Gastrointestinal Symptoms Associated With Sodium Bicarbonate Supplementation Protocols: A Systematic Review

Area of Science:

• Sports Science
• Nutritional Biochemistry
• Gastroenterology

Background:

• Sodium bicarbonate is a known ergogenic aid.
• Gastrointestinal symptoms (GIS) are a common side effect limiting its use.
• Understanding GIS mitigation strategies is crucial for athletes.

Purpose of the Study:

• To systematically review and synthesize existing literature on GIS associated with sodium bicarbonate supplementation.
• To evaluate the effectiveness of different dosing strategies and forms in reducing GIS.
• To identify gaps in current research regarding GIS management.

Main Methods:

• Systematic literature search conducted from February 2024 to March 2026.
• Included studies involving sodium bicarbonate supplementation (≥ 5g/24h) with a placebo or comparison group.
• Categorized 101 investigations into dosing protocols (acute, chronic), delivery forms, and other factors.

Main Results:

• Acute doses (0.2-0.4 g/kg) commonly cause mild-to-severe GIS, potentially dose-dependently.
• Strategies like spread dosing, enteric coating, and mini-tablets may reduce GIS, but direct comparisons are lacking.
• Multi-day dosing might reduce GIS, though symptom reporting is often inadequate. Many studies lacked statistical analysis for GIS differences.

Conclusions:

• Definitive recommendations for minimizing GIS with sodium bicarbonate are challenging due to insufficient comparative data.
• Further research is needed for direct comparisons of GIS-reducing protocols.
• Improved data collection, reporting, and analysis of GIS are essential for future studies.