A pinch of baking soda for better sight?

A pinch of baking soda can help people see better by modifying the visual signal generated by photoreceptors in the eye that detect light, say researchers.

Much of the bicarbonate (baking soda) in our bodies comes from carbon dioxide which is produced as a waste product in all cells, although some is ingested with carbonated beverages and certain types of foods.

In a paper that appeared in the Journal of Biological Chemistry, the team from the Makino Laboratory at Massachusetts Eye and Ear/Harvard Medical School and Pennsylvania-based Salus University described that controlling bicarbonate levels in the eye will slow the progress of -- or may even prevent -- eye diseases.

Bicarbonate (baking soda) makes sparkling water sparkle, causes bread to rise, absorbs odours and can be used for cleaning all sorts of stuff, including your teeth.

In the body, it plays essential roles in buffering pH levels, aiding in digestion and neutralising lactic acid produced during physical exertion.

Within rods and cone photoreceptors, a small soluble molecule called cGMP links photon absorption to the electrical activity of the photoreceptor.

In the light, cGMP is destroyed and ion channels are closed.

"By opposing the effect of light, bicarbonate limits the size of the photon response and quickens its recovery. As a result, sensitivity to light is slightly lower but our ability to track moving objects is improved," said lead author Clint Makino, director of the Makino laboratory.

It is known that in some types of retinal diseases, a genetic defect causes cGMP in the rods and/or cones to rise to abnormally high levels.

Once lost, rods and cones are not replaced, so an irreversible blindness is the tragic outcome.