Benefits and Risks of Baking Soda (Sodium Bicarbonate)
For Digestive Issues (Heartburn/Indigestion)
Baking soda can provide rapid symptomatic relief for occasional heartburn, but chronic use poses serious risks including metabolic alkalosis, electrolyte imbalances, and gastric rupture—particularly dangerous in patients with kidney disease who cannot excrete excess sodium and bicarbonate. 1, 2, 3
Mechanism and Acute Use
- Sodium bicarbonate neutralizes gastric acid quickly, providing temporary relief from acid indigestion 1
- For occasional use in healthy adults: ¼ teaspoon (approximately 1 gram) dissolved in water can be used, but this should not be repeated frequently 4
Serious Risks with Misuse
- Metabolic alkalosis develops when excessive bicarbonate overwhelms the body's buffering systems, causing pH elevation, hypokalemia, hypernatremia, and potentially respiratory depression 1, 2, 3
- Gastric rupture can occur from rapid CO₂ gas production when bicarbonate reacts with stomach acid 3
- Chronic use causes hypernatremia, hypertension, volume overload, hyporeninemia, and hypochloremia 3
- Abrupt cessation after chronic use may trigger hyperkalemia and volume contraction 3
High-Risk Populations Who Should Avoid Baking Soda for Heartburn
- Patients with kidney disease (GFR <60 mL/min/1.73m²): impaired renal excretion of sodium and bicarbonate dramatically increases toxicity risk 1, 2
- Pregnant women: at increased risk for complications 1
- Young children: higher susceptibility to electrolyte disturbances 1
- Patients with heart failure or hypertension: sodium load worsens fluid retention 3
- Those on chronic antacid therapy: cumulative toxicity risk 1
Clinical Pitfall
- A California Poison Control System review found 55.2% of baking soda misuse cases required medical evaluation, with 12 patients hospitalized for electrolyte imbalances, metabolic alkalosis, or respiratory depression 1
- Self-treatment delays appropriate medical care for potentially serious underlying conditions like peptic ulcer disease or gastroesophageal reflux disease 1
For Chronic Kidney Disease and Metabolic Acidosis
In CKD patients with serum bicarbonate <22 mmol/L, oral sodium bicarbonate supplementation is recommended to prevent protein catabolism and bone disease, but this indication requires medical supervision with specific dosing and monitoring—not over-the-counter baking soda use. 4, 5
Evidence-Based Indications
- The National Kidney Foundation recommends maintaining serum bicarbonate ≥22 mmol/L in dialysis patients to reduce protein degradation, preserve albumin synthesis, and prevent muscle wasting 4, 5
- For CKD patients with bicarbonate <22 mmol/L: oral sodium bicarbonate 0.5-1.0 mEq/kg/day divided into 2-3 doses 5
- Practical substitution: ¼ teaspoon of food-grade baking soda equals 1 gram (approximately 12 mEq) of sodium bicarbonate, but medical-grade tablets are preferred for consistent dosing 4
Monitoring Requirements
- Measure serum bicarbonate monthly initially, then every 3-4 months once stable 4, 5
- Check blood pressure, serum potassium, and fluid status regularly, as sodium load can worsen hypertension and volume overload 5
- Target bicarbonate: 22-26 mmol/L 4
Important Contraindications in CKD
- Do NOT use in severe acidosis from tissue hypoperfusion or septic shock—restore perfusion first 4, 5
- Do NOT use in diabetic ketoacidosis unless pH <6.9-7.0; insulin and fluids correct the underlying problem 4, 5
- Avoid citrate-containing alkali preparations in CKD patients on aluminum-containing phosphate binders due to increased aluminum absorption 5
Evidence Limitations
- A 2020 randomized trial (BiCARB RCT) of 300 patients aged ≥60 years with advanced CKD found that oral sodium bicarbonate did not improve physical function, quality of life, or renal outcomes compared to placebo, and was not cost-effective 6
- However, this trial achieved only small increments in serum bicarbonate, and benefits from higher doses or in patients with more severe acidosis (bicarbonate <18 mmol/L) cannot be excluded 6
For Oral Health
Baking soda in dentifrice rapidly neutralizes biofilm acids after sugar exposure, potentially preventing dental caries, especially in patients with reduced saliva production—but timing immediately after sugar intake is critical for effectiveness. 7
Mechanism of Benefit
- Sodium bicarbonate elevates dental biofilm pH above the critical demineralization threshold, favoring remineralization and preventing caries development 7
- Concentration matters: commercial dentifrices contain 10-65% baking soda, with higher concentrations showing better pH neutralization 7
Specific Populations Who May Benefit
- Patients with hyposalivation (dry mouth from medications, radiation, or Sjögren's syndrome) have diminished ability to clear sugars and buffer acids, making baking soda dentifrice particularly beneficial 7
- CKD patients on dialysis have xerostomia, elevated salivary pH, increased calculus formation, and poorer periodontal health—regular oral hygiene with baking soda-containing products may help 4, 8
Limitations
- Effectiveness depends on using baking soda dentifrice immediately after sugar exposure; delayed use provides minimal benefit 7
- More evidence is needed to confirm that pH modification strategies alter the cariogenic properties of biofilm microorganisms long-term 7
Critical Safety Summary
For patients with kidney disease (GFR <60 mL/min/1.73m²), baking soda should ONLY be used under medical supervision with specific dosing, monitoring, and clear therapeutic targets—never as self-treatment for heartburn or general wellness. 4, 5, 1, 2, 3