Exploring a fiscal food policy: the case of diet and ischaemic heart disease
Extending value added tax (VAT) to foodstuffs which are high in saturated fat, could save between 900 and 1000 premature deaths a year in the UK, suggests Dr Tom Marshall from the University of Birmingham in this week's BMJ.
In his education and debate article Marshall considers the impact that diet has on cholesterol concentrations in the UK population (which in turn determines the prevalence of ischaemic heart disease). He says that cholesterol concentrations are largely down to the proportion of dietary energy derived from saturated or polyunsaturated fats and by dietary intake of cholesterol and that if this were reduced then there would be a fall in the number of people suffering from ischaemic heart disease.
Marshall identifies the main sources of saturated fat in the British diet as whole (full fat) milk, cheese, butter, biscuits, buns, cakes, pastries, puddings and icecream. He says that currently, the pricing of foodstuffs encourages the purchase and consumption of a cholesterol raising diet, particularly among people who have a tight food budget. At the moment, most foodstuffs are exempt from VAT, states the author. However, if VAT were to be extended to the principal sources of dietary saturated fat, while exempting cholesterol neutral foods, he suggests that the public would purchase the cheaper, lower fat alternatives. He believes that this would have the greatest effect among lower income groups who tend to be more price sensitive and are at greatest risk of ischaemic heart disease from poor diet. [The author extensively explains the concept of price elasticity in his paper.]
The author says that the concept he proposes is similar to the "polluter pays" principle of making leaded fuel more expensive than unleaded. The additional tax revenue generated through such an initiative could be used to finance compensatory measures to raise the income of low income groups, suggests Marshall as these groups will inevitably end up paying more for their food bills under such a system (just as by raising the duty on tobacco the group that bears the tax burden is in the low income bracket). The overall effect on government finances would therefore be neutral, he says.
The author concludes that if we are serious about improving nutrition a fiscal food policy is "worth exploring". "Interdisciplinary collaboration is needed between econometricians and nutritionists to investigateŠthe effects of price changes on the purchase of foodstuffs," he says.
In an accompanying commentary Dr Eileen Kennedy and Dr Susan Offutt from the US Department of Agriculture write that Marshall's concept is intriguing, but they raise doubts as to how successful such an approach would be. Firstly, the relation of diet and disease hinges on an individual's genetic make-up which is not accounted for in Marshall's hypothesis. Secondly, Kennedy and Offutt highlight recent research suggesting that the substitution of lower fat foods (such as skimmed milk for full fat milk) simply results in an approximate doubling of the quantity of the lower fat alternative consumed, in order that energy levels are maintained in the diet.
Kennedy and Offutt also question Marshall's statement that there is a sizeable difference in the diets of the rich and poor - they say that in the United States at least, this is not true. They also argue that price sensitivity to the main sources of dietary fat is not as great as Marshall has suggested and therefore an extension of value added tax would lead to smaller decreases in quantities consumed.
The authors of the commentary conclude that a better alternative to extending VAT would be to introduce foodstuffs which help to reduce cholesterol but that do not require a change in consumer dietary behaviour.
Contact:
Dr Tom Marshall, Honorary Clinical Lecturer, Department of Public Health and Epidemiology, University of Birmingham, Birmingham
Tel: +44 (0)121 414 7422 (not available Thursday morning)
Email: marshatp@hsrc1.ac.uk
Dr Eileen Kennedy, Deputy Under Secretary, Office of Research, Education and Economics, US Department of Agriculture,
Washington
Email: eileen.kennedy@usda.gov