The impact of trans fat regulation on social inequalities in coronary heart disease in Australia

To the Editor: The evidence that industrially produced trans fatty acids (TFAs) increase the risk of coronary heart disease is compelling, and it is widely agreed that their use in food products should be minimised.1-3 Dietary TFAs are generally found in higher quantities in “unhealthy” food products,4 consumption of which is also found to follow predictable socio-demographic patterns.5 Thus, although the average TFA intake for Australians is relatively low, socioeconomically disadvantaged people are likely to disproportionately represent those with above average intakes.

Mandatory labelling of TFA content on all packaged foods in Australia has recently been advocated,1 so that individuals can make informed decisions about purchasing products with excessive levels of TFA. However, while such an intervention may reduce TFA intake at the population level, it is likely to increase social inequalities in TFA consumption and, therefore, inequalities in deaths from coronary heart disease. The reasons for this are as follows. First, research has shown that people who have healthier diets and who are from higher socioeconomic backgrounds are more likely to seek out and use food labels to make healthier choices,6 while those from more disadvantaged backgrounds who do not understand or act on nutrient labelling are much less likely to benefit. Second, mandatory TFA labelling may prompt food manufacturers to brand their products as “TFA-free”, which may bestow an undeserved “health halo” on energy-dense nutrient-poor foods.3 This “health halo” effect is likely to disproportionately influence the purchasing decisions of lower socioeconomic groups, among whom nutrition knowledge tends to be lower than among higher socioeconomic groups.4,5

The ability to replace industrially produced TFAs with healthier alternatives at minimal expense to consumers has prompted jurisdictions such as Denmark and New York City to introduce mandatory limits on the total amount of TFA permitted in all food products. Recent evaluation of the New York City policy showed a significant reduction of TFA in restaurant products, without a corresponding increase in saturated fat, and this effect was similar across high-income and low-income neighbourhoods.7

It is time that Australia introduced strong regulation to reduce TFA intake for all Australians.