Published in January 2007 issue of Prospect Magazine
Eat, drink and be merry
According to the department of health’s recent report on obesity in England, a staggering 4.3m men and 4.7m women aged over 16 were classified as obese in 2003—22 and 23 per cent respectively of the total population. Another excuse for the busybodies to lecture people on how they must behave?
A person is classed as obese if his or her body mass index (BMI) is over 30. BMI is calculated by dividing the body weight in kilos by the square of the height in metres. So a six-foot-tall person has a BMI of 30 at a weight of 15 stone 11 pounds (100 kilos for younger readers). While substantial, this is not the build of a sumo wrestler. And the formula takes no account of the composition of body weight. Keiron Cunningham, the St Helens and Great Britain rugby league star, is 5 foot 9 inches and weighs 16 stone 9 pounds, so is grossly obese according to his BMI (34.5). But fat he is not.
How are the figures arrived at? The recording of patients’ BMIs is done by GPs, and reported at the level of the 300-plus primary care trust areas. It is claimed that almost 30 per cent of GP-registered people aged 15-75 have had their BMI measured. But there are big variations: in the Easington area, GPs claim that over 99 per cent of people on their books have been measured, while in Kennet and West Wiltshire the figure is less than 3 per cent. Moreover, department of health figures rather implausibly suggest that in rich northeast Oxfordshire and southwest Oxfordshire, everyone is obese, while in poor east Hull less than 4 per cent are.
In a paper in the September issue of the American Economic Review, two economists from University College London, Jérôme Adda and Francesca Cornaglia, examine the impact of taxes on cigarette consumption. Not surprisingly, the US states with higher taxes are associated with lower sales of cigarettes. But smokers compensate in two ways. First, they switch to cigarettes with a higher tar and nicotine yield. Second, the intensity with which any given cigarette is smoked increases. The paper therefore questions the usefulness of excise taxes as a tool to regulate smoking intake. It also suggests that the effects of passive smoking are grossly exaggerated. Smokers on average had a level of cotinine (a marker of nicotine intake) no less than 520 times higher than non-smokers. In addition, the authors shed light on a puzzle. African-Americans smoke slightly less than white Americans, but their lung cancer rate is much higher, at about 120 per 100,000 compared to 79 for whites. It turns out that they smoke more intensely, extracting on average a huge 56 per cent more nicotine per cigarette than their white fellow addicts.