TABLE 1.

Sugar taxation & restriction studies

Author, Year	Study population	Study design	Intervention	Main findings
Sugar taxation studies with SSB consumption–focused outcomes
Colchero et al, 2016126	6253 households in 53 cities in Mexico	Observational study using data from Nielsen Mexico’s Consumer Panel Services on the purchase of beverages in Mexico from January 2012 to December 2014	Excise tax of 1 peso/L on SSB	Purchase of taxed beverages decreased by an average of 6% and at an increasing rate of up to a 12% decline by December 2014. Reductions are higher among households of low SES.
Falbe et al, 2016127	Low-income neighborhoods in Berkeley vs. the comparison cities of Oakland and San Francisco, California	Repeated cross-sectional study to examine changes in pre-tax to post-tax beverage consumption based on data from an interviewer-administered beverage frequency questionnaire	Excise tax ($0.01/oz) on SSB	Consumption of SSBs decreased by 21% in Berkeley and increased by 4% in comparison cities (P = .046). Water consumption increased more in Berkeley (+ 63%) than in comparison cities (+ 19%; P < 0.01).
Sugar restriction studies with liver health–focused outcomes
Schwarz et al, 2017116	41 nondiabetic Latino and African American children (9–18 y) with obesity and metabolic syndrome, who identified as having habitual high sugar consumption (fructose intake >50 g/d)	Convenience cohort within-subject intervention with repeated measures	Meal provision restricting fructose ingestion only to naturally occurring fructose in fruits and vegetables (~ 15 gm/d/ 4% of total kcal, for 9 d) by substituting complex carbohydrates for excess dietary fructose while maintaining a neutral energy balance	Liver fat decreased from a median of 7.2% to 3.8% (P < .001). VAT decreased from 123 cm3 to 110 cm3 (P < .001). The DNL AUC decreased from 68% to 26% (P < 0.001). Insulin kinetics improved (P < 0.001). Changes occurred irrespective of baseline liver fat.
Schwimmer et al, 201933	40 adolescent boys with biopsy-confirmed NAFLD, ages 11–16 y	Randomized, parallel assignment clinical trial without blinding	8-week LFSD: Individualized menu planning and meal provision for the entire household to restrict free sugar intake to less than 3% of daily calories	Mean decrease in hepatic steatosis from baseline to week 8 was significantly greater for the intervention diet group (25%–17%) vs. the usual diet group (21%–20%), and the adjusted week 8 mean difference was −6.23% (P < 0.001).
Cohen et al., 202167	40 adolescent boys with biopsy-confirmed NAFLD, ages 11–16 y	Randomized, parallel assignment clinical trial without blinding	8-week LFSD (see Schwimmer et al., 2019, 2019 above) + 7-day metabolic labeling protocol with heavy water	Hepatic DNL was significantly decreased in the treatment group (from 34.6% to 24.1%) vs. the control group (33.9%–34.6%), along with greater decreases in hepatic fat and fasting insulin.
Cohen et al., 2023132	40 adolescent boys with biopsy-confirmed NAFLD, ages 11–16 y	Randomized, parallel assignment clinical trial without blinding	8-week LFSD (see Schwimmer et al., 2019 above) + plasma metabolomics analysis	The LFSD treatment, compared to the usual diet, was associated with differential expression of 419 metabolite features (P < 0.05), which were enriched in amino acid pathways, including methionine/cysteine and serine/glycine/alanine metabolism (P < 0.05), and lipid pathways, including omega-3 and linoleate metabolism (P < 0.05).Microbiome changes included an increase in richness at the phylum level and changes in a few genera within Firmicutes.
Schmidt et al, 2022133	105 Latino adolescents (11–18 y) with obesity (BMI ≥95th percentile for age & sex)	Parallel-design randomized controlled dietary intervention trial	A 12-week dietitian-led sugar reduction intervention, including nutrition education to promote free sugar reduction to ≤ 10% of total calorie needs	Mean free sugar intake decreased in the intervention group vs. control (11.5%–7.3% compared with 13.9%–10.7% of total energy needs, respectively; P = 0.02). There were no significant effects on liver outcomes or anthropometrics (P all > 0.10).
Kord-Varkaneh et al, 2023134	52 overweight/obese adults with NAFLD, ages 18–50 y	Randomized clinical trial	A 12-week time-restricted feeding intervention (16 h fasting/8 h feeding daily) + a low-sugar diet (< 3% total energy needs)	The time-restricted feeding intervention group reduced body fat, body weight, WC, BMI, fasting blood glucose, liver enzymes (ALT, AST, GGT), lipids (TG, TC, LDL-cholesterol), and inflammatory markers (hs-CRP and cytokeratin-18), all statistically significant vs. control (P<0.05).
Khodami et al, 2022134	43 overweight/obese adults with FibroScan-proven NAFLD, ages 18–60 y	Randomized two-arm, parallel dietary intervention	12-week LFSD intervention (dietitian instruction to limit free sugars to <10% of total energy needs)	The LFSD intervention group compared with the usual diet control group, significantly decreased ALT, TG, TC, FBS, insulin, HOMA-IR, hs-CRP, TNF-α, and NF-kb (P < 0.05). The LFSD group also reduced fibrosis score and steatosis score, with increased QUICKI compared to the control (P < 0.05).
Mager et al., 2015136	Children and adolescents with NAFLD (n = 12) and healthy controls (n = 14), ages 7–18 y	Prospective dietary intervention	Dietary education/sample menus to promote the consumption of a low fructose (< 7% energy needs) and low glycemic index (45–55)/glycemic load (< 80) (FRAGILE) diet over 6 mo	In children with NAFLD, there were significant reductions in SBP, percentage BF, and plasma concentrations of ALT (P = 0.04), Apo-B-100 (P < .001), and HOMA-IR at 3 and 6 mo (P < 0.05). Dietary reductions in fructose and GL were related to reductions in SBP (P = 0.01), ALT (P = 0.004), HOMA-IR (P = 0.03), and percentage BF. No changes in laboratory variables were observed in the healthy control group except for Apo-B-100.

Abbreviations: ALT, alanine aminotransferase; Apo-B-100, apolipoprotein B-100; AST, aspartate aminotransferase; BF, body fat; BMI, body mass index; DNL, de novo lipogenesis; FBS, fasting blood sugar; GGT, gamma-glutamyl transferase; GL, glycemic load; HOMA-IR, Homeostatic Model Assessment for Insulin Resistance; hs-CRP, high sensitivity C-reactive protein, TG, triglycerides; LFSD, low free sugar diet; QUICKI, quantitative insulin sensitivity check index; SBP, systolic blood pressure; SSB, sugar-sweetened beverages; TC, total cholesterol; VAT, visceral adipose tissue; WC, waist circumference.