Lactic acid is buffered mainly by what?

The main buffer for lactic acid in the body is the bicarbonate buffer system. This system consists of carbonic acid (H2CO3) and bicarbonate ion (HCO3-), which can react with lactic acid (CH3CH(OH)COOH) to form water (H2O) and carbon dioxide (CO2).

The reaction scheme is as follows:

Lacitc acid + Sodium bicarbonate ⇌ Sodium lactate + Carbonic acid

Carbonic acid ⇌ Water + Carbon dioxide

This reaction helps to maintain the pH of the body fluids by preventing the lactic acid from causing too much acidity. The bicarbonate buffer system is also important in regulating the acid-base balance of the blood.