Sodium bicarbonate (0.3 g/kg body mass) and its combination with glycerol significantly elevate blood pH and bicarbonate concentration by 0.06–0.07 pH units and 7.1–7.2 mmol/L above baseline at 180 minutes post-ingestion in healthy adults, indicating enhanced blood buffering capacity.

When sodium bicarbonate is swallowed, it breaks down into sodium and bicarbonate ions. The sodium pulls water into the bloodstream by increasing the salt concentration, which tells the kidneys to hold onto more water instead of peeing it out. The bicarbonate ions enter the blood and neutralize excess acid, making the blood less acidic and better able to absorb more acid later. Glycerol does the same thing with water by increasing salt concentration, and when taken with sodium bicarbonate, it makes the water retention start faster without making it any stronger.