true that the remainder will raise your L.D.L., the bad stuff, but it will also boost your H.D.L. The same is true for lard. If you work out the numbers, you come to the surreal conclusion that you can eat lard straight from the can and conceivably reduce your risk of heart disease.

In fact a theory first promoted in 1924 by Otto Warburg (the Warburg effect) suggests that high-fat diets could play a role in prevention or treatment of cancer.  His observation was as follows.

If most aggressive cancers rely on the fermentation of sugar for growing and dividing, then take away the sugar and they should stop spreading. Meanwhile, normal body and brain cells should be able to handle the sugar starvation; they can switch to generating energy from fatty molecules called ketone bodies — the body’s main source of energy on a fat-rich diet — an ability that some or most fast-growing and invasive cancers seem to lack.

Inspired by these observations, leading researchers have conducted trials to test that very theory, with promising results.  Much of the research is now focused on ‘ketogenic diets’ (high fat, moderate protein, low carbohydrate), with results showing that high-fat diets may help in the prevention of numerous diseases. One prominent researcher is now advancing the theory that cancer is best analysed as a metabolic disease, with important implications for dietary causes and prevention.

… numerous studies show that dietary energy restriction is a general metabolic therapy that naturally lowers circulating glucose levels and significantly reduces growth and progression of numerous tumor types to include cancers of the mammary, brain, colon, pancreas, lung, and prostate.

The implication for policy makers is that taxing fats, if it effectively promotes diets with more carbohydrates (and subsequently more energy), could lead to unintended consequences in terms of the incidence of cancer, and in fact of obesity itself.

So what does this mean for the policy maker tasked with addressing the obesity epidemic?

Taubes explains some of the pitfalls-

Surely, everyone involved in drafting the various dietary guidelines wanted Americans simply to eat less junk food, however you define it, and eat more the way they do in Berkeley, Calif. But we didn’t go along. Instead we ate more starches and refined carbohydrates, because calorie for calorie, these are the cheapest nutrients for the food industry to produce, and they can be sold at the highest profit. It’s also what we like to eat. Rare is the person under the age of 50 who doesn’t prefer a cookie or heavily sweetened yogurt to a head of broccoli.

”All reformers would do well to be conscious of the law of unintended consequences,” says Alan Stone, who was staff director for McGovern’s Senate committee. Stone told me he had an inkling about how the food industry would respond to the new dietary goals back when the hearings were first held. An economist pulled him aside, he said, and gave him a lesson on market disincentives to healthy eating: ”He said if you create a new market with a brand-new manufactured food, give it a brand-new fancy name, put a big advertising budget behind it, you can have a market all to yourself and force your competitors to catch up. You can’t do that with fruits and vegetables. It’s harder to differentiate an apple from an apple.”

If the science is suggesting that high-fat diets typically lead to lower energy intake (due to satiation effects), and this is associated with better health outcomes across a variety of measures, a fat tax seems like that last this you would implement.  In fact, you would tax carbohydrates if you wanted to increase the general health of the population (but not if you were concerned about health costs), which would go some way to overcoming the carbohydrate fuelled ‘empty calorie’ trend in food marketing.

Of course, that all depends on the certainty of the science.  Neither tax seems particularly flexible to new scientific findings. I would argue that a policy intended to address obesity should be able to respond to the latest research findings, or indeed, participate in the research itself.  It appears that government involvement in preventative health would be most effective simply through research funding and promotion of trials to better understand the long term health risk associated with dietary preferences.

Is that enough for a political party to appear to be ‘doing something’ about the obesity epidemic?  This doesn’t seem like a change at all from the status quo.  However, maybe the status quo is the best option under the obvious scientific uncertainty.

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  1. Great article. My thoughts during the article were on what appears to be the elephant in the room. Refined sugar and substitutes. No health benefits, obeisity causing and potentially cancer causing. Cane sugar tax anyone?

  2. Tip: look up “paleo diet” (a.k.a. cave men diet).

    On the scientific uncertainty and legislation – don’t we see this here with the carbon tax currently being voted on?

    • Maybe there’s less public certainty (and talk-back radio certainty), but the scientific certainty is definitely stronger with climate change. Dietary interactions are very much up in the air.

      On another note, there was an episode on Catalyst that showed research into the satiation effects of fat, and found none. Close though – there is an appetite suppressant in proteins, of course which are often found side-by-side with fats.

      • Sorry Nathan. There is far more scientific knowledge of how the human body operates than the global eco/climate system. Yet we clearly don’t fully understand (yet) how the body interacts with either its environment or food sources.

        The key points in this article are:
        1/ The responsiveness of policy to changes in scientific evidence (ie. ability to change policy).
        2/ The impact of unintended consequences.

        Both of these points are validly extrapolated to the carbon tax debate.

  3. As someone who has had to deal with being overweight his whole life I can tell you that carbohydrates are the biggest culprit in weight gain, not fats.

    • That’s so true. I had a huge battle with my weight about a decade ago. Best decision I ever made was to cut right back on carbs. Now I feel healthier than I did 10 years ago!

      • rice and little else… theirs a hude difference between rice and polishing off a kg of icecream.

  4. David Gillespie’s ‘Sweet Poison’ is worth a read although my Dietician daughter has arguments with a few aspects. Nevertheless, the conclusion would be that, as far as ‘sin taxes’ go, we should tax Coca-Cola et al before and more than ANYTHING else.

    Any FAT tax should be applied to the Government itself!

    • Yep – by far the biggest problem is the way many foods are now laced with sugar.

      Fructose in particular (sucrose/cane sugar is 50% fructose) as it is the stuff that makes sugar really sweet and thus very attractive to eat. (and yes fruit juice is no better than drinking soft drink sweetened with cane sugar)

      Much of the excess consumption of refined carbohydrates and fats and energy generally is related to the almost addictive nature of foods sweetened with fructose.

      The amount of junk food and other energy dense foods that are consumed would be greatly reduced they were not ‘sweetened’.

      A tax (or even just better labeling) on the use of ‘fructose’ would make much more sense and be a lot more effective than a tax on saturated fat.

      If you like sweet things eat whole fruit when in season but if that seems a bit dramatic keep a close eye on how much food you are eating that has been juiced up with ‘sweetness’. You may be surprised.

    • Flawse, you beat me to it again! Yes, David Gillespie’s Sweet Sugar, the real culprit, fructose.

      This is a ‘must see’ for those that are interested: Robert H. Lustig, MD, UCSF Professor of Pediatrics in the Division of Endocrinology, explores the damage caused by sugary foods. He argues that fructose (too much) and fiber (not enough) appear to be cornerstones of the obesity epidemic through their effects on insulin. Series: UCSF Mini Medical School for the Public [7/2009] [Health and Medicine]

      Sounds to me that governments are doing what they always do and looking for more ways to raise revenues. That plus a stigma against the overweight that smacks of judgemental puritanism.

      Another good article Rumple.

      • I think you guys need to distinguish between ingesting something that is naturally occuring in fruits and vegetables and something that is concentrated up to give you a super dose.

        There isn’t anything on this planet that isn’t toxic in the right (wrong?) dose. My understanding of these sorts of claims is that they are railing against things like high fructose corn syrup NOT fructose at levels you ingest when you eat fruit.

      • That plus a stigma against the overweight that smacks of judgemental puritanism.

        overweight people are storing carbon so are actually doing their bit for the environment.

  5. Carbs and sugars have been shown to massively increase the bodies yeast and fungus overgrowth known as Candida. The stuff feeds on it and causes all sorts of problems throughout the body. What’s the issue with fats again? Why is a non-fat yogurt full of sugar good for you? We’ve certainly got this one the wrong way around. I have a sneaky suspicion that the herbivores have been behind this propaganda.

  6. If you have an hour & half to spare, here’s a talk call Sugar The Bitter Truth, by Dr Robert Lustig, that goes into the details of why sugar is a problem for us.
    In short, it’s the fructose half of the sugar molecule that does most of the damage, as it appears our bodies aren’t really adapted to the huge quantities we consume with a modern western diet. It’s relatively scarce in natural foods, but we’ve figured out how to concentrate it and stick it into almost everything (because it tastes good).

    Then there are those who say grains, or at least the modern (ie. fast) ways we process them are also a big problem. Traditional processing methods tend to involve a lot of slow fermentation which makes the food more digestable for humans. There are also raw milk advocates who reckon that pasturisation destroy a lot of enzimes in the milk that again, help humans digest it, hence the rise in lactose intolerance etc.

    Fast foods may be bad for us, but the animal fat content is likely the least of our worries, so I’d oppose a ‘fat tax’ on that basis alone, not to mention food taxes are the most regressive of all. I’m a non-smoker, but I also think we’ve gone too far in taxing tobacco for that reason as well.

    • It’s [fructose] relatively scarce in natural foods

      On the contrary it is relatively common in natural foods. It is the primary sugar found in fruit.

      Additionally fructose doesn’t cause they same fluctuations to insulin levels that glucose does.

      Further if you study the effects of fructose derived from sucrose (i.e. sugar) you need to figure out a way to decouple the effects of glucose (the other half of sucrose) from those of fructose. In other words studying the effects of fructose by giving sucrose wouldn’t seem to make much sense to me.

      But the bottom line to me seems to be that if you ingest something the way we have evolved to digest it you should be much better off, i.e. derive your fructose from eating fruit rather than foods rich in high fructose corn syrup. Flooding your system with anything is not likely to be positive.

      • High fructose corn syrup isn’t common in Australia, it’s a North American issue.

        Ours is cane sugar.

        • High fructose corn syrup and other high fructose product are labelled under a variety of different names and both are common in a wide range of foodstuffs (as is sugar of course).

          If you’ve not seen the Lustig presentation, set aside an hour or so – a revelation.

          • I think we are talking apples and oranges (no pun intended).

            Fructose is not a problem per se, as other commenters seem to have mistakenly concluded. It is the highly concentrated form that these types of advocates are railing against.

          • I’m not dismissing it, I’m just saying corn syrups isn’t prevalent in Australia, I know its a food additive by the truck load in the U.S. Cane Sugar based fructose is what we have.

            The other two major issues, I am of the belief anyway, are trans-fats and MSG (often labeled chicken salt). The fast food outlets use both of these galore.

            My wife and I holidayed in Paris in March, it completely changed my outlook on food.

            In nine months, I’ve lost 12kg, 5 inches off my waist, and the thing is, it has been very, very easy.

            I just do what the Parisians do.

            Eliminate virtually all simple carbs, and no carbs at all after lunch.

            Incidentally, I’ve now added cooking with butter and cream in my diet, a supposed mainstream no-no, but I’m now not convinced animal fats are as bad as vegetable fats.

      • Yes, I know it’s the bit in fruit that makes it sweet, but the amounts are tiny compared to what you get in something like a can of soft drink, plus it’s wrapped in nutritious fibrous piece of food. Also, modern fruits have been bred to be sweeter than their natural origins.

        I’d need to look into that talk again, but the he gives the reason why fructose doesn’t cause the blood sugar spike, it was to do with the way the body metabolises it, via the liver from memory.

        • By scarce I took you to mean that it was rarely present in natural foods. Sucrose is scarce in natural foods. Fructose is common. But the amounts present are tiny — as you point out. That was basically my point. When concentrated up as stuff like high fructose corn syrup you get issues. Also it is true that this is predominately an american issue because of the vast corn field there.

          Presumably it is cheaper for soft drink makers here to buy cane sugar than high fructose corn syrup otherwise they would go down that path too.

          I used to know this stuff along time ago but from memory fructose doesn’t stimulate insulin like glucose does therefore you don’t get the same spikes as you do when you eat similar quantities of glucose.

          • Actually fructose IS the problem.

            The liver readily metabolises fructose to fat rather than blood glucose. For that reason fructose usually ends up as circulating fat.

            That is the reason it doesn’t cause an insulin spike. Insulin responds to glucose in the blood.

            Thus while Fructose is low GI that is not a good thing.

            Fructose is generally fine in the small concentrations found in the quantities of fruit most people eat but most of the fructose that is being consumed comes in a highly concentrated form.

            Cane sugar and high fructose corn syrup have about the same amount of fructose. So Cane Sugar is not much better than HFC.

            Fruit juice is also a major source of fructose. Reconstituted fruit juice is just a sweetener derived from fruit rather than sugar cane. Nothing good to say about either.

            Most breakfast cereals including the museli and healthy sounding ones with nuts etc are often 25% or more sugar.

            Needless to say the industrial sugar pushers love the distraction produced by talk of a fat tax.

            If you want to crank up consumption make it sweet.

            If your mouth waters at the thought of some sweet treat chances are you are hooked on the sweet jolt of fructose.

            Pure glucose syrup is readily available – try it and you will quickly see that sugar (sucrose) gets its sweetness from the fructose half rather than the glucose. Sucrose is 50% fructose and 50% glucose.

  7. I feel that taxes on very high fat content fast foods will have a positive effect. In the last article on this topic I disputed the point that public health costs increasing per capita as a result of people living longer was flawed because it didn’t consider the increase in productivity for the same amount of time – especially in relation to the investment in skills and training already consumed by the person.

    Increasing cost is an effective practice where cost is an important factor in the decision making (or can be made an important factor if it gets too high).

    I agree with the points made, that fat in itself is not the culprit, but rather carbohydrates (especially through the use of refined sugars). However, most of the foods that would be targeted by these kinds of tax are not just high in fat, but they are high in carbohydrates as well. The kilojoule content of most fast foods is incredibly high. The types of fats in these foods are also problematic, being of the trans and saturated varieties.

    As for the substitution issue, given the choice between a person eating a high-in-bad fats and high-carb meal, I would rather see them just eating a high carb meal.

    I wouldn’t really be supportive of something that is a blanket tax on fat, rather something that is a little more targeted. As some people have suggested I think a blanket tax on sugar would likely have a much stronger effect. To this day I cannot understand why people consume so many sweetened drinks.

    • “I wouldn’t really be supportive of something that is a blanket tax on fat, rather something that is a little more targeted. As some people have suggested I think a blanket tax on sugar would likely have a much stronger effect. To this day I cannot understand why people consume so many sweetened drinks.”

      people do cos they can and want to..

      I wish people would stop trying to advocate and throw up ideas for taxes to support their own world view or self interest, let people do what they want, face the consequences and it will be much better world.

      You cant teach self responsibility if all responsibility is not in the hands of individuals, half of the time when I read MB comments its like people read BNW or 1984 and thought “hey thats a good idea, dont have to think for myself anymore”

      • “half of the time when I read MB comments its like people read BNW or 1984 and thought “hey thats a good idea, dont have to think for myself anymore””

        Really? I get the opposite feeling.

        We rail against the doublespeak /doublethink that pervades business and politics these days.

      • Apart from the incorrect generalisations that MB readers are fans of a corporatist/bureacratic state i agree that using tax to discourage concentrated fructose consumption is unecessary. However, if there was to be nanny tax, sugar would be a better target than fat.

  8. My understanding is there’s relatively little disagreement about vegetables and fruits being generally good for people. Hence subsidising fresh fruits and vegetables, as well as perhaps low calorie foods, would surely have a positive effect on health?

    • I was thinking along those lines too snag.

      If the substitution effect is a problem, why not tax all highly-processed foods, or as you suggest simply subsidise fresh foods (plus a tax incentive for home-grown/self-sufficiency perhaps? Or am I getting all utopian here…)

      The argument against carbohydrates (litterally any compound with the atoms C H and O in the ratio of 1:2:1) is a bit misleading. Simple sugars are not that great – I agree with the above posters on that front. However complex carbohydrates, wholegrain foods and low-GI carbohydrates (which also have higher fiber content) also get villified in this high fat, high protein, low carb love-fest.

      More leafy vegies (low calorie high nutrients), less protein from animal sources (read The China Study), and calories from complex carbohydrates is the healthier option. This is also less energy and water intensive than the high-fat/high-protein route.

      Then again I sympathise with the arguement that we really can’t afford to have a population all dying in their 80’s from chronic age-related (expensive) diseases. A few more abrupt heart failures at 65 might not be such a bad thing.
      Live hard, die young… For the grandkids?

  9. Travelling in Europe I’ve always been struck by how much smaller and richer (fattier) their serves are. Factor in more walking around, less stress, and there you have it- a better lifestyle.

    I think the commodification of food has led us to divorce it from any social and communal benefits. The industry now promotes constant dieting, combining sugar and fat in new and cheaper ways, or dressing up decent fresh produce as cuisine. If government wants to get involved they should just campaign with shocking ads showing the correlation btw obesity and the long list of life threatening illnesses.

  10. We could just hit the taxpayers on their individual BMI and give them carbon credits to partially offset it…

    • except that the BMI doesnt work at all, thats the problem with one size fits all approaches like this..

      for example at 5’10 and 100kgs im technically morbid according to BMI, throw in every rugby union/league player and anyone with muscle mass will be ‘taxed’, also anyone who uses a keto diet will be penalised under the no fat policy.

      Heres a radical idea… let people exercise some self discipline and responsibility and either pay or not pay for their actions instead of having to mother people down to what they put in their body..

  11. obviously it wasn’t an appropriate time for a gag then, my apologies.
    however, i think you are on to something with the taxing of league players…