Bulletin of the World Health Organization

The effect of fiscal policy on diet, obesity and chronic disease: a systematic review

Anne Marie Thow, Stephen Jan, Stephen Leeder & Boyd Swinburn

Volume 88, Number 8, August 2010, 609-614

Table 2. Quality of the evidence in studies on the effects of fiscal policy on food consumption included in systematic literature review

Study type Individual study findingsa Notes on study quality
Experimental case-controlled study based on consumption data No studies Not applicable
Observational study based on individual consumption or household or sales data that investigated effects on the whole diet No studies Not applicable
Observational study based on individual consumption or household or sales data that investigated effects on the target food only Bahl et al.21 – tax decrease resulted in increased consumption Detailed model based on price and consumption data; included other influences on consumption; evaluated actual change in tax
Asfaw31 – subsidy decrease decreased obesity Simulation based on prices and price elasticity from historical survey data
Observational study based on population data Kim & Kawachi15 – states without a tax were more likely to have a higher relative increase in obesity Used BRFSS data; did not measure changes in consumption of taxed foods or beverages
Fletcher et al.41 – state tax increases had minimal effect Used BRFSS data; did not measure changes in consumption of taxed foods or beverages
Oaks43 – no relationship between tax and obesity rate Used BRFSS data; did not measure changes in consumption of taxed foods or beverages
Tefft37 – soft drink tax increase decreased consumption by a small amount Used aggregate expenditure data from a consumer expenditure survey and not the volume of consumption; did not measure changes in consumption of taxed foods or beverages
Predictive model based on individual consumption data that investigated effects on the whole diet Jensen & Smed22 – tax–subsidy combination improved diet Used annual aggregate consumption survey data
Mytton et al.30 – fat tax increased salt consumption; tax on less healthy foods improved diet and reduced CVD Used National Food Survey data and meta-analyses of the effect of dietary change on health.
Nnoaham et al.20 – tax alone increased CVD and cancer deaths, tax plus subsidy decreased deaths Used National Food Survey and Expenditure and Food Survey data and meta-analyses of the effect of dietary change on health.
Santarossa & Mainland23 – large fat tax decreased consumption Used food survey data; calculated tax rate based on dietary change desired
Predictive model based on household expenditure or food sales data that investigated effects on the whole diet Smed et al.24 – tax–subsidy combination improved diets; greatest effects in young people and those with a low socioeconomic status Used household purchase data
Allais et al.38 – tax on fatty foods decreased consumption and weight Used household purchase data
Predictive model based on individual consumption data that investigated effects on target foods only Cash et al.28 – fruit and vegetable subsidy decreased coronary heart disease Used consumption data from 1994–1998; relative disease risk based on panel surveys; 1999 and 2001 data were from different cohorts
Marshall29 – saturated fat tax decreased CVD deaths Used consumption data from dietary survey; price elasticity estimates not based on data
Farra et al.40 – soft drink tax reduced consumption and weight Simple calculation based on Irish price elasticity and USA sales data
Predictive model based on household expenditure or sales data that investigated effects on target foods only Chouinard et al.25 – high tax on dairy products resulted in minor decrease in fat consumption Used supermarket scanner data
Kuchler et al.26,27 – large taxes needed to decrease consumption Used household purchase data; used price elasticity estimates to simulate substantial price changes
Schroeter et al.32 – taxes and subsidies resulted in weight changes Used price elasticity data from the literature; no discussion of time over which apparent daily weight change is sustained
Dong & Lin33 – subsidy increased fruit and vegetable consumption Used household purchase data and NHANES data; only considered low-income Americans
Fantuzzi39 – tax had no effect on consumption Used supermarket scanner data; very high tax of US$ 9 per soft drink can
Gabe34 – soft drink tax reduced sales substantially Used sales and revenue data; only included two brands of soft drink and two sports drinks; assessed impact on the economy of Maine, USA
Gustavsen35 – large soft drink tax gave large decrease among heavy consumers Used consumption data from annual household survey; considered difference in price elasticity with consumption volume
Nordström & Thunström36 – large subsidy plus tax improved diet Used household expenditure data; used price elasticity estimates to simulate substantial price changes
Predictive model based on the association between observed price data and BMI Gelbach42 – large tax on unhealthy foods reduced overweight and obesity Used National Health Interview Survey and price data; used price elasticity estimates to simulate substantial price changes

BMI body mass index; BRFSS, Behavioural Risk Factor Surveillance Survey; CVD, cardiovascular disease; NHANES, National Health and Nutrition Examination Survey; USA, United States of America; US$, United States dollar.

a Unpublished studies are shown in italics.