Glycolic acid can be produced in the lab by reaction of chloro-acetic acid with sodium hydroxide followed by re-acidification, it is also found in some natural sources as sugarcane, pineapple and unripe grapes. What makes Glycolic acid a frontrunner for skin care products is its excellent capability to penetrate skin and peels of the old skin by weakening the binding power of lipids which hold the dead skin cells together in the upper layer of the epidermis (top part of the surface skin).This allows new live skin cells to be exposed and gives one’s skin a bright new texture.
Now coming to your question of is usage.it has been found that using the Glycolic acid face wash twice is sufficient. The thing you need to take care of is now to be around polluted surroundings after using it. Normally it is advisable to use it after waking up and before going to sleep. The important one amongst these is before going to bed, the reason being you are not prone to air pollutants. If you live in a pollutant free environment during the day like office or inside buildings you can use it during the lunch break as well.
The diet doesn’t have much of a direct relation but try not to have oily or spicy food as the more oily food you eat the more you skin is bound to secrete.an additional advice is that Glycolic acid is a strong irritant and can metabolize to oxalic acid if ingested so be careful during its use that no part of it is accidently injected.
