Findings from the STOP Sugars NOW Trial

Study Finds Low- and No-Calorie Sweetened Beverages Perform Similar to Water in Replacing Sugary Drinks

Findings from the STOP Sugars NOW Trial show no impact on the gut microbiome when sugar-sweetened beverages are replaced with low- and no-calorie sweetened alternatives.

Study Design Overview

This single-center, open-label, multiple-crossover randomized controlled trial evaluated the effects of replacing sugar-sweetened beverages with either low- and no-calorie sweetened beverages or water in overweight and obese individuals at risk for cardiometabolic disease. Over four weeks, researchers assessed impacts on glucose tolerance, gut microbiome diversity, and other intermediate cardiometabolic health outcomes across three clinically and publicly relevant comparisons.

  1. LNCBs for SSBs (“intended substitution” with energy displacement)
  2. Water for SSBs (“standard of care substitution” with energy displacement)
  3. LNCBs for Water (“reference substitution” without energy displacement)

Primary Outcomes

Although there are concerns that low- and no-calorie sweeteners (LNCSs) may induce changes in glucose tolerance through the microbiome, the STOP Sugars NOW trial did not show this effect. Researchers found that low- and no-calorie sweetened beverages (LNCSBs), sweetened predominantly with a blend of aspartame and ace-k, did not negatively affect either of the two primary outcomes in ITT analyses. These outcomes included changes in gut microbiome beta-diversity and glucose tolerance. Results were similar when comparing LNCSBs replacing sugar-sweetened beverages (SSBs) and water replacing SSBs.

Adherence appears to be a determinant of any effects. Completers and per protocol analyses showed that the substitution of LNCSBs for SSBS (the “intended substitution” with caloric displacement) and water for SSBs (the “standard of care” without caloric displacement) improve fasting plasma glucose and liver fat (sub-study) with water showing greater reductions.

Findings Align with Existing Evidence

This data is consistent with the available RCTs which have failed to show any effect on microbiome and glucose tolerance. It also supports clinical practice guidelines recommending LNCSBs as an alternative strategy to the “standard of care” water for SSBs reduction.

Key Takeaway

Replacing sugar-sweetened beverages with low- and no-calorie sweetened beverages produced effects similar to water, with no significant impact on gut microbiome diversity or glucose tolerance in overweight and obese individuals.

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