Substituting water for sugar-sweetened beverages reduces circulating triglycerides and the prevalence of metabolic syndrome in obese but not in overweight Mexican women in a randomized controlled trial

Abstract

Background: Mexico's sugar-sweetened beverage (SSB) intake is among the highest globally. Although evidence shows that increases in SSB intake are linked with increased energy intake, weight gain, and cardiometabolic risks, few randomized clinical trials have been conducted in adults.

Objective: The aim of this study was to determine if replacing SSBs with water affects plasma triglycerides (TGs) (primary outcome), weight, and other cardiometabolic factors.

Methods: We selected overweight/obese (BMI ≥ 25 and <39 kg/m(2)) women (18-45 y old) reporting an SSB intake of at least 250 kcal/d living in Cuernavaca, Mexico. Women were randomly allocated to the water and education provision (WEP) group (n = 120) or the education provision (EP)-only group (n = 120). The WEP group received biweekly water deliveries, and both groups received equal monthly nutrition counseling. During nutrition counseling, the WEP group sessions included activities to encourage increased water intake, reduced SSB intake, and substitution of water for SSBs. Repeated 24-h dietary recalls, anthropometric measurements, and fasting blood samples were collected at baseline and at 3, 6, and 9 mo. The Markov-Monte Carlo method was used for multiple imputation; separate mixed-effects models tested each outcome.

Results: An intent-to-treat (ITT) analysis indicated that the WEP group increased water intake and decreased SSB intake significantly over time, but there were no differences in plasma TG concentrations between groups at the end of the intervention (WEP at baseline: 155 ± 2.10 mg/dL; WEP at 9 mo: 149 ± 2.80 mg/dL; EP at baseline: 150 ± 1.90 mg/dL; EP at 9 mo: 161 ± 2.70 mg/dL; P for mean comparisons at 9 mo = 0.10). Secondary analyses showed significant effects on plasma TGs (change from baseline to 9 mo: WEP, -28.9 ± 7.7 mg/dL; EP, 8.5 ± 10.9 mg/dL; P = 0.03) and metabolic syndrome (MetS) prevalence at 9 mo (WEP: 18.1%; EP: 37.7%; P = 0.02) among obese participants.

Conclusions: Providing water and nutritional counseling was effective in increasing water intake and in partially decreasing SSB intake. We found no effect on plasma TGs, weight, and other cardiometabolic risks in the ITT analysis, although the intervention lowered plasma TGs and MetS prevalence among obese participants. Further studies are warranted. This trial was registered at http://www.clinicaltrials.gov as NCT01245010.

FIGURE 1

Flow of participants through the trial. ¹Phone screening criteria: age and reported BMI (confirmed at study site visit). ²Based on attendance at last appointment. EP, education provision; WEP, water and education provision.

FIGURE 2

Effects of the intervention at 9 mo on the basis of baseline weight status on plasma TG changes from baseline to 9 mo (A) and prevalence of metabolic syndrome at 9 mo (B). Values are means ± SEs (A) and percentages (95% CIs) (B). The model for panel A is a simple linear regression model including as an outcome variable the change in plasma TGs from baseline to 9 mo and as predictor variables the treatment group (WEP = 1, EP = 0) and BMI at baseline (obese = 1, overweight = 0). Interaction term: treatment × BMI at baseline; n = 184. The model for panel B is a logistic regression model, adjusted by prevalence of metabolic syndrome at baseline, treatment (WEP = 1, EP = 0), BMI at baseline (obese = 1, overweight = 0), change in physical activity from baseline to 9 mo, age at baseline, and interaction of treatment × BMI at baseline; n = 179. *Different from EP, P < 0.05. EP, education provision; WEP, water and education provision.