In a latest research revealed in JAMA Community Open, researchers investigated whether or not implementing a tax on sweetened drinks was related to modifications within the physique mass index (BMI) of kids in Seattle.
Their findings point out that the tax was considerably related to a lower in BMI amongst youngsters residing within the Seattle space, suggesting that such taxes might successfully contribute to modest enhancements in youngsters’s BMI.
Research: Sweetened Beverage Tax Implementation and Change in Physique Mass Index Amongst Kids in Seattle. Picture Credit score: WH_Pics / Shutterstock
Background
Thus far, seven US cities have carried out excise taxes on sweetened drinks to enhance public well being by decreasing sugar-sweetened beverage consumption, the most important supply of added sugar within the US, and to generate income for different well being applications.
Earlier research have proven that these taxes improve beverage costs and cut back beverage purchases, doubtlessly reducing calorie consumption. Nonetheless, the connection between these taxes and self-reported sugary beverage consumption is commonly null, probably because of measurement difficulties and small research sizes.
Assessing well being outcomes stays essential as youngsters, who eat extra sweetened drinks, is perhaps extra affected by these taxes than adults.
Prior analysis on sweetened beverage taxes and youngsters’s BMI is proscribed and reveals combined outcomes: no affiliation in Mauritius, a discount in weight problems amongst adolescent women in Mexico, and a BMI lower amongst youngsters in three US cities.
In regards to the research
This research used longitudinal BMI knowledge from Seattle to look at the influence of taxes on youngsters’s BMI, hypothesizing decrease BMI positive aspects post-tax.
This cohort research included youngsters aged 2 to 18 who resided in city neighborhoods of three Seattle counties and acquired main care from two main hospitals or clinics between 2014 and 2019.
Contributors have been excluded if they’d most cancers, undergone bariatric surgical procedure, moved out of the research space, or had excessive BMI values.
The publicity of curiosity was the tax on sweetened drinks that was carried out in Seattle in early January 2018. Information on weight and top have been obtained from digital well being information, and BMI was calculated.
Researchers used BMIp95 (BMI as a share of the ninety fifth percentile for age and intercourse) because the research’s main final result.
The research used two statistical fashions: an artificial difference-in-differences (SDID) mannequin for kids with annual BMI measurements from 2015 to 2019 and a effective stratification common therapy impact (FSATE) weighted within-person change mannequin for kids with at the least one pre- and post-tax measurement.
Each fashions adjusted for confounders, with the first mannequin emphasizing pretreatment tendencies and individual-level fastened results. Analyses have been carried out utilizing Stata, with statistical significance set at α = .05.
Findings
The research’s main SDID mannequin comprised a pattern of 6313 youngsters (48% feminine and 52% male) with annual BMI measurements over 5 years, 28% of whom have been from Seattle and 72% from comparability areas.
On common, the contributors have been 7.7 years outdated, with a racial/ethnic composition of 13% Asian, 10% Black, 10% Hispanic, 50% White, and 11% of a number of races. The FSATE-weighted mannequin included 22,779 youngsters.
Outcomes confirmed that post-tax, Seattle youngsters had a extra important discount in BMIp95 in comparison with these in non-taxed areas, with an SDID estimate of -0.90 share factors (95% CI, -1.2 to -0.60).
The FSATE-weighted mannequin confirmed the same however barely bigger discount (β = -1.16 share factors, 95% CI, -1.91 to -0.41).
Subgroup analyses indicated constant reductions in BMIp95 throughout varied demographic teams, together with completely different ages, sexes, races, and insurance coverage sorts, notably amongst these with baseline obese.
Conclusions
The research concluded that the tax on sweetened drinks was correlated with a statistically important discount in youngsters’s BMIp95. This discovering aligns with earlier analysis, corresponding to research in Philadelphia, San Francisco, Oakland, and Mexico, which additionally reported reductions in youngsters’s BMI following beverage tax implementations.
The research’s strengths embody its use of longitudinal knowledge, measured heights and weights, and strong statistical strategies to regulate for pretax variations, thereby offering extra dependable proof than prior cross-sectional research.
Limitations of the research embody the shortage of direct knowledge on sweetened beverage consumption and the usage of medical information with restricted socioeconomic particulars. Moreover, whereas the SDID mannequin supplied internally legitimate estimates, it required all youngsters to have the identical variety of final result measurements, which lowered the pattern dimension and generalizability.
Regardless of these limitations, the research offers robust proof that taxes on sweetened drinks can present sensible coverage instruments to focus on BMI reductions in youngsters. Future research can discover this affiliation in different cities with related taxes to substantiate these findings.
Journal reference:
- Sweetened beverage tax implementation and alter in physique mass index amongst youngsters in Seattle. Jones-Smith, J.C., Knox, M.A., Chakrabarti, S., Wallace, J., Wilkinshaw, L., Mooney, S.J., Godwin, J., Arterburn, D.E., Eavey, J., Chan, N., Saelens, B. JAMA Community Open (2024). doi:10.1001/jamanetworkopen.2024.13644, https://jamanetwork.com/journals/jamanetworkopen/fullarticle/2819139
