★★★★☆
A coated tongue reflects what's going on in the digestive tract -- either poor digestion (for example, poor digestion of fats), or a bacterial or fungal infection. Glycerin may be 'cleaning' the tongue coating, but is it really doing anything to correct the cause of the problem? My guess is if one stops with the glycerin, and the tongue coating comes back, then the answer is "no". ???
