nutrition and health
Bicarbonate is naturally produced by the gastric membrane in the stomach. This production will be low in alkaline conditions and will rise in response to acidity. In healthy individuals this adaptive mechanism will control the pH perfectly. Thus bicarbonate may be helpful for digestion by reducing the acidity of dietary components.
An important effect of bicarbonate ingestion is the change in acid-base balance and blood pH.
Some research has shown that the consumption of sodium bicarbonate (an alkalizing agent) helps to buffer the lactic acid concentration in the bloodstream. The decrease in blood acidity would in turn allow the acid within the cells to enter the blood stream via the concentration gradient. Bicarbonate is not able to enter the cells; therefore it must act in the bloodstream.
The expression "lactic acid" is used most commonly by athletes to describe the intense pain felt during exhaustive exercise. The normal pH of the muscle cell is 7.1 but if pH is reduced to around 6.5 due to lactic acid build up, then muscle contraction may be impaired and the low pH will stimulate the free nerve endings in the muscle resulting in the perception of pain (the burn). This point is often measured as the lactic threshold, anaerobic threshold or onset of blood lactate accumulation.
