There are many reasons for thick, white foamy saliva, which may be caused by dry mucous membrane signs or by decreased estrogen production. 1. Mucosal desiccation: it is an autoimmune disease, the skin of the whole body, nasal mucosa and other relatively dry, oral mucosa congestion and edema, saliva is foamy, eye discomfort, symptoms of nasal cavity, knuckle pain. 2. Reduced estrogen secretion: common in some elderly women, after menopause, due to the reduction of estrogen, salivary gland fibrosis, salivary secretion is reduced, saliva viscous, inside the white foam increased. There are other possibilities for saliva sticky white foam, you should go to the hospital outpatient clinic in time, to clarify the cause of the disease, under the guidance of a professional physician, do not self-medication, so as not to delay the condition.