What would a holistic doctor or asian/eastern medicine doctor say is the reason for a phlegmy tongue? i don't smoke and drink little caffeine??

They say there is: many different coughs and diagnoses for tongue phelgm depending on yin deficiency or excess, yang deficiency or excess, or triple warmer excess, liver heat rising, damp heat, damp cold & then combine it with pulse analysis & heart findings (stethoscope too) to arrive at a diagnosis. Basically,it's a system in itself that complements chronic conditions that Western medicine uses mainly drugs for.