Evaluating the Evidence on Beverage Taxes: Implications for Public Health and Health Equity
Year: 2022
Type: article
Abstract: Sugar-sweetened beverage (SSB) taxes have taken off, as evidenced by their implementation in more than 45 countries and several local jurisdictions.In a short time, a large literature has amassed, which Andreyeva et al 1 systematically reviewed and meta-analyzed to inform worldwide tax policy.Not surprisingly, they report that SSB taxes, on average, were associated with significantly higher prices, with 82% of the tax passed through to prices.They also found that these taxes were associated with an average 15% decrease in SSB sales, estimating the price elasticity at -1.59.These sales results were based on 35 estimates from 33 generally high-quality studies that used large data sets with objective measures and little missing data.Perhaps surprisingly, they did not find overall evidence of substitution to sales of untaxed beverages, although some tax evaluations do show this.When such substitution is not observed, it could mean consumers replace SSBs with tap water or do not replace them at all.The studies in the review by Andreyeva et al 1 included evaluations of volume-and sugarbased taxes, different tax amounts and types (excise, sales), diverse populations across many countries and local jurisdictions, and different store types.Although effect size estimates were heterogeneous across these characteristics, the bottom line is the same: SSB taxes are associated with sustained reductions in SSB sales.This kind of sustained behavior change is a highly elusive outcome for dietary interventions.The authors additionally found an 18% decline in SSB consumption with a 95% confidence interval that just crossed the null (P = .07).The point estimate is very similar to that of the sales analysis but much less precisely estimated because of small sample sizes and because consumption measures tend to be far noisier than sales data.Moreover, 75% of the consumption studies were deemed low-quality, and the meta-analysis of the consumption data only included the low-quality studies, excluding 4 medium-quality studies because of missing data.Larger, higher-quality studies of posttax consumption are needed.For example, a recent US study of 86 928 nationally representative adolescents using a difference-in-differences design reported a decrease of 0.81 servings per week (-15% of baseline consumption) following the Philadelphia tax. 2 A beverage tax's impact on SSB consumption can be diminished, however, based on tax design.For example, city-level taxes can induce some individuals to shop across the tax jurisdiction border, which offset a significant proportion of sales declines in several studies.Tax advocates recommend passing SSB taxes at the national or state level to reduce the likelihood of tax avoidance.Additionally, some consumers may substitute SSBs for liquid and powder beverage concentrates, which are excluded from most taxes even though they are used to make sugary drinks.This kind of substitution has been observed in response to some taxes, 3 but few studies have examined this possibility, making it an important question for future research.The authors describe weak evidence for the association between taxes and BMI, but there is an important caveat.Although all the studies assessing BMI were deemed medium-quality, all evaluated older sales taxes rather than more recent excise taxes.Compared with excise taxes, sales taxes have resulted in smaller price increases and are not incorporated into prices at the point of purchase-they appear on the receipt after purchase, making them less likely to influence behavior.It is still too early to evaluate posttax changes in weight for most current excise taxes given the multifaceted drivers of metabolism and weight gain.Some recent work, however, shows that Mexico's SSB tax was +
Source: JAMA Network Open
Language: English
Domain: Social Sciences
Open Access status: gold
Estimated APC paid: $3,000
OpenAlex ID: W4281771929