Archive for the ‘Obesity’ Category

The effects of cigarette costs on BMI and obesity

Two obesity posts in one day. This is another paper from the Health Economics RSS feed. The effects of cigarette costs on BMI and obesity, by Charles Baum (Middle Tennessee State University).

About 30% of Americans are currently obese, which is roughly a 100% increase from 25 years ago. Public health officials have consequently become alarmed because recent research indicates that societal costs of obesity now exceed those of cigarette smoking and alcoholism. Cigarette taxes may have exacerbated the prevalence of obesity. In 1964, the US Surgeon General issued its first report relating smoking and health, and since that time, federal and state governments have increased cigarette taxes in a successful effort to reduce cigarette smoking. However, because cigarette smoking and obesity seem inversely related, cigarette taxes may have simultaneously increased obesity.

This paper examines the effects of cigarette costs on BMI and obesity and finds that they have significant positive effects. This paper attempts to reconcile conflicting evidence in the literature by controlling more carefully for correlation with state-specific time trends using panel data.

Results indicate that the net benefit to society of increasing cigarette taxes may not be as large as previously thought, though this research in no way concludes that they should be decreased to prompt weight loss.

That’s some caveat (the italics are the author’s). I’d like to write a paper requiring that sort of defence mechanism, one day.

The problem:

Baum figure 1

Baum figure 2

USA Today’s coverage of the Mississippi Dumb Obesity Bill even had a map:

cdc pic

That’s the geo-location of obesity in the US, according to the CDC. What isn’t already phenomenally expensive for the State is mopped up by you – Americans are spending some USD30bn (USD41bn in today’s dollars) on weight-loss wastes of time.

So to Charles Baum and his paper (BYO Orchestra – sorry). His paper argues that taxation on cigarettes contains a heretofore hidden opportunity cost/unintended consequence: cigarettes, as diet-suppressants, are a pathway to non-obesity (for want of a better description). There is a social gradient to cigarette-smoking (poor people do it more) and to obesity (poor people are it more, for a variety of income-related reasons). Increasing cigarette prices (Healthy People 2010, for example, wants taxation to be USD2 per pack – a nearly 100% increase) will therefore have some effect on decreasing the quantity of cigarettes demanded – it will also (according to Baum) have a subsequent effect on obesity.

Controlling for a bundle of covariates (not reported: click for a larger image):

Baum table 3

We see our outcome. The models, spread across several tables, are, however, quite unstable (in that the results are very sensitive to specification), so there is a significant residual question over the value of the information we’re receiving here. Frequentistedly (I made that up) we observe statistical significance, but my Bayesian switches all flipped with these results. I’m not convinced even by the descriptive statistics that suggest heterogeneity amongst obesity and cigarettes prices/taxes: there are just too many state and environmental variables (I think – although he does control for these in the regression analysis).

One of the things that I didn’t see mentioned in this paper was the effect on smoking intensity. The impact of cigarette taxation not only on consumption but on intensity is known – it is the intensity, for example, that contributes a great deal to the carcinogenic effect of smoking.

I would expect, then, that the compensating increase in smoking intensity would also have an affect on BMI and obesity according to the Baum models, but such a confounder was not mentioned. It seems that, instead, a linear relationship is assumed between the consumption of cigarettes and the intensity with which they are smoked, rather than the more likely concave function.

Amongst other things this, if significant, negates the entire argument that Baum is trying to make. The kindness of tax increases is questioned precisely because the increase in intensity is more harmful: would the same increase in intensity not also leave BMI either unchanged, or at least changed in an unkown direction? Getting back to the sensitivity of the results to model specification – this would explain a lot of that. The actual intake of nicotine, etc. per smoker is simply not being measured, but we know that it is not constant; nor is it linearly-determined by either cigarette consumption or cigarette prices.

It’s an interesting idea. I think the paper is missing some critical pieces, but it’s certainly an interesting policy angle to examine.

And pile all those history books, but don’t throw them away/They just might have a clue about what it really means/To be an Anglo hyphen Saxon in England.co.uk

Bloody interesting article by Rafael Behr in Today’s Guardian.

In it he discusses the nature of identity – specifically the fact that, in the anglo majority, the culture is your identity. Unlike an immigrant, for whom private and public personae are likely the norm and where the private identity, based upon your origin, functions existentially as a security blanket. We (the anglo majority; I’m not joining up with O’Reilly and Mad Man McCain or anything) do not have this. We are supposed to be, within our homes, that which we are outside our homes.

I would say I’m among the exceptions to this. Being Australian in the US, vegan, Buddhist (opinions differ), etc. adds me up to not-the-norm (I’m told often enough that I also hate America). Certainly in terms of the obesity question, which is that at which Behr is getting:

The result is a sort of cultural insecurity among the majority, non-immigrant British. If you are an immigrant and also a UK citizen, the chances are you have dual identity. Let’s say for the sake of argument you are Muslim and British. The split in your identity probably coincides with a split between public and private personae. At work, in the shops, in the street you are British. At home, around the dining table, you are Muslim. When the world outside your front door is a bewildering, insecure, chaotic global marketplace, your private cultural identity isn’t a luxury, it is an existential necessity. It keeps you sane.

If, however, you are part of the overwhelming majority of white, non-devout Christians, no such cultural safety net exists. Your culture is the mass culture, which is global consumer culture, which is no culture at all.

That matters in the fight against obesity. A cultureless society eats primitively, consuming the worst kind of foods, high in saturated fats, refined carbohydrates, sugar, salt. There is a reason mankind likes this sort of food. It is a legacy from our troglodyte ancestors for whom energy-yielding foods could guarantee survival in a hostile environment

The development of more sophisticated tastes is part of the process of civilisation. Millions of Britons now have an uncivilised approach to food. Go to any high street and count the people shovelling cakes in their mouths with feral urgency. We eat like cavemen.

I see this through a US lens – just yesterday I was impressed with the number of vendors hawking Father’s Day (that was yesterday in US – crazy, isn’t it? Everyone knows God made Father’s Day the 1st Sunday in September). This included wine-sellers (celebrate Father’s Day with wine-tasting? I just don’t see it). America loves a holiday, and every year I see not only Establishment Holidays (for want of a better word) getting bigger, but smaller holidays. Like Halloween in Britain, which Behr discusses, there is very obvious market interest in expanding holidays, particular ones with special consumer-behaviour attached (Halloweeen makes an excellent case in point. July 4th is a ‘day’ here, now a holiday, and one that seems to be evolving into a proper establishment holiday. I already hear “Happy July 4th”, and I expect cards and gifts can’t be far off?).

I don’t know what it’s like in Australia – we have so many public holidays there is probably overkill keeping the festival-ness of them down. Plus you get a day off, you stick an international cricket match in it. Everybody knows that’s the natural order of things. Our Australia Day is not and probably will never be celebrated like July 4th – it’s more like Columbus day, which Universities only call a ‘pacing break’, rather than offend.

Behr’s point about food and the manner in which we eat it is a good one, although I suspect he’s premature in the rescue of immigrant Britain. Non-immigrant Britain has fallen victim to the move of production from households to Tescos, but why it should stop there cannot be adequately presented. As sure as they work long hours, watch TV and want convenient food, so shall it be made for them, whoever ‘they’ are. If the pattern breaks because of greater awareness, all the better, but health-economic research in enough countries suggests it might not be enough.

Meanwhile, Brits, you will be pleased to know that your deep-fried pizzas are nothing.